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Hurley88E9

E9 Fuel In Oil

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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?

 

Edited by Hurley88E9

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I would chectk the injectors before blaming the pump lift the valve covers off and pop out each injector hold down check for fuel on top of each injector! Injector oring failure will cause this as well!

Edited by fjh

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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.

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>. The only way that would happen is if there was back pressure in the return lines. Is that correct?<

The only way is by the orings That I HAVE SEEN . 
I  by no means am saying the fuel pump is not at fault ! But The orings get hard and cooked and crispy  over time and fuel starts passing by the return orings IF  it cant go out the injection line spacer( Another indicator) wet or damp injection lines!   it  takes the path of least resistance depending on the return line drain back valve spring tension and engine RPM any where from 30-60 psi! I have worked with a fair few V8s  over the years and have  rarely Had a fuel pump or transfer pump fail in this manner! I have had quite a few injector orings get crispy Thou  !

 

Just Sayin ! 😉

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Thanks for the information on the O-rings. It is more than likely the problem and the least expensive to fix. 👍

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Yup!😎  As a side Note You only Need to install the top big and the second small  oring down on the injector the metal washer at the tip will seal the return gallery just fine!

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2 hours ago, fjh said:

Yup!😎  As a side Note You only Need to install the top big and the second small  oring down on the injector the metal washer at the tip will seal the return gallery just fine!

Yes on two O-rings and washer. Some injectors only have two O-ring grooves. I am just putting injectors back in from the pump shop. Newer ones have 2 groove from Turkey, Older ones have 3 grooves from Bosch. This engine was missing and had low RPM idle, one injector was bad out of the 8, it was the one with fuel on top of injector and under the cap... that should solve my issue.

Newer injectors have military nozzles, but so did the old ones!!  👍  It's a big bad runnin Puppy.

IMG_2374.thumb.JPG.dc276281a273578e81e2412be7da59d9.JPG

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Those injectors are from a Robert Bosch straight pump engine identify able by the ball alignment  dowel

Edited by fjh

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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.

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Just pull the plugs it takes half an hour and some new valve cover gaskets. Just my opinion!

To prove out the situation if there’s fuel on the top of the injector s time for orings

Edited by fjh
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My Dad had a  brand new CL in 94 with an E9 it did that within the 2 years he had it . I would bet money it’s  an injector o ring giving you grief . I’d start there cheap fix and  you’re back going in  a couple hours . 

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13 hours ago, BAD DOG said:

My Dad had a  brand new CL in 94 with an E9 it did that within the 2 years he had it . I would bet money it’s  an injector o ring giving you grief . I’d start there cheap fix and  you’re back going in  a couple hours . 

Yup correct! My half our comment was based on a look see! NOT A repair!

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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?

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12 hours ago, Hurley88E9 said:

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?

The O-rings are the issue, replace them, it is an EZ fix, get the O-rings from a Bosch injection shop. Take the injectors to a Bosch injection shop and have them cleaned and have the opening pressure checked and brought back to factory spec. The opening pressure does change over time and a different shim under the injector spring is all it takes to get it right and setting it with the proper equipment. Let the pump shop tell you if the nozzles need replaced they will check the spray pattern when they are cleaned. 

Edited by AZB755V8
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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?

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The nozzle is the tip portion of the injector body. All injectors have nozzles it does not matter how makes them. You can not just replace the nozzles on the injector body at your work bench. This must be done at a fuel injection shop to get the proper opening pressure and check for spray pattern with new or used parts. If you get the whole injector with nozzles to replace the ones in your engine that would be a lot of money that you do not need to spend. 

If you just want new nozzles then tell the shop replace then even if they are not bad. That may take time to get them ordered in. Southwest Injection in Phoenix is who I use and they had my injectors  cleaned, pattern checked and opening pressure set, back to me the next day. It can't get any faster than that. If your shop takes a week you might tell then to put a RUSH on on it and pay a little more for the RUSH service. Columbus Diesel is a good shop, in Columbus Ohio that I would recommend, talk to Dan there.

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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.

 

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13 hours ago, Hurley88E9 said:

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.

 

Just splitting hairs here  ! The  pressure would not be complete with out the injector its all in the package ! it sets the pressure and and the spray as stated ! Just get it done! If you need to run the truck THEN  just pull em clean em and put em back in with new orings  ! Chances are injectors will need to benched to change tips ! Also stated. exchange will likley be next to impossible to find  (happy hunting ) This will shut you down for a week   while you wait for them! if you don't need the truck by all means send em out get new tips put on!or wait to find some exchange ones!

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On 12/17/2018 at 5:29 PM, Hurley88E9 said:

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.

👍

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