Priming Diesel after filter change in an OM366LA

giantiger

New member
when there's air seeps inside the fuel pump or injector hoses, if you tighten the fuel filter cap, it makes pressure onto the cap, pushes the cap, that's why the filter cap couldn't be sit onto the housing thoroughly. After the air bled out of the housing, it is so easy to tighten the filter cap! It seems the Racor button on the hand pump of the water/fuel separator is useless, since we didn't feel pressure on it after 100 times push.
 

Joe917

Explorer
Glad to hear you got it going but...
Not sure what the issue was. What happens next time you change the filter? Spraying engine starter is not the normal post filter change procedure, what will you do differently. Any time you change the filter you will get air in the system.
 

loonwheeler

Adventurer
We have a Racor system and the manual pump button definitely works to prime the filter. Maybe yours is broken somehow? My procedure is to prime the water separator first then use the other manual pump to prime the fuel filters and IP. Has worked flawlessly for me several times.
 

Wyuna

Observer
If the Racor isn't working as it should, it might be easier to replace it now than having this issue out in the field.
 

thebigblue

Adventurer
Glad to hear you got it going but...
Not sure what the issue was. What happens next time you change the filter? Spraying engine starter is not the normal post filter change procedure, what will you do differently. Any time you change the filter you will get air in the system.
Yes, as i stated earlier, starting an engine spaying diesel starter should be avoided, it´s bad for the engine... especially connection rods and crankshaft can be damaged.
 
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grizzlyj

Adventurer
Hi
Glad you got it going.
As well as filling the filter housing with fuel, you can also leave the new filter itself soaking in diesel. Previously I had one paper filter and one felt but both benefited from a soak to get the air bubbles out before fitting. Probably not necessary but might help at times.
Maybe you won't feel any pressure on the hand pump until it pushes on fuel not air?
:)
 

giantiger

New member
that night after fuel filter got changed, I forgot to start engine to run for a few minutes but just went to bed. the next morning engine can't being started then I realized that the engine got air inside need priming. for next filter change,
what I would do is, take out the filter element and receptacle, then turn the key to ignition and hold for 20 seconds, let the engine cranking, repeat a few times, till no air bubble come through the diesel at the bottom of the filter housing, then put the receptacle and filter back, tighten the cap, start engine. will never forget to start engine......
Since so hard to get parts, I will prepare some spare parts now for the future on road.
 

giantiger

New member
Hi
Glad you got it going.
As well as filling the filter housing with fuel, you can also leave the new filter itself soaking in diesel. Previously I had one paper filter and one felt but both benefited from a soak to get the air bubbles out before fitting. Probably not necessary but might help at times.
Maybe you won't feel any pressure on the hand pump until it pushes on fuel not air?
:)
I agree. coz each time I open the fuel filter cap, the diesel is almost full inside housing...obviously the Racor did the job well.
 

giantiger

New member
We have a Racor system and the manual pump button definitely works to prime the filter. Maybe yours is broken somehow? My procedure is to prime the water separator first then use the other manual pump to prime the fuel filters and IP. Has worked flawlessly for me several times.
I don't see other hand pump than the Racor on the water/fuel separator element. maybe mine Mog got no hand pump?
 

giantiger

New member
Glad to hear you got it going but...
Not sure what the issue was. What happens next time you change the filter? Spraying engine starter is not the normal post filter change procedure, what will you do differently. Any time you change the filter you will get air in the system.
I could only assume, the start problem caused by my neglect of forgot to start the engine soon after the fuel filter change, and I didn't prime engine soon after the filter change. I found it couldn't get started the next morning. Possibly the dry, new filter absorbed some fuel inside it, and if the engine start in time, it would be ok. Unfortunately I forgot to start engine. I will not allow that embarrassed thing happen again.... because I learned now..
 

thebigblue

Adventurer
Maybe fit a electrical pump before the filter, I did this on a 1986 VW LT 2.4 D diesel that had a hard time starting after not driving for 2 weeks, inexpensive fix. Found a membrane pump that would give 1,5 times the max. engine fuel flow. The pump is hooked to the solenoid and therefor runs when ignition is on, and also the returnline line to the tank is open, I will let it run for 5 to 10 sec. before attempting a start. Something like this might help your engine next time.
 

Spanna 53

Member
Over the years have had many fuel bleeding issues Vito vans we primed the filters with injector cleaner fluid , Land Cruisers have the pump on the top of the filter had to replace one with a CAV one for half the price of a Toyota one have jacked up the rear end of a Madza T4000 so the fuel level was above the filter , pressurised the tank to recharge the lines , there is on the market now a squeeze pump simalar to one on a boat portable fuel tank ,customers would often have vehicles towed in after trying do filter changes when they had seen it done on YouTube and it looked easy . At times even in a well equiped workshop it can be problematic always at the most inconvenient time ie 4.30 Friday afternoon so good luck next time
 
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