Onan Kiki Fuel Leak

[waterman46]

My Onan MDJE uses a Kiki injection pump. After I tightened the high pressure line to fix a small leak there, I got that leak stopped but now there is a small leak which I'm fairly sure is between the distribution valve and the pump body.

Have not been able to determine what components form that seal but I assume from other research that there is a copper gasket and possibly a rubber O-ring as well.

Cummins/Onan were absolutely no help - the numbers on the pump didn't correspond to anything they could look up. The generator nameplate is long gone but I do have the serial number. In any event it seems there are no new replacements available for the whole pump or any part of it.

The gen runs really great, only has 1400 hours on it and I can't see scrapping it so I'm looking for some way to fix this seal. I'm in Mexico at this time and headed home in two days. I'm thinking of removing the injection pump and taking it back to the US to put into the hands of an injection pump shop that I've had good results with in the past. Is this a good approach or should I try to remove just the leaky distribution valve and try to find or manufacture a new copper gasket (if that is the problem).

Removing the pump brings up other issues because then I need a new gasket to the block and the timing will need to be re-set using depth gauge and shims. I have not been able to find a source of replacements for either shims or the gasket.

In case I'm missing some idea here, does anyone have a useful suggestion other than replacing the whole darn genset because of a slow fuel leak?
Any sources for parts, new or used? Specialty injection pump rebuild companies?

Doug
Currently in Puerto Vallarta

[Diesel Bill]

Hi Doug, Pretty sure the delivery valves are seated on a copper washer. You can loosen the fuel line nut and then try to take up a little bit on the delivery valve then tighten up on the fuel line nut again. Iv'e seen these copper washers work harden so that no matter how tight you go the leak won't stop. If that's the case all you can do is replace the washer.
I sent you a private message to e-mail me and I can send you the shop manual for this gen set on PDF. If you can't find a replacement washer you can pull the old one and heat it with a flame to anneal it. Sometimes that will work till you find a replacement.
I did that with a copper head gasket from a D-6 Caterpillar engine.
Good luck, Diesel Bill

[GordMay]

Interesting tutorial on the Kiki Pump ➥ https://www.smokstak.com/forum/showthread.php?t=129194

Onan Service Manual ➥ https://cdn.greenmountaingenerators....S-974-0750.pdf

From a Nissan Manual ➥ http://www.4x4.ee/docs/nissan-SD-die...es/sd-3of3.pdf

[Lepke]

Most injector pump rebuilders can repair any pump. Copper washers, o-rings, etc., could also be bought there.

[waterman46]

To those who responed, thanks for your advice. I do already have the service manuals for the generator and the engine part of the Onan.

Today I did remove the leaky distribution valve and it turns out the copper washer is actually cracked. Now, I need to figure out how to remove it. Just attacking it with one or two pairs of tweezers did nothing but scratch its surface (not a problem, it must be replaced). I suppose it might fall out if I remove the injection pump and turn it upside down, but I hesitate to do that if there is some other way to remove the washer. Anyone have any ideas on that? The copper washer is located rather deep inside an annular cavity formed by a male thread inside the washer and a female thread outside the washer (the female thread in the pump body that holds the valve itself).

Doug

[Diesel Bill]

Originally Posted by waterman46

To those who responed, thanks for your advice. I do already have the service manuals for the generator and the engine part of the Onan.

Today I did remove the leaky distribution valve and it turns out the copper washer is actually cracked. Now, I need to figure out how to remove it. Just attacking it with one or two pairs of tweezers did nothing but scratch its surface (not a problem, it must be replaced). I suppose it might fall out if I remove the injection pump and turn it upside down, but I hesitate to do that if there is some other way to remove the washer. Anyone have any ideas on that? The copper washer is located rather deep inside an annular cavity formed by a male thread inside the washer and a female thread outside the washer (the female thread in the pump body that holds the valve itself).

Doug

Dental picks work well for this job. Lacking these cut a wire coat hanger to a working length and peen the end with a hammer to a small spoon shape and bend the end to slip under the washer.

[Wotname]

Originally Posted by Diesel Bill

....... Iv'e seen these copper washers work harden so that no matter how tight you go the leak won't stop. If that's the case all you can do is replace the washer.
......

FWIW, most copper washers that have been work hardened can be annealed quite simply by heating to a dull red and allowing to cool. This can be achieved using a gas flame on the stove etc.

I do note this will not help the OP as he states the copper washer has crackled.

[Diesel Bill]

Originally Posted by Wotname

FWIW, most copper washers that have been work hardened can be annealed quite simply by heating to a dull red and allowing to cool. This can be achieved using a gas flame on the stove etc.

I do note this will not help the OP as he states the copper washer has crackled.

I mentioned annealing with flame in my first post at the bottom.
You only did a partial quote and left that part out. Why?
Thanks, Diesel Bill

[Wotname]

Originally Posted by Diesel Bill

I mentioned annealing with flame in my first post at the bottom.
You only did a partial quote and left that part out. Why?
Thanks, Diesel Bill

Diesel Bill, please accept my apology for not reading your previous post correctly. Yes you did mention annealing at the end of your post and I missed it - my bad.

Somehow I must have stopped reading or at least stopped comprehending after your earlier definitive statement about getting new washers.

[Diesel Bill]

Hi Wotname, No problem. We are both only trying to help. Some times my writing goes in a round about way and I add things that could have been put in a clearer fashion.
My sister was an English major and I can't put 2 sentences together in the right order.

Peace, Diesel Bill