keep smelling diesel under hood

Porno Joe

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Oct 11, 2010
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South of Pittsburgh
so over the past few months I continue to smell diesel under my hood, it seems to be coming from the drivers side. however I have no leak that is leaving any kind of drops on the floor. I have looked under the hood and I am not seeing any obvious signs of a leak. Also there is no major drop in mileage to go along with a serious leak. just getting annoying constantly getting a whiff of raw diesel

I have dual pumps so it could be from the 2nd injection pump possibly

I can see what looks like a slight film on the injection pump behind the pulley, but otherwise I see no visible signs of a leak.

I'm thinking it would have to be a low pressure line, as high pressure would have fuel squirting everywhere, no?

So the low pressure side of things to check would be:

1- injector return line
2- 2nd cp3 feed
3- 2nd cp3 return hose.

anything else I missed?

I was just under the truck the other night looking at my leaking steering stabilizer and the underside of my motor is bone dry. so whatever this is has to be small enough to not drip down or its burning off on the manifold and that's what i'm smelling?
 

Porno Joe

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Oct 11, 2010
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Think I found it:

4a7312168ea2bcb47a6c55323c62b271.jpg


This is the back of my pulley on my 2nd cp3. It's obviously getting damp and all the dirt and dust is sticking to it. Wiped my finger in it and it smells like diesel.

So is there a seal somewhere on the front of the cp3 I can change?
 

Porno Joe

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Oct 11, 2010
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I just narrowed it down. I'm fairly certain I t's coming out of the front of the cp3. There is no signs of fuel anywhere on the motor. It's there and then under the pump.

I googled and there are 2 seals on the shaft. Anybody know where I can buy them?
 

Porno Joe

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Oct 11, 2010
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Drove roughly 85 miles today. Smelled diesel when I got home and popped the hood. Diesel on the wiring for the dual pump controller. So has to be coming from the 2nd cp3.

Where can I get a seal kit?
 

Porno Joe

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I paid like $70 with shipping for mine.

Got it all done Friday. Soon as I removed my 2nd pump I could see the diesel coming out the shaft seals.

Haven't driven it yet but it went together smoothly
 

Porno Joe

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I bought my kit from:

Philadelphia Ball and Roller Bearing Co.
1346 Centre Ave.
Reading PA `9601
Phone: 610-376-7500

I got their info from a Cummins forum. As soon as I told the guy I was looking for injection pump seals, he said "oh ya we made a kit up for those a few years ago". Apparently someone on the cummins forum lived in reading and took his pump in. They tore it apart and went thru it matching up all the seals and O-rings.

Their kit contains the two shaft seals, and the o rings. you have to split the pump in half where the aluminum and steel meet. The shaft seals were exactly like what I removed.

The only "issue" I had with the kit is the 6 small o rings appeared to be TOO small. It may have just been mine were flattened so much they appeared bigger.

I'll do a write up on the R&R tonight or tomorrow. I didn't take that many pics since no one replied wanting a DIY prior to me doing it. Granted my pump is the top pump in the dual cp3 setup, so removal was much easier that if in the valley, but start to finish took me less than 2 hours.
 

Porno Joe

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I won’t go into detail on how to remove the pump from the truck; I’ll start with the pump off on the workbench.

Once I had my pump off my truck it was obvious my inner seal had failed- you could see the diesel running out of the shaft.Also if you see diesel leaking out of the shaft, you cannot simply replace the outer seal only!The inner shaft seal is the one that must be replaced.

Here is the list of parts included in the kit:
1- 25mmx36mmx7mm harwal seal (Inner CP3 shaft seal)
1-25mmx37mmx7mm harwal seal (Outer CP3 shaft seal)
1-2.50mmx54.00mm ame o-ring
6-2.00mmx7.00mm ame o-rings
1-2.00mmx67.00mm ame o-ring

1. Make sure your work area is clean clean clean! Set the pump down on the clean surface with the shaft facing up.You may want to remove the fuel pressure regulator to avoid accidentally damaging it.

2. Remove the 6 T-30 torx bolts from the face of the pump.

3. Turn the pump on its side and lightly tap the aluminum front of the pump.It should ‘pop’ loose after a good whack.

4. When you split the pump, be very cautious- the small o rings could fall out.I was fortunate in that all of mine were stuck to either side of the pump.I removed them from the aluminum (front) piece and placed them all in the rear section of the pump, since we will be working on the front.

5. Place the front of the pump in a vise.I clamped the pump between two pieces of scrap wood to ensure I did not damage it.

6. With the exterior of the pump facing you, remove the outer seal.I used a standard seal puller tool, and I put a scrap of wood on the pump where I was prying for leverage so I did not damaged the aluminum.A thin piece of wood like a popsicle stick will work.

7. Once the outer seal is removed, remove the large snap ring.

8. Turn the pump around, working from the back drive the inner seal out the front of the pump using a long punch and hammer.I found this the simplest way to remove the inner seal as it is so deep you cannot easily pry on it.

TRIPLE CHECK YOU HAVE THE CORRECT SEAL BEFORE INSTALLATION.The inner seal is 1 mm smaller than the outer seal and it can be easy to mix them up if you are not paying attention.

9. Install new inner seal.I used a large stock (I believe 1 1/8) which was almost the perfect size as the inner seal to seat the seal.

10. Replace snap ring.

11. Install outer seal.I used the same socket to tap it into place.

12.Set front half of pump face down on workbench.You will notice 2 large o rings where the aluminum and steel halves of the pump meet.Replace both of these with the o rings included in the kit.

13.As noted above, I did not replace the small o rings as I was not sure they were the correct size (pic in following post)

14.Before attempting to reassemble the pump, ensure both mating surfaces are clean!I had a lot of debris fall onto the surfaces when I split the pump.I used some spray cleaner and wiped down both surfaces.

15. gently side the aluminum front half onto the cp3 shaft.You should be able to put it down far enough by hand to get the torx bolts started.I tightened in a crisscross pattern.I do not know the torque spec but these were not very tight.

16. reinstall fuel pressure regulator if you removed it.

You are done! Reinstall your pump on your truck.
 

Porno Joe

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Oct 11, 2010
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South of Pittsburgh
This is odd; I can't say I've ever heard of a cp3 needing to be resealed before.


think its because there is no info out there about how to replace seals. most guys have a leaking cp3 and just buy a rebuilt one.

the aluminum front half of the cp3 has a weep hole in it if the inner seals fails. however I would think that would more than likely end up leaking inside the crankcase on a dmax if this was your pump in the valley. since mine was my 2nd cp3 it was leaking out the shalf and down my bracket.
 

BLACKMAX1

WAY2EVL
Jul 10, 2013
555
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VA beach
My pump has the same issue, I got ahold of the guys at Philadelphia Ball and Roller Bearing Co their gonna send me the kit. Said it won't ship till next week because they are waiting on some of the smaller orings. Thanks for sharing the info.
 
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