Fuel leak

[TNelson]

Just bought a 1990 E-350 with the 7.3 IDI. Has a pretty steady fuel leak that runs down the back of the motor. Just changed the o-rings on the injector returns...Don't know much about this old truck, but familiar with diesels in general..TIA Gentlemen

[sea71]

I dont know a lot about the OBS style truck, but there will be someone along in a few that can help ya out. Welcome to the site!!

[TNelson]

Thanks for the welcome. I am looking forward to learning about this old truck and geting ahead of its quirks and common problems

[sea71]

Free bump back to the top.

[Big AL]

Welcome to the Site. Stick around - you will get some info.

[gbear]

I've not worked on that year, but I would check the rear cyclinder injector lines. since Its an E series pull the dog house and give it a good inspection with it running.

Jim

[gbear]

Maybe someone with more first hand knowledge will jump in and help out

Jim

[TNelson]

I changed out all the o-rings on the injector returns and the rubber return lines. I also replaced the hose clamps with new ones. I had the dog house off to do that work. The leak is not originating with the injectors, seems to be running on the valley pan under the air intake from the front. I lose track of it under the plenum and with all the accessories and the injector pump right in front of the plenum I can't seem to find the leak from the front or track it past the plenum. I'm leaning toward a leak from or near the injector pump. Anyone ever ran into this or a similar??

[ats85]

Even after I replaced mine, I still chased leaks. The plastic caps needs to be lubricated w/ diesel or wd40 before pushing them on, and they must seat all the way down, sometimes you have to twist them slightly. is it possible you tore an o-ring installing? If its a high pressure leak, the engine will usually have a miss? Did you check all the fittings on the IP pump?

[TNelson]

After replacing all the o-rings and the fuel return lines I discovered my leak was indeed due to a faulty hose clamp on the #1-#3 return line, replaced all hose clamps and now have a dry motor. Thank you for your help in solving this problem.