Injection Pump leak

[LOGGJAM]

Hello All, my name is Mike and im from PA, i just became a member a few days ago...

I have recently bought my first MV it's titled as a 57 REO M35 and i have all the problems worked out except one and that is a fuel leak which i cannot seem to find where it is starting from it has a Hercules multi-fuel with ~580 hours on it, the the leak appears to be comming from somewhere on the hydraulic head of the IP but it does not leak while idling or on fast idle, it will only leak when engine is under load, i can run it through the gears once, stop and check and the IP will be wet with fuel, there is a 12 point 7/16 plug (at least i think its a plug) on the side of the hydraulic head which could be where the leak is comming from because the fuel on the IP is not any higher than that point, it doesnt appear to be leaking from any of the lines...

any ideas would be greatly appreciated, ill try to get some pics up soon...

 

[Goatwerks]

To pin point the leak, first clean suspect area with brake cleaner and let dry, then take a can of spray foot powder or powder anti persperent and spray it all over the suspected area and let it dry.
Now run engine till it starts to leak, shut it down and look for sags in the powder, at the top of the sag you will find the source
Very easy and cheap method to find all clear liquid leaks

 

[Victorious1!]

My deuce does the same thing. I havent found the souce yet. It only does it under a load. I pulled the throttle and got out to see if it would do it at high idle but no luck. Mine seems to get completely saturated all over the I/P head. The plug on the side which you speak of is some sort of check valve (I think) it can be ramoved with a 7/16 box end wrench but be careful, theres a small spring that fell out onto the ground and I never did find it. had to buy a new one. There was no gasket or o-ring on the plug and I confirmed with my parts guy that it doesnt call for one. Im thinking mine might be a bad injector line. Let me know if you figure yours out.

 

[thehaas]

fuel injector lines compression fittings bad even if you tighten lines.real slow leak pull off rubber boots clean with brake clean blow off let idle and watch fuel leak.replaced all mine no leak

 

[LOGGJAM]

Thanks All for the ideas, found that it was the hydraulic head plug that was leaking, got one in the mail from BOYCE Equip. today all is good no leaks ran it for ~50 miles today!!

 

[derby]

Are You talking about the plug in the top or on the side? My truck does the same thing only leaks under load.

 

[LOGGJAM]

It was the plug on the side of the head, with the spring and needle valve inside, only replaced the plug and spring, due to spring landing in a stone driveway never to be seen again, 7/16 12 point torqued to 22 ft lbs

 

[m-35tom]

this is a check valve and is a very important part. is the valve still there?

 

[LOGGJAM]

yes the valve stayed in there just the spring fell out, checked to make sure before replacing the plug