MB U1300L a good base to build on? [Archive]

boroburner

08-03-2010, 02:30 PM

Hello all! Im Ben Evers, from Canada EH! What a great forum you have here!

Ive been researching the RV lifestyle for about a yr and ahalf now and think its something id really enjoy/would suit my lifestyle. Ive been looking at Rv's for quite some time but came to the conclusion that they were more or less crap.... Then i discovered Expo Vehicles!! :Wow1: So here i am... still thinking of selling it all and running away(ok... driving really).

I have an option to buy a U1300L 20,000KM X-military rig from germany (I think it has the overdrive too!) and was wondering if it would be a suitable base for a full time expo rig? I know its possible(ive seen the pics!). Im wondering about the restrictions/problems i may plan to encounter with such a chasis/build.

Here are a few of my requirements
-serviceability and availability of parts(the more i look at this aspect the more i like the mog)

-sleeping area, kitchen and washroom facilitys including shower

-lots of electrical power!! I am a glass artist and would like to have a trailer to pull behind with a self supporting glass shop in it. This would require 120/240V power and 40 amps min. Ive been thinking a PTO gen for the mog may be able to do this??(any downside to this idea?) I would also like solar and maybe wind for the times im not working.

-Motorbike for getting around on 400CC

-The ability to pull a trailer(preferably with off road capabilitys as well) with aprox 3-4000lbs of glass and tools

-lots of storage, lots of fuel and lots of water would also be a big +

Im sure theres plenty of other things id love to bring/have but these are my bare essentials if i am to seriously consider this.
So... What do you think? Is the U1300L for me? Or should i look at something a little larger?

thanks in advance!
B

Chas Stricker

08-03-2010, 03:03 PM

Sounds like fun. I think the limiting factors for the 1300L would be size of camping space and the slow speed at which they like to travel. Towing is no problem, but, the speed does go down. Keep the weight down on the chassis. Good luck,
Chas

boroburner

08-03-2010, 03:33 PM

Thanks chas
Im thinking it could be very fun yes!! And im sure maddenig to the point to exaustion as well(im not going to think about that right now..) This project still in the research stage and I think it will be for some time to come too.

By limitation do you mean dimentions of living quarters? or weight?
Do you happen to know the aprox. weight/sf of the average well constructed expo camper(dry)?? Tortion free mount, well constructed steel subframe, lock boxes, bathroom, kitchen, a few windows, etc?

I dont feel like i need a tonne of room for myself. I am a man of few needs. But i do like creature comforts, like my own washroom:) And a full size bed would be great Im 6'6".

I love the idea of building my own rig but the idea of having to weigh everything to the gram(altho i would anyways) and fight with DOT to register it because i didnt buy a slightly lager vehicle sounds horrible. GVW is my biggest concern.

mhiscox

08-03-2010, 04:02 PM

Good luck with your project. There are certainly many U1300 campers, most commonly U1300Ls, the long wheelbase version for obvious reasons. The two biggest drawbacks of this truck for the purpose are the slow cruising speed (figure 55 mph for most variants) and the height and width of the truck when going on unimproved roads.

The maximum GVWR of a 1300L is 16,500 pounds, so weight should not be a problem unless you go crazy. Figure that 5,000 pounds should cover the cabin and the contents without resorting to esoteric materials in the construction. (Still, it's always worth making a list of all the weights and verifying all is well.)

BTW, there are good 1300 campers available for purchase at prices not far from what it would cost to build one yourself if you value your time for much. It's also worth just looking at the For Sale campers to see how they are done to give you ideas. Here are two examples for sale; there are others:

http://www.ki7xh.com/camper.htm

http://www.expedition-imports.com/category/vehicle_inventory.category_name.1_u1300l_expeditio n_camper/

Also, the cabin on my 416 camper is of similar size to what you'd put on a 1300, and there are lots of pictures with captions of it at:

http://picasaweb.google.com/mhiscox01/CamperMogAssortment#

Good luck,

Mike

boroburner

08-03-2010, 04:54 PM

Hi Mike! Thanks for the links!

Ive seen photos of your rig in my research already, a very nice unit! Im new to Mogs, and theyre kind of confusing... a 416 has a longer wheelbase than a 1300 does it not? room for the extended cab in your images?

Ive seen the build website for Bundeswehr in my research already as well. bookmarked it too! Its a resource im sure I will call upon. I have been toying with the idea of buying somone elses expo-mog(its almost looks cheaper) but i do really like the idea of building it myself. Im thinking.... if i build it, i can repair it. Ive recently gone thru a nightmare home reno in which improper and cost cutting measures were used by the original builder and would hate to inherit the same again. However.... Unlike my house, it does seem that most of these vehicles are put together with some sort of coherent thought process. So it is still very much a consideration.

Going fast isnt really a concern, Im not in a rush, getting there in one piece is of far more importance to me. In canada most roads have a speed limit of 90K anyways so aside from the trans canada, i think id be OK @ 55. Once outside of canada i hope Id be spending as much time on minor roads as possible. No point in having a mog if your not going to use it.... At least slightly.

Tennmogger

08-07-2010, 08:43 PM

Hi Ben, and welcome,

I'm a fan of the U-1300L with camper.

A PTO generator works fine, if you need that much power. I use a 10kW PTO generator (on another Unimog) for emergency use and it works fine, but, consider the fuel usage of a big engine like an OM-352 or OM-366 (both found in U-1300's) running at speed to get that generator on frequency. Plan on several gallons of fuel per hour, and that adds up. Also, a Diesel engine does not like to run with low load for many hours. A smaller generator, Diesel powered, rated at near the load you require, would be much more efficient and won't wear out your truck engine.

You might not find a U-1300 with a PTO, either. If the truck has an overdrive then it won't have a PTO.

Few military U-1300's have overdrive or fast axle ratios. However, many of the ex-fire service U-1300's do have fast ratios (like 5.3:1), and a Claas overdrive can be added (cost approaching $10k now, if you can find one). In addition, the fire service trucks often have a torsion isolating bed needed for a cabin build. Don't want that box twisting on the road.

Towing a reasonable load is certainly doable, but expect slower speeds. I pull an M-105A2 trailer with my U-1300 and know it's there, and I don't put "3-4000 lbs" in it.

The engines in these trucks are not overly powerful, just sufficient, and efficient. As the load goes up, the speed goes down, and gear shifting is needed.

Another point about the SBU series of Mogs: These were the last of the mechanically injected engines with no computers or electronics. To me, that's a huge selling point.

Bob

mhiscox

08-08-2010, 01:00 AM

A 416 has a longer wheelbase than a 1300 does it not? room for the extended cab in your images?
There are varying wheelbases on both 416s and 1300s, plus my 416 was built of a traction head (basically non-Mercedes from the end of the transmission back) so they could make any reasonable wheelbase they wanted. One big difference is whether the truck is a DoKa (double cab); basically you can have more cab or more cabin, by about 4 feet.

Going fast isnt really a concern, Im not in a rush, getting there in one piece is of far more importance to me. In canada most roads have a speed limit of 90K anyways so aside from the trans canada, i think id be OK @ 55.
The issue, as I suspect you understand, is not the extent to which power is related to top speed as much as it relates to grade handling. Camper Mog's somewhat tweaked 110 hp engine provided about the same cruise speed as many 170 hp 1300s, but when the grades came, Camper Mog was more affected. Don't misunderstand me; you always make it up the hills, but with the lower horsepower, you quite understandably make it up slower.

It's also worth noting that turbocharged engines will keep their power at altitude better than normally-aspirated ones. Figure about a 3% horsepower drop per 1000 feet above sea level.

Good luck.

Ford Prefect

08-09-2010, 07:17 AM

I know there is a guy over on benzworld.com (in the unimog forum) that is trying to sell a yellow 416 that is exactly like Mike's. To warn you, however, this guy's is a flying rust bucket, he will tell you that himself, so it would be a complete rebuild, but if you wanted a project...

If you are seriously interested in one of these things you REALLY need to find a way to get to the "North Western Mog Fest" on the 19th of this month. The reason is that they are not at all what you think they are, until you have ridden in one, and driven one. I have always wanted a mog, but spending time in one for a weekend convinced me that I am not going to pursue one until I retire, whereas I had planned to get one in the next two years. Glad that I spent time in them before buying and then realizing I did not want it yet!

Just a thought. There are a lot of other vehicles out there that can do the trips and carry the weight. Have you looked at the "Eco-Roamer" at all? Big build thread on here, but the guy is set up to sell you one if you would be interested. There are other vehicle platforms that are smaller, but a lot, than the mog and might also do you very nicely.

All I am saying is that you should explore your options. The Mog is only going to out do the 2wd overland vehicles on about five percent of the roads, and that really is not a lot. If you are thinking about going all out through Africa and staying off of the main roads while traveling through monsoon season, well then you will need a Mog or the like, otherwise there are a lot of other options out there.

Would love to see you build whatever you end up with though! Send photos... haha ;)

Brian

threepiece188

08-09-2010, 11:18 AM

charlieaarons

08-09-2010, 04:05 PM

In general, a Mog is much more reasonable for international travel than staying in N. America. Due to top speed limitations (even if you have an OD, you won't want to go over 95-100kph) and parts and service availability.
Vehicles built on medium duty "domestic" chassis fit N. american requirements well but become increasingly hard to find parts and service for as you get out of N. America, and then the W. Hemisphere altogether.
And do consider that a U1300, even if it has only 20000km, has been "sitting around" for years and will require work sometimes.

Charlie

mhiscox

08-09-2010, 04:42 PM

Can you please elaborate a bit as to why you don't want a Mog at this time? I too have been considering a Mog and also have not retired yet. I would like to know your thoughts on this.
Dan
Being a long-time Mog owner, and knowing dozens of people who have owned others, I propose that the crux of the matter in North America is the balance between transportation and hobby. Take a F550 from LA to NYC, and no one will think anything of it. Use a older Mog for that same trip, and you will be revered as an intrepid adventurer. There is an element of uncertainty with an older Mog that you do not have with a modern vehicle and you get a sense of accomplishment at making the trip. Any trip, for that matter, as taking the family to the McDonald's 15 miles down the road becomes an outing in a Mog.

I believe my view is particularly true for the gas-powered 404s, which were never designed for sustained high-speed running and the diesel 416s, most all of which are better than thirty-years old. There's a little more "transportation" in using one of the newer SBUs, though they're almost all better than twenty years old. (The "new" U500s are modern computer-controlled heavier trucks best considered a special case.)

Most Mogs are underpowered for their weight, noisy, cramped for many people and have no air conditioning. Does that mean you shouldn't want one? Of course not. People hike and get blisters, or ride in kayaks and get wet. Some inconvenience is an expected part of many hobbies. I have had many excellent adventures owning my Mog camper and would not have wanted to miss the experience. And for an expedition with a slower pace and the substantial load carrying across less-improved surfaces, they are tough to beat.

All in all, I never try to talk people out of owning an older Unimog, but I do try to make them think about whether their expectations are in line with how the trucks work in common North American situations.

Ford Prefect

08-10-2010, 02:39 PM

Can you please elaborate a bit as to why you don't want a Mog at this time? I too have been considering a Mog and also have not retired yet. I would like to know your thoughts on this.
Dan

I think that Charlie and Mike sum it up pretty well.

I love the 404, it is a great hobbiest vehicle, but you do not want to take it past the citly limits unless it is on a trailer behind a big Ford. I really like the 416, super fun truck, and it has some get up and go. It can make it down the road pretty well. I really love the SBU, and I dream about the U500, and the u141. Now, the 404 can be had for a relatively good price all things considered, the 416 will take a fairly serious bite out of your budget, and SBU costs as much as a brand new ML and therefore, obviously, ONE HECK of a hobby. The U500, well, you could have a fleet of ML's for that price. Some people are asking as high as $150,000.oo for those things. As for the 406, it has a shorter wheel base than my CJ7, and the U141, very cool, hard to find, hard to get parts, still around 30K for them.

In an ideal world, yes I would get one, but as it is, I need the money for my family.

Further I do not like to wrench on vehicles, which makes a mog significantly more expensive to maintain.

I think the biggest thing you need to know, outside of what Charlie and Mike mentioned, is that getting a Mog is a big deal. There is no way to really dabble in mogs IMHO. You either jump right in over your head, or not at all. It IS a hobby, not just a vehicle, you will be shocked if you think it is like going out and picking up a toyota, and expecting to drive it with nothing more than an oil change IF you happen to remember, every 4-5000 miles.

SO with luck, maybe in a couple decades I can get one. I'll be in my fifties. retired and have more time to do the wrenching and such.

OK, that was long-winded...

That being said, I think that the Mog is a perfect small vehicle base for an overlander. When you look at the campers on the backs of Mogs, you must be aware, that is a very small place to live for the next X period of time.

63tlf8

08-10-2010, 11:32 PM

I think that Charlie and Mike sum it up pretty well.

I love the 404, it is a great hobbiest vehicle, but you do not want to take it past the citly limits unless it is on a trailer behind a big Ford. I really like the 416, super fun truck, and it has some get up and go....... Now, the 404 can be had for a relatively good price all things considered, the 416 will take a fairly serious bite out of your budget, and SBU costs as much as a brand new ML and therefore, obviously, ONE HECK of a hobby. ........... There is no way to really dabble in mogs IMHO. You either jump right in over your head, or not at all. It IS a hobby, not just a vehicle, you will be shocked if you think it is like going out and picking up a toyota, and expecting to drive it with nothing more than an oil change IF you happen to remember, every 4-5000 miles.
......
That being said, I think that the Mog is a perfect small vehicle base for an overlander. When you look at the campers on the backs of Mogs, you must be aware, that is a very small place to live for the next X period of time.

What Mike and Charlie said plus the above is good advice for many / most, but it isn't cast in stone. My take is that the individual determines what is right for them with due consideration for their circumstances and intentions. I and some friends have 404 campers, one has owned his for 30 years. We happen to be older, used to working with the earlier style industrial type machinery and not obsessed with getting there yesterday. Also our chosen routes involve severe weight restrictions and a preference for a smaller footprint. One of these friends is currently away and will cover some 4 - 5,000 Km of essentially dirt or off-road in his 404 during this trip so it far so along with the worlds previous 404 adventures, it far exceeds the city limits scenario.

Living space depends on what you think is normal. One part of the world seems to exist very well in 3 - 3.5 Mtr cabins and is happy to be warm and dry and the other half need 4-5 Mtr cabs with hot and cold running water and dancing girls. A good 2 x 3 Mtr Expedition style cabin is sheer luxury after canvas and a 3 month trip is pretty well normal. I'd have a 1300 if weight wasn't an issue so I'm not a 404 or nothing man.

All that said, any older MOG is a lifestyle choice so if you are less than middle aged and challenged by spanners then it won't be a happy relationship. This forum tells you much. Some are here for many years as happy MOG owners and some pass through very quickly trailing a for sale sign acknowledging it wasn't for them.

So, if a MOG (model of your choice) is for you then you will be a happy owner, if its a status symbol or bling then it could be a very expensive experience. Only you can tell.

Cheers

Tony

charlieaarons

08-11-2010, 02:20 AM

. One part of the world seems to exist very well in 3 - 3.5 Mtr cabins and is happy to be warm and dry and the other half need 4-5 Mtr cabs with hot and cold running water and dancing girls.

I trust that's just a metaphor, my "dancing girl" is 56yo and I've been married to her for 30 yrs. She does require hot and cold running water and a flush toilet, thus the 4.8m camper. But at least she puts up with the Mog part. There's also room for a lot of spanners and spare parts and a Star Diagnostic computer.

Charlie

boroburner

09-25-2010, 07:30 PM

Thank you all for the advice so far.

The more im reserching Unimogs/expo campers the more im thinking i would like to get into one sometime in the future, distant or not is yet to be determined. The reason for the Unimog choice is that i am definetly interested in international travel and parts avalibility when travelling with this kind of rig seems to be a point that keeps comming up as i read peoples posts.
To date i have driven thru USA, Canada(many times), baja (3 times), crossed; ireland, UK, Germany, and am planning to visit Germany, France, Spain, and Italy this winter.... I regularly 4x4 to remote hotsprings in BC and would love to take my home and workshop with me on all these adventures.

Most of my travels have been in nothing bigger than a ford 1 tonne van and as small a vehicle as a volkswagan rabbit (germany :smiley_drive: )and im no stranger to a good ol tent and sleeping bag so anything would be a major step up, altho i do have to say i have a fondness for; dancing women, hot water and flush toilets...

Admitidly my mechanical skills would need a major overhaul, im not so good with vehicles, but i seem to be able to visualise and build most anything from scratch, ive got a good handle on 120/240 electrical, welding and machining but have never gotten down and dirty with a car or truck, ahhh time. I think tho with a book, a little help here and there from friends, this forum and a wrench i could figure out an older model. This is part of my desire to build my own form scratch.

As for space and power, for my glass shop to be self sufficent i would need to run; 1 kiln(20amps/240V), oxygen generator (5 amps/120V), and the killer... one rotary screw compressor (60 amps/240V). Major power requirements to be on the road with. For work space i do not need much, maybe 8'x8'. The compressor/oxy generator/kiln setup weighs in at a good ol 2000Lbs, then throw in another 700-1000 pounds of random tools, gas and stuff. This would be over and above a healthy stock of spare parts for the camper. I think i could cram the glass shop into a 18-20 foot trailer. Weight/power/GVRW is going to be my major concern i think.

Thanks again for all the input and advice. I hope this expalins a bit of who i am and my requirments.

Victorian

10-07-2010, 12:09 AM

Just found this one on youtube:
YouTube - Unimog 1300L camper for sale 1-250-229-4045

Not sure if its still available but certainly looks interesting!

ersatzknarf

10-07-2010, 12:14 AM

Wow ! That looks to be a very nice one and in clean condition, too...

Victorian

10-07-2010, 12:32 AM

Wow ! That looks to be a very nice one and in clean condition, too...

Looks like an ex military with new paint... who knows what it looks like underneath. But right now it certainly looks stellar!!! The phone number indicates that it must be located pretty close to Victoria,BC .

Incendo

10-12-2010, 07:19 PM

Looks like an ex military with new paint... who knows what it looks like underneath. But right now it certainly looks stellar!!! The phone number indicates that it must be located pretty close to Victoria,BC .

The Mog is located in Procter, BC which is north east of Nelson. I went to have a look at it earlier this summer and its in pretty good shape. The camper is fully detachable and would be good for some short trips. A bit more work would be needed on it to make it comfortable for longer journeys. However, all in all it seems to be in good shape.

mhiscox

10-13-2010, 04:47 PM

My Sprinter camper and I parked next to this truck at Northwest MogFest in August and I got a good tour of the unit and spent some time with the pleasant and knowledgeable owners. Whether you like it our not will have a lot to do with your travel and camping strategy. As noted, the sturdy shipping-container-like cabin will lift right out of the back of the bed, leaving you with a fully-functional cargo Mog. But this means that there is no pass-through from the cab to the cabin, which would be a significant drawback to some.

It's also the case that, in true expedition fashion, storage has been maximized, with drawers, bins, etc. everywhere. Great if you're on a very long trip, but if the truck is mostly going to be used for shorter trips, you might prefer a different layout.

On other thing for US potential owners . . . because of the ease with which the cabin comes out of the bed, I believe US Customs would almost certainly subject it to the 25% cargo truck duty, rather than the 2% duty on vehicles that are indisputably RVs. But I don't know whether, due to NAFTA or some such, the situation is different when importing from Canada. Worth checking on, given it's about a $9200 difference.

boroburner

10-14-2010, 02:43 PM

Thanks for the links to the mog! Shes a nice one i agree.

The more i think about this, the more i think i may want to build on something a little larger?? Perhaps a 2450/437(is that right?)? My ideal scenario is to "full time" in it. Ive looked at plenty of photos/CAD/specs and weighed a few things and im think I should look to a larger rig. There happens to be an RV dealer just outside of Frankfurt that has a selection of used expedition vehicles on their lot. Im planning to attend when i get to Germany and have a look at a few myself.
Woo hoooo!

Till then... lots of reserch!

Incendo

10-15-2010, 12:17 AM

If you're going over to Germany you may want to check this baby out. I was looking at it very seriously prior to buying the 1550L. From what I can recall, the vehicle, as a cab and chassis weighs around 6.000Kg and has a total allowable weight of 14.000 Kg. With the box on the back the vehicle has a payload of 6.500 - 7.000 kg. It may be big enough for what you need.

http://www.merex.de/e/gebrauchte/U2150L451993exWemhof.shtml

boroburner

10-16-2010, 06:01 PM

Wow!!
thanks for the link. Any idea what the asking price may be?

Can anyone tell me the contruction material(s) of a typical radio/ambulance box? Steel, i would guess?

Hilmar

10-16-2010, 07:04 PM

Forget it!
Their expected price (without taxes) is 35,000.00 Euro without any inspection or guarantee.
It's a prototype with a wheelbase of 4.3m - no spare parts available for the long wheelbase.
The gearbox was shifted further to the back than in a series-produced model.

Hilmar

boroburner

10-16-2010, 07:55 PM

Thank you very much for the info! I will be sure to steer clear

boroburner

10-16-2010, 07:58 PM

is this true of all 2150L's? Or just this particular one?

Iain_U1250

10-17-2010, 09:32 AM

Forget it!
Their expected price (without taxes) is 35,000.00 Euro without any inspection or guarantee.
It's a prototype with a wheelbase of 3.80 m - no spare parts available for the long wheelbase.
The gearbox was shifted further to the back than in a series-produced model.

Hilmar

That one has a 4.3m wheelbase - it is different from normal 3.8m wheelbase U2150 which are standard and part of the normal Unimog range

Hilmar

10-17-2010, 10:52 AM

just this particular one!

Hilmar

10-17-2010, 10:55 AM

That one has a 4.3m wheelbase

Iain, you are right!

charlieaarons

10-17-2010, 08:52 PM

Iain, you are right!
4500 mm wheelbase I believe. With CTIS
and 8000-8500 kg rear axle capacity it seems ideal
for a campervan if OK on rust and mechanicals.

Charlie

boroburner

10-18-2010, 03:34 PM

Incendo

10-18-2010, 04:59 PM

what would be the hard parts to source? I guess the driveshaft legnth would be different due to the longer wheelbase? (again, i know very little about "mechanicals"... so far).

I have to say CTIS is appealing indeed. Does anyone know the cost to add it aftermarket?

The 1550 I recently purchased does not have CTIS on it. I inquired what the cost would be to install a system and was quoted two different options:

2,400 Euro
Four boxes with spiral hoses and quick couplers to the tire valves and one pressure regulation box.

12,000 Euro
Install of full system - would require new axles.

Although it would be a nice option to have, the additional cost didn't fit within my budget. So, if you can get one already installed, I think that would be a nice bonus.

In terms of the 2150, I was quoted a price of 3,500 Euro for a technical inspection, service and oil change. This included the removal of all wheels, checking of brakes, replacing of callipers if needed, etc. This cost would include the replacement of any non-functioning or warn parts affecting the technical function of the vehicle. Once the technical inspection was done, the company would be prepared to offer me a 3-month guarantee on the drive-train (engine, transmission, axles, etc.). If anything went wrong, replacement parts would be shipped to the destination of my choice, free of charge.

I believe the 35,000 Euro asking price is the same whether or not you take the box on the back or not. Additional details I received on this vehicle are as follows:

A30 Central tyre inflation system (CTIS)
B42 Dual line trailer brakes
B68 Trailer brake connections front
C26 Stabilizer, front axle
C29 Stabilizer, rear axle
C67 Fuel tank, 230Ltr.
F60 Hydr. tilting device for cabin
J32 Tachometer
L20 Reversing light
L25 Rear fog light
L30 Headlight protection
Performance 214 HP
P99 Cargo bed, LxB 4.500 x 2.400mm
Box body, de-mountable, LxBxH 4.800 x 2.400 x 1.600/2.000 mm rear doors and door rhs
Werner Front recovery winch
Aufbau / Implements
L41 Additional blinkers
L47 Front driving lights
M65 Vertical air intake
N16 Hi-speed PTO drive
P99 Cargo bed
Q** NATO-type trailer coupling
S12 Twin passenger seat
S21 Safety belts
S82 Wide angle mirror
S83 Ramp mirror
X19 GVW 14.000 Kg

Aside from the stated concerns regarding the extended lenght, it seems to be quite a good match for what you are looking for.

Iain_U1250

10-20-2010, 10:41 AM

I know of a guy who sells a CTIS system retrofit for a lot less than $12K - it requires a bit of machining of the portals, but it all seems doable. I was thinking of fitting one to my truck, but I'm developing my own quick connect system which should be a lot cheaper and simpler.

It's still in the development stage, but I've got most of the concept worked out. It is digitally controlled through commercially available instruments - just set the pressure on the control for front or rear axle, open up the valves for inflation or deflation, connect the hoses to the tyres and the solenoids do the rest. It should cost less than $1000 all up and runs off the on board air system. On my truck I'll have two compressors capable of putting out around 15cfm in total and 50lt of 8 Bar air in the air tanks, so inflation should be quick enough.

I'll post up the details once I have it all working.

LukeH

10-22-2010, 11:41 AM

boroburner

10-23-2010, 02:27 PM

Wowezers!!!! 12K! Could buy another mog for that almost.

I carry a compressor in the back all the time in my FJ and its a pain in the a** to stop and change pressure with any kind of regularity. And thats with stock 32"s. If changing terrain a few times in a day i spend a great deal of time on the side of the road already. I would dread to fill the monsters that are on the average mog. Even with a huge tank/compressor, i can imagine it would take some time to fill, not to mention setup/cleanup? CTIS seems to be fairly common on alot of the european used models, if i do get a Mog i think i will lean toward looking for one with it already equipt.

Luke, your explanation was exactly what i was looking for. Thank you. I wouldnt even catagorize myself in the class of novice mechanic yet, i have never fixed so much as a lawn mower. I can change my own oil/flats and have swapped a fuel pump in a 82 tracker. This is my mechanical exp....
Limited i know. Ive never had anything else to fix?

dan johnson

10-25-2010, 06:57 AM

I have had two mog with CTIS a U500 and a 1550 that I still own. When they work they are great but it adds another level of complexity to the system. The system on both mogs are divide between the front and rear. When you lower the rear tires you do both of them at the same time. The same with the front. On the U500 I did not drive it much in the winter and in the spring both rear tires were flat and off the beads. It takes a little while to jack up both tires and get out the air cannon to get them back on the beads. The other option is to take off the tires and haul them to a repair shop but at a couple of hundred lbs per tire the first way is easier. If you have a flat tire on one side the other side will also go flat. So now you have two flat tires. To stop the good tire from going flat you have to take off 3 lug nuts to disconnect the CTIS for that tire.

The 1550 has the same system as the U500 but does not have the computer to tell you the tires are low and it will blow them up if they are below the accepted level when you go over 40 mph. The one advantage of the 1550 is that you can disconnect the CTIS by only removing two 17mm bolts that hold the protection cover on. I kept a 17mm ratchet in the door pocket for those occasions.

One time while going across the Altar Desert in Mexico I was going down over a sand dune and got more sideways than I should have and both the downhill tires came off the beads. I was running between 10-12 psi in the tires. It is sort of a sinking feeling when you realize you have 3 tires to rebead and one to re-inflate. I was able to disconnect one of the uphill tires before it debeaded but not fast enough to do both. I was with a few other mogger and it only took about an hour or so to get going but we were all very experienced at doing this.

When I first got my 1550 I was told that the CTIS system had just been rebuilt. I replaced all the seals in the system since then once. I think that sand in the tires does not help the system much. I also do not think it is a good idea to use those beads they put in tires to help balance tires. At the present time the 1550 does not have the CTIS system hooked up. But I know when I want to use the mog that there is a good chance the tires will be up.

The system is nice when working but I would not pay any extra for it. It does not make the mog any more reliable.

Dan

Iain_U1250

10-25-2010, 08:09 AM

Based on your experience I think that the standard CTIS system is a bit lacking in the engineering department. I would have thought that if you get a puncture, then the air system would try it's best to keep the keep that tyre up to pressure - and you would notice the overall system air pressure dropping (or at least one circuit) that would give you an indication that you were losing air. If all it does is to manually allow you to adjust the pressures, then it seems to me to be hardly worth the effort. The after market kit I was looking at would certainly be trying to continuously re-inflate the tyre with a puncture.

Regarding your debeading problem - I have Staun beadlocks in my wheels - I have not used the Mog as yet, but I know experience with smaller tyres (33") I can drop the tyres down to to "0" PSI and they won't de-bead. The Staun guys assured me this would still be the case with the Mog tyres as I would have 50 psi or so holding the bead onto the rim even if the tyres themselves were completely deflated.

LukeH

10-25-2010, 10:33 AM

It's quite clear that a rotating seal isn't going to be as airtight as a fixed tyre valve.
Somewhere down the line there's a transition from fixed supply pipe to rotating part to feed to the wheel, that's always going to be a compromise.
You could make the seal pressure higher to keep the air in better, but then you'd have friction, lubrication and wear issues at that point forcing higher maintenance.
CTIS is going to make you less hesitant to air down which is a good thing for getting past obstacles, until you break the beads (which isn't the CTIS's fault after all)

I've watched the Truck trial Tatras start their day with six completely flat tyres. They just fire up the engine and wait, eventually they're aired up and off they go.

So it appears that some form of beadlock is a good idea, in any case.
One could also install a stop valve on each wheel where the CTIS connects to the tyre valve, just to be sure there's air in the tyres the next morning.

Personally I'd use the CTIS for levelling the truck in the evening, although it might get a bit wobbly if you let it down too much...

boroburner

10-25-2010, 02:19 PM

Would you say overall youve save time with the CTIS system? Given extra; maintenance, 2nd tire rebeading, etc. As apposed to havig to stop and manually air up/down?

I too find it suprising that there isn't a valve of some sort on the system to prevent both tyres from deflating, if there is a problem? Esp. on the new computer controlled models. Surely there must exist something(similar to a "bradly check valve" to prevent syphoning) that could counter this??

Could it be for safety that the system would be designed like this? Maybe having 2 tyres deflated/ing provides better control when carrying heavy loads at speed?

charlieaarons

10-25-2010, 07:28 PM

In the U500 it does automatically inflate when
a given pressure/speed ratio is out of range, unless
the override switch is on. After 4.5 years I only leak
1%/day out of the front, no change since new.

Charlie

boroburner

10-26-2010, 12:30 PM

does the U500 system isolate the tire, or do you stll have the issue of both sides deflating?

dan johnson

10-31-2010, 07:25 AM

[QUOTE=boroburner;737789]Would you say overall youve save time with the CTIS system? Given extra; maintenance, 2nd tire rebeading, etc. As apposed to havig to stop and manually air up/down?

It all depends what you are doing. If you are going from asphalt to soft terrain a number of times per day it could be very helpful. If you use your mog on a regular basis on and off road it can be very handy. I my case the mogs sit for a long time between use so they bleed down as time goes by.

The system is nice in that every time you get in the mog you know exactly what your tire pressure is. If it is not right you can adjust it as you are going down the road. That will probably make your tires last longer. It is also interesting to watch the tire pressure increase as the tire temperature goes up.

On the u500 if the tire pressure get below a specific psi when you are going over a certain speed a buzzer goes off. On the 1550 if you do not catch the pressure gauge going down both tires can go flat. On one occasion I noticed the pressure dropping so I switched on the inflate switch and we we able to get to the camp we were going to before we had to stop and fix the problem.

The 1550 has a high output water cooled air compressor the runs off a belt. The system maintains an 18 bar pressure (260 psi).

If you have CTIS use it but if you find a nice vehicle without it I would not pass it up. Most people do not have it and do fine.

Dan

grizzlyj

10-31-2010, 12:17 PM

My split rims currently deflate too quickly from either leaky beads or valves (new valves are in the post)

So whenever we move it can take an hour of inflation using the little Merc inflation tube to get the two or three that need attention to running psi. Not a normal situation, but remounting them, or getting back to highway pressure takes ages with this hose set up.

Maybe CTIS is overkill, but the four spiral hoses from one control box seems a big improvement over what I have now if the air flows more freely.

IMHO a decent sized box on a 1300 filled with long term stuff will probably put your weight too high for the chassis. Aim for a moderate box, or a severely light build and you should be fine :)