MEAN GTO

iTrader: (1)

Hi everyone, so I didn't really do my homework when upgrading my oil pump for my Precision journal bearing twin turbo setup a couple years ago. I put a new Melling oil pump on my LS2 and used the spring with the highest pressure. Once I got things together again the turbos were smoking due to excessive oiling. I tried oil restrictors and the only way to stop the smoking was to use the smallest jet that came with the restrictors, but seems like that must've been a really narrow stream of oil and the turbos didn't last long after that. The turbos only had a few thousand miles on them by the way-- I've owned them since brand new.

I'm building a new engine and rebuilding the turbos, and I really don't want to go through this smoking issue again. The new engine will be getting a JP double roller timing setup, and was wondering if I should be able to just keep the Melling pump (has 1k miles on it) but swap the spring and have it clearanced for the double roller setup..... or should I consider a different pump.... perhaps not a high volume pump at all????

I know SLP's pump supposedly clears the JP double roller, but not sure a high volume pump won't cause the smoking issues from excessive oil again, even with a lighter pressure spring.

Any solid advice would definitely be really appreciated! Thanks!!

-Andrew

truckdoug

iTrader: (26)

What is your oil drain situation?

MEAN GTO

iTrader: (1)

Hi Doug, I have two -10 lines going into their own -10 fittings that are welded into the very top of the front of my oil pan. No dips in the drain lines or anything. The turbos didn't ever previously smoke until immediately after installing the new Melling oil pump by the way. Thanks Sir

truckdoug

iTrader: (26)

word, we had a smoker that was due to using the cheapo -10 an fittings that have an ID of under a half inch.

also, i think it's probably best practice to size the oil pump for the engine clearances. unless your builder opened them up, sticking with the stock flow/pressure pump is a safe bet.

MEAN GTO

iTrader: (1)

Ouch yeah some of the fittings out there sure could better-fit the AN size they're advertised as haha. I'll go ahead an pick up a new GM pump and call it a day, just to be safe. I appreciate the help Doug!!

stevieturbo

I do not believe for one second the problem here is the oil pump...most notably as not once do you state the engine had increased oil pressure etc.

But with any double roller, the pump is likely to need some clearancing...AND, so is the front cover.

I actually had to clearance the DOD HV pump less than the old 296 Melling, but it was probably just small casting differences rather than any deliberate differences between them.

If the option is there though, going back to a single chain can make a lot of sense and save any worries clearancing things.

MEAN GTO

iTrader: (1)

Thanks for the info Stevie. Yeah I wasn't sure if it was worth trying to use the Melling pump but with the lighter spring. Now that I'm also feeding oil to two turbos I haven't been sure about whether or not I should stick with a stock pump.

I definitely plan on having the pump and timing cover clearanced for the the double roller. The machine shop that is putting my new short block together will be taking care of that for me, so should be no problems there.

stevieturbo

TBH, I switched from the 296 to 355 or whatever the DOD pump is, because my engine always had relatively low pressure ( compared to what some on here post anyway ), usually around 45-50psi on load. It never really changes and never was a problem though.
Likewise, 2 turbos, oil squirters etc so lots of oil getting moved although I do not restrict the oil supply to my turbos.

Changing to the HVDOD pump..didnt make a bit of bloody difference lol. Maybe just a little higher around idle etc. Unless oil pressure behaviour changes, it'll be staying the way it is.

Most of the clearancing needed is between the front cover and the pump, between chain and pump is very little.

If I was replacing the chain I would have gone back to single though, but there was nothing wrong with the double so I just stuck with it.

tech@WS6store

iTrader: (2)

Our RPMSpeed ported oil pump with std volume/pressure should fit with near zero issue and work well

ddnspider

iTrader: (26)

The issue has zero to do with the oil pump. He needs to sort out his oil feed and drain setup to the turbos.

OP....consider adding a restrictor before you Tee to each turbo. This should allow a larger restrictor but halve the volume of oil to each turbo.

tech@WS6store

iTrader: (2)

He asked about oil pumps that would fit with a double roller and possibly not be high pressure or volume. His return seems to be worked out pretty well with 10an weld bungs on the oil pan.
I answered his question with a good pump option.

ddnspider

iTrader: (26)

The OP THINKS he needs a specific pump cause his turbos died.....IRL the pump has zero to do with turbo life. Unless you want to argue that his turbos died because of his oil pump....in which case I'd love to hear your argument.

tech@WS6store

iTrader: (2)

Im not arguing with anything. He asked, i gave him an answer. He wanted clearance for the double chain, this pump does that. He went about diagnosing his issue the right way in the beginning. There are many ways to work the oil system for singlea and twins. I answered his pump question.

ddnspider

iTrader: (26)

Zero of which are related to the oil pump itself. You answered his direct question, when you should be helping him understand he asked the wrong question in the first place like Stevie did instead of immediately trying to sell a part.

tech@WS6store

iTrader: (2)

Everyone else gave him good insight but he still had questions about the pump. I answered his question, i posted a link to a part he asked about. That is what vendors do.

tech@WS6store

iTrader: (2)

The different ways to provide oil to a turbo system will depend on which pump to use as well. So yes, it does.

ddnspider

iTrader: (26)

Wow, that's tech right there.

tech@WS6store

iTrader: (2)

I apologize for triggering you with what i post.

In the effort of getting the thread back on track and not getting in trouble because i didnt reiterate what others already said, do as all the others said.

kingtal0n

iTrader: (1)

What I think they are trying to say is: you should be able to use any oil pump with any turbocharger- it isn't the pump that is the problem. It is the feed or drain line, and most likely the drain.

Most journal bearing turbos get a -4 or -6 line from the engine, unrestricted (often the hole is cast sized correctly in the turbo center section) and any oil smoking problem is associated with the drain line configs. Many manufacturers recommend (i.e. borg warner) no more than 19* degrees of tilt to the center section. The I had mine at 18* and they still were concerned even though the literature says 20* max I think. Also the position of the drain back bung in the pan can cause problems if it is an area where oil is constantly washing or splashing around, which would impede flow back to the pan. So we really need to see the engine running through a transparent oil pan to see how oil behaves at idle, and high RPM situations, before positioning the drain back bung. Otherwise, its just a guess (I guessed too ) What I Like to do is inspect oil drain back locations in oil pans used by OEM manufacturers first, to get an idea how they did it with OEM turbochargers intended to hit 200k miles.

tech@WS6store

iTrader: (2)

Using a high volume pump only to have to use oil restrictors is an issue though. Im well aware of the rest.