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About Hurley88E9

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  1. Hurley88E9

    E9 Fuel In Oil

    Just to follow up, I had the injection nozzles rebuilt at Columbus diesel supply. They asked if i wanted to go with a low flow nozzle, they said it would make more power but i decided to just keep them factory. The injection nozzles were extremely dirty and all of the orings were deteriorated. I was hoping it would run a little better, the power seems the same, but there is less white/grey smoke, more than likely due to poorly atomized fuel. There really wasn't much white/grey smoke in the first place but i do think it cleaned up. After driving it a few times and checking the oil level it seems to be fixed. Thanks for the advice everyone.
  2. Hurley88E9

    E9 Fuel In Oil

    I call them injection nozzles because injection pressure is created in the injection pump, an injector creates injection pressure in the injector itself. So the way i look at it this engine doesn't have injectors. I know that is getting pretty technical, but even if you look in a mack service manual you wont see them called injectors. You are correct though, all injectors do have nozzles. Thanks for all your help. I will give an update after I get it fixed.
  3. Hurley88E9

    E9 Fuel In Oil

    The Engine has an Ambac V style pump, did all of these engines use bosch injection nozzles? I would rather have new nozzles if they are available because i could install them right after I pull the old ones. Then i wont have to wait a week for them to get back from what ever shop i send them to. Im located in Ohio, does anyone have suggestions for where i should have the original nozzles cleaned and tested?
  4. Hurley88E9

    E9 Fuel In Oil

    So this weekend i had some time to look at the engine. I pulled the valve covers and nozzle plugs and found that 4 of the nozzles had fuel on top, 2 had oil on top, and 2 were dry. So still not being 100% convinced that i was getting that much fuel in the oil from the return fuel i decided to reinstall the plugs and pressure test them. I applied 15psi to the return line on the left side of the engine and nozzle 4 started pouring fuel out around the cap. So I switched to the right side of the engine and tested it. 5,6,7, and 8 all poured fuel out. So now that my problem is pinpointed to the nozzle orings, I think i should go ahead and replace the nozzles while I have them out. What is a good replacement nozzle? Are OEM nozzles still available? Is it worth having my nozzles cleaned/tested or rebuilt? Is there a better performing nozzle?
  5. Hurley88E9

    E9 Fuel In Oil

    I might try to pull the valve covers and pressure test the return lines before pulling the caps off of the nozzles. Does that sound like a good idea? The truck has around 400k miles on it. We have owned it since 1990. For as long as I can remember the truck loses prime after a couple days of sitting, it will crank 3-5 seconds before starting and it starts kind of rough. Once it starts though it will fire instantly when you turn the key when it is restarted. It does seem like it looses prime slightly faster now that fuel is getting into the oil, but its not much faster. I changed the oil again today and it was about 2 or 3 gallons over full. I forgot to look at the speedometer but im guessing that oil had 400-500 miles on it. I will check tomorrow to make sure.
  6. Hurley88E9

    E9 Fuel In Oil

    AZB755V8 sorry i meant bypassing fuel into the oil and i edited my post. As far as the pressure check that was the lift pump i was checking, not the injection pump.
  7. Hurley88E9

    E9 Fuel In Oil

    I have a 1988 Superliner with an E9, it has the V style injection pump. I noticed the engine oil level was high and kept monitoring it to find out that it was continuing to rise. The coolant level has not moved and im positive it has to be fuel getting into the oil. The first thing I did was isolated the lift pump and applied 45psi of air pressure to the inlet and capped the outlet, after an hour i had only lost 1 psi. Next i capped the inlet and applied 45psi to the outlet and i let it sit for 14 hours, I lost 6psi. To me that does not seem like a leak that would cause my engine to be 3-5 gallon over full after 1000-2000 miles of operation. There are no new lift pumps available or rebuild kits for that style of pump. Im leaning torwards the injection pump is bypassing fuel into the oil somehow. The engine runs ok and seems to have goood power, which makes me think an injection nozzle would have nothing to do with it and by the nozzle design it would have to leak fuel past the upper oring and im sure that would cause a noticeable miss. What troubleshooting steps can i take to prove the injection pump is failing and if it is bad what are my options as far as rebuilding or replacing?

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