Stalling cummins 8.3
Greetings! I wonder if anyone out there can help me... I have a 1996 Mechanical Cummins c 8.3. I have just recently replaced both fuel filters, the lift pump and the fuel pressure regulator on the inj...
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Well... a big piece of humble pie for me! It wasn't the return line after all. I was using the Winn purge pump to test and it tricked me by straining against the back pressure of what I thought was a blockage.
It would start straining as it built up pressure in the injector pump against the new regulator. Thought that was because of the leaking o-rings? Maybe the purge pump itself is leaking? I am thinking about bypassing the Winn system altogether to single it out as a cause and just running on the filter on the engine. Anyone see a flaw in that? And how would I purge the air out of that long fuel line if I do?
To update, After Installing the new return fuel line, with new filters, i took it out for a test drive. It ran great, fueling and spooling up the turbo like normal. Filled up the tank and drove from Capital Reef NP towards Mesa Verde NP through Hite. Things were running fine until after going down the grade to Hite. I noticed a big loss in power especially on the low end again. I could get some boost if I geared it to over 2100 rpm but climbing up one of those grades I got down to 1st gear praying it would keep going. We changed plans and headed towards Grad Junction. Boost would be intermittent. watching the boost going up a grade, I could see it boost and then start falling off or gaining at random (with wide open throttle). I made it to Grad Junction and dug in further found that Winn pre-filter leaking around the o-rings. picked up some replacements and had to double them up to stop the leaks. Decided to test the CAC just in case that repair failed. Well, repair still good, an LOT of leaks still. So decided to get to Boulder where we can dig into it further. Started out and things where working great again! got up Vail pass, slow but steady, with boost even with all those CAC leaks. Got up the Eisenhower tunnel about the same but by the time I got to the bottom, I got get almost no boost again! I did make it to our destination, but now what to do next?
It would start straining as it built up pressure in the injector pump against the new regulator. Thought that was because of the leaking o-rings? Maybe the purge pump itself is leaking? I am thinking about bypassing the Winn system altogether to single it out as a cause and just running on the filter on the engine. Anyone see a flaw in that? And how would I purge the air out of that long fuel line if I do?
To update, After Installing the new return fuel line, with new filters, i took it out for a test drive. It ran great, fueling and spooling up the turbo like normal. Filled up the tank and drove from Capital Reef NP towards Mesa Verde NP through Hite. Things were running fine until after going down the grade to Hite. I noticed a big loss in power especially on the low end again. I could get some boost if I geared it to over 2100 rpm but climbing up one of those grades I got down to 1st gear praying it would keep going. We changed plans and headed towards Grad Junction. Boost would be intermittent. watching the boost going up a grade, I could see it boost and then start falling off or gaining at random (with wide open throttle). I made it to Grad Junction and dug in further found that Winn pre-filter leaking around the o-rings. picked up some replacements and had to double them up to stop the leaks. Decided to test the CAC just in case that repair failed. Well, repair still good, an LOT of leaks still. So decided to get to Boulder where we can dig into it further. Started out and things where working great again! got up Vail pass, slow but steady, with boost even with all those CAC leaks. Got up the Eisenhower tunnel about the same but by the time I got to the bottom, I got get almost no boost again! I did make it to our destination, but now what to do next?
