bleeding a 2.5L diesel with Lucas CAV

[Lowlandbear]

I just installed a rebuilt Lucas CAV injector pump in my 2.5L diesel in my lightweight and I cannot seem to bleed the darn thing? I have bleed the filter and no air, then the injector pump on the top of the unit with the little bleed screw, and no air. When I bleed the injectors, all I get is foam and lots of it. I have spent my battery trying to bleed the air from the bloody thing. Am I missing something? (The guy who was helping me, a bonifide diesel mechanic, said he couldn't get the old injector pump to bleed either and recommended I get the rebuilt injector pump.)

It was a bear getting the timing on the marks and it defenately is not giving any suggestion it will start. I also noticed that the timing for the injector pump is right on the edge of the the pumps movement. I am tempted to change if off the marks my one tooth so it might have a little play.

Its been a couple of cold days working outside on the thing. I would really like to have it back on the road soon.

Thanks for any suggestions!

[leafsprung]

I have had a couple which refused to bleed completely after major work to the injection system. If all else is well, tow it around the block in gear. It should fire up and it will save your battery/starter.:thumb-up:

[Linus Tremaine]

I have a 2.5 diesel as well. when I got it I did some work to it and could not get it to bleed. I found after fighting it for a long time that it was plumbed incorrectly. It ran for some reason but the hoses were not going to the right places. I think it was actually the return line was plumbed into the feed line at the filter head so it was just returning to the tank rather than going to the pump.
Maybe not the same problem you are having but there is another post with a nice picture of the correct plumbing for a 2.5 with the pump and the filter head. Make sure yours is correct.

[SafeAirOne]

Occasionally these pumps can be OK to bleed. The other 93 Percent of the time they're a HUGE hassle.

The first time I ever ran it out of fuel, I couldn't for the life of me, get the thing bled/started. The guy at the local diesel pump shop told me to crack the fuel return line (on the front of the injector pump) open to let the entrapped air out, then close the line while somebody cranks the engine the whole time.

As soon as the fitting was re-tightened, the engine fired right up.

Unfortunately, that doesn't work all the time, especially with a completely dry (rebuilt) pump and empty injector lines. Sometimes you have to bleed the filter and pump several times (even though it looks air-free) and keep cracking the injector lines one-at-a-time till it starts up.

Since you have a freshly rebuilt unit, I doubt the following is the cause, but I understand that a faulty/leaking pump shaft seal can let air into the system causing similar problems.


Good luck!

[junkyddog11]

In my experience they are no different than any diesel pump as in they beeld easily if no one is around to see what a hero you are, but if the customer is watching they fight the whole time.
Inanimate object my arse !
Stick with it and you will win. I like Ike's towing in idea......trying to figure out how to do that solo.

[LaneRover]

In my experience they are no different than any diesel pump as in they beeld easily if no one is around to see what a hero you are, but if the customer is watching they fight the whole time.
Inanimate object my arse !
Stick with it and you will win. I like Ike's towing in idea......trying to figure out how to do that solo.

It is amazing how many inanimate objects really aren't!

Do you have a big hill nearby?

[SalemRover]

There is some play built into the mounting that allows a little fine tuning of the timing. Before you go and start fussing with the belt I would loose the 4 mounting bolts that hold the pump to the timing housing, the one bolt in the rear and the injector lines entering the pump. This will allow some rotation of the pump to adjust the timing.

I have never had to bleed a bone dry injection pump, but I do remember being bleary eyed at the winter romp a couple years ago trying to get my 2.5 to fire after a fuel gelling problem. We did try filling the injection pump with ATF manually. In the end it was bad fuel still present in the fuel filter that was causing it to not fire. Even after that my starter was so weak that it wasnt spinning the engine fast enough and we ended up towing it down the road to start it up.

Good Luck!

-Jason

[SafeAirOne]

Sometimes I wonder if it's a "volume" thing. As in "your engine will never start till there's 2 gallons of diesel on the ground under the engine". ;)

[Lowlandbear]

Ok, I have been working on this for several hours and it is still foaming our of the first bloody injector. I am wondering if the the thing is connected to the fuel lines properly.

Does the fuel connect the fuel filter to the back of the injector and the line from the front of the pump back to the filter connection #3?

I am hoping to have some time tomorrow during the day, since it is supposed to snow and rain, then rain all day fri.

Does anyone have a photo of how a working unit is connected? It may be that the diesel mechanic didn't put it back together exactly as it was.

Thank for all the good talk.

Peace,
James

[SafeAirOne]

I am wondering if the the thing is connected to the fuel lines properly.

Does the fuel connect the fuel filter to the back of the injector and the line from the front of the pump back to the filter connection #3?


See this thread (http://www.roversnorth.com/forums/showthread.php?t=11326)from a few days ago.

[fred98050]

Ok, I have been working on this for several hours and it is still foaming our of the first bloody injector. I am wondering if the the thing is connected to the fuel lines properly.

Does the fuel connect the fuel filter to the back of the injector and the line from the front of the pump back to the filter connection #3?

I am hoping to have some time tomorrow during the day, since it is supposed to snow and rain, then rain all day fri.

Does anyone have a photo of how a working unit is connected? It may be that the diesel mechanic didn't put it back together exactly as it was.

Thank for all the good talk.

Peace,
James

Hey James,

With the help of safeairone,

here is something that might help you concerning the plumbing:
http://www.roversnorth.com/forums/showthread.php?t=11326

Frederic

[SafeAirOne]

Finally...I've typed faster than somebody on this board!:D

[Lowlandbear]

Thank you for the Photo. It is setup correctly so it must be just getting all the air out. Time will tell later today.

Peace,
James

[SalemRover]

Sounds like you are drawing air into the system somehow, or the fuel pump has problems.

[SafeAirOne]

Out of curiosity, what prompted you to replace the original pump?