Lucas CAV pump help

Ultradog MN said:

Here is a write-up I made on another board.

"I don't claim to be a pump man but my guess is the problem is your metering valve.
On those CAV pumps it is rather common for them to get stuck in the off position.
Here is a post with a picture I put up on another forum that explains how to free it up.
It has helped many guys get their tractor started.
"First of all CLEAN your pump and its surroundings.
Pressure wash it then use brake cleaner.
You do NOT want any dirt inside.
Shut fuel off at the tank.
Remove the throttle rod and shut off cable.
Cut the wire that has the lead seal on it.
Remove the two nuts that hold the top cover on the pump. There are washers under the nuts. Do not lose them or your cover will leak.
Carefully lift the cover of the pump about 3/4".
Do NOT overstretch or remove the spring that is attached under the cover.
The photo below shows the pump backwards from what you will actually see. Note the slide bar #3. That will be right in front of you when you lift the cover. That slide bar operates the metering valve. See the red arrow. Metering valve has a very weak spring that should return it forward to run position. They get stuck in the off position. Free it up with a small screwdriver or popsicle stick - move it back and forth till it returns forward on it's own.
Get the slide bar located properly - that can be tricky so use due care. Replace the cover. Replace the washers and nuts.
Some say you will ruin the gasket under the cover when you do this. I have done this a half dozen times and gasket was always fine.
Turn on the fuel and bleed the filter/s. Bleed the pump. Crack all 3 injector lines at the injectors, turn the engine with the starter and bleed them all simultaneously. Then retighten the injector lines . It should start then.
Remember this pic is backwards.
It really is Very simple to do so don't be scared of it.
Let us know how it goes."

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Dieseltech said:

That won't work if the rotor plungers are stuck, and you are extremely LUCKY reusing the top cover gasket.

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jrsavoie said:

I have the same no start issue.

I also know I have a small leak someplace.
We couldn't feel anything on or around the Cav pump.

I overnight there will be about a 3" circle on a piece of cardboard on the floor. The spot will be a few inches in front of the cav pump. Not directly below it.

It possible it could be hydraulic fluid. But I think it smelled like diesel.

Would it drop there if the thermal start was leaking?

We haven't found where the leak is coming from. Or even Identified the fluid for positive sure. I can't smell hardly anything. It's a plus sometimes. Other times, like when we had a gas leak in the basement, it was a good thing I had people down there.

I have a GM AC Delco EP158 lift pump, 8-9 psi. I was thinking about installing between the petcock and the filter.

I was cautioned against installing the lift pump because it could possibly damage the Cav pump.

Do you have an opinion on this?

Is there risk at 8-9 psi?

Is there risk if I install the pump, but don't attempt to start the machine?

Thank you

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Dieseltech said:

Electric supply pumps are OK, 3-5 PSI is enough. 8-9 PSI is higher than needed, but won't hurt anything.

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jrsavoie said:

Thank you
The GM pump is what I have around for the old GMT400 6.5 diesels.
I was surprised it had about the same specs as the lift pump on my Toro 223D Groundsmaster with 23 HP Mitsubishi L3E. I used one there too, rather than wait for a Toro pump to arrive

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