Normal or should be worried??

[JMBT]

When I pulled the air to air tube off the turbo, inside the turbo compressor outlet was a light residue of clean oil. It was just a residue, no actual oil sitting there. It was only in the compressor side outlet and not in the pipe or CAC inlet.
I visually checked the turbo and it looks fine. I also checked the radial & axial end play and they are fine as well. Turbo only has 180K and was brand new from Cummins not reman or aftermarket.
I wonder if this has anything to do with the exhaust smoking a bit after I have idled to warm up? Could turbo be pulling a bit of a vacuum at idle and sucking a bit of oil into the intake?

[Rawze]

(11-21-2017 )JMBT Wrote:  When I pulled the air to air tube off the turbo, inside the turbo compressor outlet was a light residue of clean oil. It was just a residue, no actual oil sitting there. It was only in the compressor side outlet and not in the pipe or CAC inlet.
I visually checked the turbo and it looks fine. I also checked the radial & axial end play and they are fine as well. Turbo only has 180K and was brand new from Cummins not reman or aftermarket.
I wonder if this has anything to do with the exhaust smoking a bit after I have idled to warm up? Could turbo be pulling a bit of a vacuum at idle and sucking a bit of oil into the intake?

Pull the IMAP sensor out of its hole (leaving it plugged in) and crank the truck. See if it has a vacuum at the intake (at the hole for the IMAP sensor) or a slight bit of positive pressure. If there is a vacuum or a heavy flutter at the intake, then the turbo needs adjusting up a bit at idle region. If it not, then it is likely just a leaky seal from the reman turbo.

- I spoke to the guy who works with Mr. Hag that does holeset turbos about just that. Guy is very good with them and there was no question/concern that he was not well versed on when I talked to him. He said to me that Holsets spec on the re-man turbo face seal is a bit too lenient on the re-mans and it is not uncommon for them to slobber sometimes. This is especially true for those who idle their truck for any length of time.

I know he has had a lot of guys who have had him replace face seals on brand new re-mans for everything from the ISX turbos to the turbos that are on the dodge pick-ups for the same symptoms. Guy also said he has seen a re-mans come right form cummins that the face seal was not even replaced. Don't know if I believe that one or not, but I have seen the problem a lot both on de-mandated trucks and stock engines alike equally.

[JMBT]

Thanks Rawze, I will pull the IMAP and check for vac today and let you know what I find. On the seal, this was a brand new turbo from Cummins, NOT a reman. I fought like hell to get it about 180K ago. Cummins kept telling me new turbos were not available until I found one dealer that sourced me a brand new one from the factory line. $4450 without the actuator. Hopefully it wouldn’t be leaking yet? We’ll see.

[JMBT]

Rawze, I just checked and I have positive pressure at the IMAP hole at idle. It is a slight puff-puff-puff feeling on your finger.

[Rawze]

(11-21-2017 )JMBT Wrote:  Rawze, I just checked and I have positive pressure at the IMAP hole at idle. It is a slight puff-puff-puff feeling on your finger.

Positive pressure is a good sign. There is no reason it should be leaky.

Maybe stop by that guy Mr. Hag uses and have the face seal inspected / changed if it gets any worse?. That way someone can evaluate why it might be leaky.

Also, ensurte your crank case filter is drilled out or you have that service free one. A dirty or clogged crank case filter will make one bleed too.

[JMBT]

Thanks again Rawze! I’ll keep you posted.