Lucas CAV DPA fuel pump leak

I have a leak of about 3 drops per second from my fuel pump. It is coming out the throttle linkage shaft. Has anyone ever worked on one of these and repaired the leak? The Fuel pump is a Lucas CAV DPA and is on a 1988 Cummins 6BT5.9M.
The picture is of the other engine without the leak. Of course the leak is on the injector pump that is outboard and hard to get to.

I have the same motor and CAV hpp. Almost the same year.

You might ask at your local Cummins shop if there is an easy fix without pulling the pump.

While my pump did not leak from your exact location, nor nearly as much fuel, I would get occasional drips from one of the delivery tube connections.

The right way to fix mine would be to remake the fitting and line - of course the leaky one was the furthest back to reach, and would require pulling at least 3 other ones out to get to it.

So, I just kept and eye on it and cleaned up the occasional bit of diesel. After 2 years, the drip went away.


Don't know if you will have the same luck, but you never know.

3 drops a second is normally called a steady flow

There are some good videos on utube showing the whole rebuild process of those Lucas pumps. Here is one link but there are several.
Lucas CAV Delphi diesel pump repair part 1 - YouTube

fryedaze said:

I have a leak of about 3 drops per second from my fuel pump. It is coming out the throttle linkage shaft.

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There are two O-rings on that shaft. Remove the cover and replace them.

Do the shutoff shaft O-rings while you are at it.

If you are not comfortable pulling the cover off, bend over.

Top cover gasket and O-rings complete

Well I finally finished the job. I had several recommendations to pull the whole pump so I could work work on it on the work bench. This was due to concerns of loosing part and ease of work, I didnt. Well..... I lost a very small spring 4 times and failed to recover it the last time. Luckily I was able to get one at a hardware store. The attache video is perfect for doing this type of pump. The big key is disconnect the main spring like he does in the video. Not on the other end like I did on the first attempt.

Top gasket reseal Cav- Injector Pump - YouTube

Hello My name is Martin Morales, I have purchased a 1979 34 ft mainship with a T6.354 perkins, after taken the boat out for the first time my wife noticed a diesel fuel smell. I didn't look at it right then since she was on vacation and this was the boats maiden voyage. Just before I left I did check the fuel leak and it was dripping from the throttle shaft of the injection pump.. So where can I purchased the O rings and gasket from?
I would be grateful.
Sincerely
Marty (sabaru350@gmail.com)

CAV Injection Pump Parts---2013

What injector pump do you have?

Well I now realize I wish I could tell you but the boat is in Brunswick GA, and I am in Colorado Springs. I figured wrong I assumed that all 1979 34 ft mainship with a T6.354 perkins were the same. I will have to get back to you in a month.
Sincerely
Martin Morales

I have (actually HAD) the exact same leak last month, but it wasn't the shaft or seal. The side cover had worn and cracked and needed replacing ($325 part). Moreover, the pump had to come out and get benched for the fix. You might want to be careful trying to self-diagnose those pumps. There's a lot going on. I never use a professional for things I feel like I can do myself, BUT this is one I will always call a pro for.

Tom.B said:

I have (actually HAD) the exact same leak last month, but it wasn't the shaft or seal. The side cover had worn and cracked and needed replacing ($325 part). Moreover, the pump had to come out and get benched for the fix. You might want to be careful trying to self-diagnose those pumps. There's a lot going on. I never use a professional for things I feel like I can do myself, BUT this is one I will always call a pro for.

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I agree with Tom for the most part. If it was anything more than pulling the top cover I would have a professional work on it.

Thank you all for the Info, I will let you guys know in a month, I have 2 weeks to work on the boat, what I will do I will Fed Ex the pump over night if it not coming from the throttle shaft.
Sincerely
Martin Morales

If YOU remove the pump just be sure to understand properly HOW to do so.

There is a timeing issue. Not knowlegeable about the Perkins but many engines have a specific procedure to set the crankshaft and maybe lock it so the timeing is held while the pump is removed and off.

Failure to attend to this can hugely complicate reinstallation. Just be sure you understand and follow the procedure.

I am reinstalling my CAV off my Perkins 6.354 this weekend. I had the exact same leak and I pulled the CAV and sent it to be totally rebuilt. Cost just over $600.

So far the only hiccup I have run into is I have to remake one of the supply lines from the fuel filter. I will check around town to see if I can get someone to put the flair I need in the end that attaches to the CAV unit. Those of you who have the perkins unit, do you know what that flair on the supply line is called or how to make it? Does the line have to extend beyond the flair like it does on the original?

From what I have read it doesn't seem to difficult, I have never remove one. I am a mechanic and have worked on 6.9 diesel and 7.3 power stroke. But experience is always a plus.
Thanks again for your info.

what year is your PERKINS, is it a Turbo?? I am in Colorado Springs and the boat is in Brunswick GA. Trying to at least by a kits to reseal the shaft with new O-Rings, I do not know the model number of the pump, I didn't look at it when I left for home.

To everyone who responded thank you, I am back in GA. I did find a diesel service shop, I feel at easy after talking to him Roy's diesel and injection service in Jacksonville FL. The pump was not to bad to remove, he had a lot of good tips on what not to do.

Looking for some spare fuel injectors, any help would be wonderful. It is a Delphi injector, IDES 5281610
Martin