Rb25 eating turbos

[bmxarmy]

Hey guys,

Seems like the Rbambler has a taste for turbos these days.... Being that turbos are a relatively simple piece I feel I have covered my bases here and am at a loss!

Here is the story. When the rb first made it into the rambler I bought a used hx35 and ran it as is, It did have slight shaft play side to side but in and out was ok. It lasted aprox 300 miles, the car started to blue blue smoke when I shifted. Found the the turbo to be totaled with so much side to side shaft play the compressor wheel hit the housing.

Round 2 another hx35 this time rebuilt by me, The rebuild went well however some of the specs where on the far end for good going off factory specs. Also I never got it balanced after it was rebuilt. ( Maybe I should have done that) It lasted another 300 or so miles until the same thing happened. Ran hard then blue smoke when shifting and turbo had crazy shaft play/damage.

Third time is a charm right? NOPE! This time I buy a brand new turbonetics 60/61 T3 flange turbo. It lasted a 1/4 tank of fuel! I have a good solid feed coming from the factory location and a 1" drain line directly to the pan. Turbo is on its way back to turbonetics now for a hopeful warranty. but we will see I guess.

Anybody have similar problems before? Maybe I just have bad luck and the first turbo was on its last legs, 2nd rebuilt poorly, and 3rd a factory problem? Please give me something! I am going crazy and poor at the same time here!

Nolan

[Coolwhip]

Sorry to hear man. The 1" drain sounds kind of big. You could be pulling enough vacuum in the crank case to pull oil out of the turbo with such a large drain before it fully lubricate the turbo.

We had a twin turbo mustang build awhile that ended up with a -8an on each turbo to prevent this from happening. Then again the motor was equipped with a vacuum pump.

Just a thought.

[jetdriver]

Whatever you put on next, run the drain into a clean bucket and idle the motor for about 30 seconds and measure how much oil is going through the turbo. It sounds like a supply problem. Are you running any restrictorson the feed line?

[bmxarmy]

No restrictors on the feed other than the mandatory one that comes on a turbonetics turbo. I started the car, with the turbo removed and put the feed line into a pop bottle....Filed 1/4 of the bottle in like 10-15 seconds. Drain line may be to big.....I cut off the factory drain line aprox 6" below the turbo and ran rubber hose down to pan. I can take some pics of it now and post them up.

[robbie2883]

what's your oil pressure like at idle and at rpm?

[Carl H]

are you using a fitting on the side of the block or are you using the factory banjo bolt?

factory banjo has a built in restrictor.

[bmxarmy]

Factory banjo got put on a new line....I didnt know there was a restrictor in it.

50-60psi of oil at initial start-up drops to 35-40ish when warm.

Could the factory banjo be restricting too much flow?

Thanks Guys! Im desperate here! haha

[Carl H]

yeah, the actual bolt its self has a restricter and the metal line/banjo does as well; no idea how you made your feed but when i build feeds i normally drill out the restricter in the banjo and the line and add one at the turbo if needed.
stock turbos are ball bearing so they need a rather small restricter where as the journal bearing turbos need quite a bit more oil.

try that first, if anything you've just made a mess on the garage floor.
if it is restricted then a few minuted with a drill bit should solve the problem.

[julio]

Call me paranoid, but I always check oil pressure right before the turbo/restrictor at idle and at operating speed.

[bmxarmy]

PARANOID!!!!

J/k, What is a guy expecting to see as far as pressure at these rpms? Seriously this is the last time I want to f*** with a turbo on the rambler for a while! I will check EVERYTHING if I have to.

[julio]

Call me paranoid, but I always check oil pressure right before the turbo/restrictor at idle and at operating speed.

Correction, I meant before the turbo, but after the restrictor. Basically just checking to see what pressure the turbo is actual seeing.

Oil pressure depends on what the manufacturer calls for. Holset calls for ~15 psi at idle, at least 30psi at operating speed, and no more than 60 psi overall i believe (at operating temp). If you get your turbo back from turbonetics, just ask them what they call for.

[OutToWinPAHC]

Most issues are seals they are there to keep boost out of the center not keep oil out. So proper clocking and draining is a must. Now rebuilding a good turbo at home is not bad, rebuilding a bad turbo at home is horrible. Reason is when the turbo goes out of balance the machined clearances on the housing can also go out of spec. So if you build your turbo with a good kit the seals may not be in tolerance and you just wasted time and money. It's best to have it rebuilt where they check this, because the seats may need machining and over sized seals may be needed. Shaft balance is also a must in my book.

[ST240]

I had the same issue.

Are you running the stock manifold? I had the stock manifold + brand new HX35 = mega restriction. Potentially add this to pulled timing up top and you've got 1200 - 1400 EGTs during WOT!!

IMHO the high EGTs are what cooked my brand new HX35. Have you checked your EGTs?

[DA 240]

I had the same issue.

Are you running the stock manifold? I had the stock manifold + brand new HX35 = mega restriction. Potentially add this to pulled timing up top and you've got 1200 - 1400 EGTs during WOT!!

IMHO the high EGTs are what cooked my brand new HX35. Have you checked your EGTs?

I'm running somethign similar and I have to admit I haven't put that many miles on my setup. When you say "cooked" do you just mean the bearings?

[Carl H]

1400f = 760*c, not hot at all.
my car runs 850*c peak boost, turbine wheel is perfect...

stock manifold flows quite well actually, its not as bad as you might think.

[ST240]

Actually I think it was even hotter than that. 1800 or so. Also this was on my RB30. But yeah maybe the stocker isnt as restrictive as I think.

[ST240]

I'm running somethign similar and I have to admit I haven't put that many miles on my setup. When you say "cooked" do you just mean the bearings?

Yeah the bearings, shaft play became excessive and the compressor started rubbing the housing, throwing the whole thing out of balance.

[robbie2883]

aluminum melts at 1600....so 1800 for any prolonged period is not good. i would look at the tune

[bmxarmy]

feeling good on the tune, I am really hoping it is just the oil feed line. What did you do to solve your problem ST240?

[DA 240]

feeling good on the tune, I am really hoping it is just the oil feed line. What did you do to solve your problem ST240?

I'm also interested on how you (ST240) solved your problem.

[ST240]

So yeah I did have temps in the 1800-2000 range (no s***), timing was really retarded though, maybe 10*?

Without changing the tune, ditched the holset for a 6262 and ditched the stock manifold for a chinese tubular one (which probably doesnt flow that great anyway, but maybe better than stock), and temps were down to around 1400. Keep in mind this was on a RB30 with RB25DE head.

[Carl H]

10*?!?!?!
man that is too little timing!

my car wouldnt run worth crap at 15*, when all was said and done she got 26* and loves it!

[robbie2883]

10*? no wonder your egt's were so hot....you were probably spitting fuel into the turbo manifold and then igniting it.


nolan...when i mentioned the tune i was referring to st240's high egt's. sorry for the thread jack

[bmxarmy]

NP, good read so far! haha

Will keep everyone posted on the banjo restrictor issue, Waiting on the "new" turbo before I pull the ol girl back in the garage.