Cav pump leaking question...

[PeteTheRookie]

Geez, btw diesel and hydro seems every time I manage to get one leak stopped another springs up some where else.

What is under the cap nut on the left?
it is leaking a slow but steady drip from under that cap nut now while running.
Also noticed a wee bit of seepage from the edge of the nut on the right.

Tks

Pete
 

[PeteTheRookie]

pic uploaded but did not get in post?

 

[Bern]

You can try to tighten said fittings that are leaking. If the leak does not stop, replace the seal washers that reside on both sides of the fitting.
 

[Pops1532]

Should be an easy fix. Replace the copper washers.
 

[PeteTheRookie]

Tks guys.
Ok, so the one on the right is copper washers.

I did already try snug both these up and that did nothing on the pipe fitting and may have made the one on the left, what I have been called a cap nut, a little worse.

My questions is CAN I TAKE off the cap nut?
Is there anything like a spring or whatever that I
should watch out for or not touch at all.

Thing is I am in the middle of digging foundation for garage and can not afford to have TLB down right now.

TLB seems a little under powered. If it is not getting full fuel pressure or sucking air that would explain the slight lack of power.

Pete
 

[PeteTheRookie]

Ok,
So I loosened the leaking cap nut on the left while the motor was running. Diesel pulsed out, tightened it and it did stop leaking.
Also got down underneath and using 2 open end wrenches with pipes over the handles tightened the main hydro supply line connector that was leaking.
Yes another one stopped dripping.

Pete
 

[Greg Wolodkin]

Hi Pete -
The one you've marked on the right is the banjo fitting on the input side of the pump. It's a hollow bolt, with one copper washer on either side of the banjo itself.

The one on the left is one of the banjo fittings on the output side of the pump, so loosening that would push high pressure diesel out while the pump is running. Be careful with the high pressure side of things, especially with diesel.

I've only worked on the input side of my pump's fuel lines, so look for better advice from someone who has done the injector side before. But check the parts diagrams at Messicks and look for the washers (part #37 on the larger right-hand fitting, part #53 on the smaller left hand fitting, two washers per banjo) they are cheap and likely available locally from e.g. NAPA. With the engine and fuel shut off, you can R&R these connections with new washers but you'll have to bleed the fuel system after that to get the air out. Might not want to start a project like that until you finish the foundation though. Bleeding the system isn't too hard but I found it stressful the first time I did it as it seemed to take more cranking than I thought it would. Better to probably get all of the leaks (tank valve, etc.) all done once and bleed once. Put new fuel filters in place while you're at it and take time to R&R the fuel filter head and gaskets as well, or just replace it if it's in bad shape. Those parts are also readily available and not too much money.

In the meantime, your loosen and re-snug sounds like it may have helped enough to get you through the current project.

Hope this helps -
Greg
 

[Bern]

Yes, you can take off the "cap nut" as you call it, without any issues.

This fitting uses washers that are not copper. Not sure what they are made out of, but copper will not seal against those high pressures. Go to the dealer and get what's called for.
 

[Greg Wolodkin]

[Pops1532]

[Brian Allen]

Hi Pete
Unless your leak is running a lot of fuel on the ground, I would leave it.
What looks like a lot, may only be a tablespoon full hourly!
I believe you would be better off, if you let it leak until you have time to work on it.
Sometimes these projects have a way of mushrooming!
Good luck with whatever you decide!
Brian