Injection Pump Leaks, Please advise

[Rodger]

Hello All

My multifuel M109's injection pump is leaking fuel. It appears to be coming from under the plate with an arrow showing the direction fuel enters the high pressure lines to the injectors. (on some IP's this has been painted over. It is right under where the six high pressure lines leave the pump and go to the injectors.)
The plate is riveted on. Also, it started right up last week, now it needs a shot of ether to start.

I have looked in the TM's and found how to remove the IP and how to inspect it before installing, nothing about leaks.

questions:
1. Can I remove the 2 rivets and plate with the arrow to see what is behind it, with no risk of damaging anything?
2. What is behind the plate with the arrow.
3. Is this repairable, or do I need to change the IP?
4. what else do I need to know?

Thank you
Rodger

 

[gimpyrobb]

That plate has nothing under it. Check and make sure the center plug is snug. Post some pics so we know what you are talking about. It could just be O-rings,

 

[Rodger]

The leak appears to be from under the plate that the pencil is pointing at.
The fuel is hard to see and harder to photograph.

The center plug or bolt is tight.

 

[SCSG-G4]

Isn't that the HH data plate?

 

[Rodger]

What does HH stand for?

I am going to put UV dye in the fuel filter and see if I can find the leak tonight.

thank you
Rodger

 

[phil2968]

Hydraulic Head.

 

[hoop]

The leak is coming from the Screw on the right side of the plate. It probably cracked between the hole in the side and the end or the threads....it is really hard to see. Back off your fuel some.

 

[3dAngus]

This is a picture or two, of a new hydraulic head. Maybe it might help a bit.

 

[Rodger]

Infrared dye shows it is coming from under the data plate on the HH. I could not get a real good look but the two screws look like rivets.

I read the procedure to turn up the fuel to learn how to turn it down. I do not understand it. I will read more.

Hoop, how does turning the fuel down reduce leakage?

thank you all
Rodger

 

[hoop]

I do not fully understand all the insides of the HH, but I do know if the fuel is turned up too much, it will crack that screw on the side of the head.
But your leak is under the plate, so my idea will not help.

 

[Rodger]

I is on the left side. It might be a cracked screw or rivet on that side, with the plate diverting the leak.

Can the rivets be ground off to remove the plate?
Or the screws be removed to remove the plate.?

Thank you
Rodger

 

[gimpyrobb]

I have not heard of anyone else having this issue. I think you are in un-charted waters here. If you are leaking fuel from under that plate, be prepared to find a new HH. I say go ahead and remove the rivets to see what you are dealing with. Please post pics of what you find.

Also, Hoop was talking about the 12 point bolt next to your plate. Those have a history of cracking on us. Mine is one that cracked. I was lucky enough that I found one to replace my broken one, but it took 5 different tries to find it.

 

[VPed]

I am very far from having any experience with what you guys are discussing but I do think there is a posibility the data plate is not retained by true rivets. I have seen alot of data plates attached to may things automotive and generally, rivets are for when the plate is attached to sheetmetal. For castings and such with thickness to them, those things that look like rivets are usually like little nails with spiral flutes on the shank. Before grinding, you may want to grab the head with vise-grips and twist counterclockwise while pulling out. they may just "unscrew".

Vick

 

[kennys@wi.rr.com]

I have seen this leak before. It's either the top "plug" or an injector line. It will run down the side and appear to be comming from there. Another deuce owner brought his truck to my shop with the same leak. He too used the UV dye. I just hosed the engine off real good and reved the motor while looking for the leak. So far the only places I have seen that leak are thetop plug, side plug and loose injector line. For some reason the fan deposites fuel right there making you think that's where the leak is. Best of luck.

 

[deathrowdave]

Those are what are known as drive rivets , drill the correct size hole are drive them in !!!! As for the leak I am betting it is a fuel line leak , I looked for days to find one . Could not stop it by tightening , I had to replace the HH . In stall new Orings while the head is off also .

 

[kennys@wi.rr.com]

Might be time for another group buy of heads.

 

[Rodger]

Hello all

After removing the small plate from the Hydraulic head, I used UV florescent dye and light.
I found the leak. There is a hairline crack about 1/4 inch long. It is lower down than the plate was, not under it. In the morning, I will clean the HH and try to seal the crack with epoxy. The leak does not seem to be under great pressure.

Where do I buy a new head?
About what do they cost?
Are they easy to change?
Do they fail often?
How are group buys done?

Thank you all for the help and encouragement.
Rodger

 

[gimpyrobb]

Some members here have them available.
$250-550
Not too bad to change.
A lot depends on fuel quality and how much time it sits.
Kenny decides to buy another batch from china and tells everyone to send him your money.

 

[Rodger]

I have not tested the patch yet. I will this afternoon and then make periodic updates as time tests the patch. The Third photo shows the screw driver blade at the bottom of the crack. The best I can describe it the crack runs North-Northwest for about 3/16 inch. I never would have found it without the UV dye.

Rodger

 

[Heath_h49008]

JB Weld to the rescue!

Honestly, I would start looking for a take off HH and read up on the rebuild process and swap this thing out ASAP. Even if the JB holds, that fracture was caused by something you can't see without disassembly. You might be able to TIG it and save the head body, but if it were me I wouldn't feel good until I got a look at both sides of that crack.