Turbo engine rebuild (New Title)

[clownmidget]

Will do, there was indeed oil throughout the entire air ducting of intercooler all the way through throttle body, then intake manifold. On the intake manifold runners 1,2,3,4 & 6 were all liberally coated with oil but #5 was spotless.

The oil system was completely pressurized though given the gap around the piston, so it was blowing oil vapor out the exhaust valves, into the hot side turbine, so it will be interesting to see how the turbo checks out.

 

[Tapage]

If the oil was coming from the center section then the inter cooler is likely full of it.

thought if a good amount of oil was found in the intake that can take an effect in the MAF sensor and maybe bad reading mixture failure .?

 

[landtank]

thought if a good amount of oil was found in the intake that can take an effect in the MAF sensor and maybe bad reading mixture failure .?

the MAF sensor is on the low side of the compressor which is pre turbo and safe from this sort of failure. The lines out to the inter cooler and up into the intake are all on the high side.

another thought might be that the engine block was being pressurized by the turbo in some way.

There a two hoses coming off the top of the valve cover. One is the PCV valve (DS) and the other is a vent line (PS). During the install the vent line gets moved to the low side of the air intake pre turbo.

So if the block were to be pressurized the oil would be forced out through the vent line directly to the intake of the compressor housing.

So look around that area as well.

 

[clownmidget]

Yes, MAF, air cleaner box, air filter, all clean. ( but the PO did put a K & N in there

the PCV seemed to be relatively clean and worked fine when MoGas came over when the truck was still in Flagstaff.

Vent line was FOUL....

with the oil fill cap off and oil poured into cylinder #1, when we turned it over to test for compression, it would puff out oil smoke from the oil fill hole like a steam locomotive!

 

[Tapage]

the MAF sensor is on the low side of the compressor which is pre turbo and safe from this sort of failure. The lines out to the inter cooler and up into the intake are all on the high side..

that means the MAF never get the info of the right ( presurized ) amount of air entering in the intake manifold ?

 

[landtank]

that means the MAF never get the info of the right ( presurized ) amount of air entering in the intake manifold ?

At any given time the amount of air coming out of a turbo is the same that is going in. Only it's characteristics have changed.

 

[akarilo]

I may have missed it somwhere, but how many psi was this setup running?

 

[clownmidget]

Unknown. The factory setting is 6 psi but it had a turbo timer set up that can alter boost. The read out was in MPa not psi and is absolutely tiny.

 

[wayneosan]

IMO.

To me it looks like it ran lean. Melted piston equals really freaking hot.
Probably some detonation there too, but, none the less, it got waaaay too hot.

Again, IMO. I've used Uni-Chip in the past. I use "past" as in no one touches it anymore. For this reason.

Sorry to hear about that man. I have a good engine that was freshly rebuilt from my 92 I'm taking out. Literally 1500 miles on the rebuild, if you need one.

Sounds like you were excited to get er home!!! Kinda like bringing the girlfriend home for the first time. This was just a bad first date...

 

[alia176]

Here's the melted piston.

 

[wayneosan]

that'll make a good paper weight...

 

[sparkplug]

Well you're entitled to your opinion ...but for now there is no clear idea of what went wrong or why, so the jury is still out.

And these motors handle boost just fine if maintained properly. Please show me a 200K mile Cheby motor - a)that actually still runs without burning as much oil as petrol and b)that is honestly as dependable. I grew up on American V8's. Cheap, straigtforward power - no doubt. But long term reliability? Longevity beyond 100K miles of punishment? Please. Tear down the two and see the internals. My previous 80 (Now in Costa Rica) has over 100K of being boosted, and over 225K total, on the same bottom end, HG replaced preventatively @ 175K miles.

To be honest, this was a rookie mistake on my end. I showed up, hopped in an unfamiliar truck that had been sitting for months, never really base-lined anything, nada, and started driving it across country. I know now I should have take a day or two and really gone through the coolant system, turbo system, etc. and been vigilent but I was pinched for time and cut corners. I should have, and do, know better and this is the result. But these guys and this forum has been immensely generous and helpful and absolutely the best but their drinking expenditures account for 95% of the budget

And your old cruiser is still going strong! It is my daily driver when I am down there. I have put about 17k on it and thrown zero codes. The only problem I had was the front shocks unthreading because of pounding down horrible pothole filled trails.


Sorry to hear about your problem Mike. I hope you get it sorted out.

 

[Tapage]

At any given time the amount of air coming out of a turbo is the same that is going in. Only it's characteristics have changed.

yap .. I would change my words .. compressed air, contains more O and in the same line this compressed air it's more hot which affect the density of it ..

then I thought the MAF reading pre turbo are not that accuracy enymore to help the stock ECU keep the 14.7:1 ideal mixture ..

 

[landtank]

that might provide a nice path for pressurizing the block.

 

[clownmidget]

Update: block being bored over for 1.0-mm over Toyota pistons & rings

Injectors still not back from RC Eng

Nothing else until stuff is finished at machine shop.

 

[akarilo]

You guys are going to town on the progress!

 

[OGBeno]

Nothing else until stuff is finished at machine shop.

Which will be next week...also when Mike flies in and we start the assembly process.

 

[Romer]

Which will be next week...also when Mike flies in and we start the assembly process.

Onur, you and Ali always impress me with your being there to help out when ever needed

 

[silverhorse]

Yes he does. I'll keep that info stored in my memory bank for later use..

 

[alia176]

Onur, you and Ali always impress me with your being there to help out when ever needed

I don't know how much help I'd be if I had a freaking job