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When to rebuild turbo
Posted by: Doug64Vair ()
Date: June 28, 2020 02:24PM

I have recently gotten by '64 Spyder back on the road after at least a 10-year slumber. As to be expected, there was/is a great deal of sorting out to be done. I rebuilt the carb, installed all new brake system, repaired various electrical issues. I even got to rebuild the four-speed and replace the differential after the pinion bearings seized and snapped the mainshaft in two. Fun.

All that is behind me now, and she's on the road. My problem is that I have yet to see any boost on the gauge or feel it in the small of my back. I have verified that the turbo can spin, even going so far as to oil the bearing manually through the oil feed line and spinning it with a drill by reaching through the inlet and turning the nut that holds the turbines together. It won't freewheel, but it doesn't bind, either. There are no obvious exhaust leaks, but I am considering replacing all the exhast gaskets anyway.

The tech section in the Clark's catalog mentions a few things to check, all of which necessitate disassembling the turbo. I am not opposed to doing this, especially since I can see some of the cold side impeller blades are damaged. I just want to be sure that there isn't a simple fix that can be attempted prior to getting into the unit or anything I may be overlooking.

Any thoughts, Corvair folks? And does anyone have any good used turbo pieces lying around, should I find a housing full of junk if I do tear it own? I suspect that my damaged cold side turbine isn't doing much for keeping the unit in balance, so I would like to change that out at least if I open it up AND one can be found. I would be buying the rebuild kit from Clark's, most likely.

Thanks -- Doug

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Re: When to rebuild turbo
Posted by: 2ragtops ()
Date: June 28, 2020 02:50PM

PM sent

Bob Bauer

Show-Me Corvairs

1966 Monza Convert 140 P/G with A/C, plastic wheel with tele-column am-fm posi-traction
1966 Corsa Convert 180 wood wheel tele-column am-fm sport steering posi-traction
1965 Corsa Coupe Crown V8 temporarily red lined for repair
House Springs, Missouri

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Re: When to rebuild turbo
Posted by: steve c goodman ()
Date: June 28, 2020 03:20PM

Did you look at condition of blades on both wheels?

If good I would check throttle linkage to ensure WOT when pedal is on the carpet. Check exh leaks by plugging muffler extension while eng is ixls speed. If tight eng will die in minute or two. Muffler also can be plugged inside if old.

More common checks are timing at 24 degrees plus correct distributor. Hot spark from good coil. Air filter element clean.

Good luck too. Boost is addictive. ggg

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC/V8 Registry

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Re: When to rebuild turbo
Posted by: 63turbo ()
Date: June 28, 2020 03:28PM

Another good thing to check is the clearance between the exhaust turbine and its housing... there have been more than a few where "someone" inadvertantly put an
f-flow (late) exhaust housing on the smaller b-flow... resulting in a large gap and NO boost no matter what!

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car



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Re: When to rebuild turbo
Posted by: steve c goodman ()
Date: June 28, 2020 03:54PM

Doug64 did turbo work before? Was anything done to it while car was down other than storing on a shelf?

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC/V8 Registry

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Re: When to rebuild turbo
Posted by: v8vair ()
Date: June 28, 2020 04:38PM

Check for exhaust leaks

1965 Crown V8 Racer
1964 Bill Thomas Monza Replica Racer
1964 Spyder Street Car
1979 Mazda RX7

Mike Levine

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Re: When to rebuild turbo
Posted by: DOUG WARD ()
Date: June 28, 2020 05:57PM

I was me that had the experience of an incorrect turbine blade in a 180 housing. The P O had swapped out the turbo on my 65 180 with a 64 turbo. It has the smaller turbine blade. He mounted it on the original 180 housing. It would not make ANY boost, due to the 65 housing having a larger scroll than the 64 turbine could feed. What I ended up doing though, was to keep the 64 cold side impeller and it's housing (it's smaller in diameter & spins up quicker than the 65 one does.) My car is now pretty quick. I can get boost in the top of 2nd,& it gets about 10 to 13 lbs boost in 3rd & 4th. Also, make sure that you have the correct 65/66 carburetor, as it also has a larger venturi than the 62 - 64 models. The next mod I'm going to try is to go to a side draft Weber carb. I have one with a Crown adapter that will bolt right on. The linkage has to be slightly modified and I think it's Seth Emerson that does a throttle shaft mod to the Weber that allows for a primary plus secondary operation of it.
Best of luck with your turbo Corvair. They are a kick in the pants to drive. Doug Ward

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Re: When to rebuild turbo
Posted by: Doug64Vair ()
Date: June 28, 2020 06:59PM

Thanks all, for the suggestions. To answer the questions:

Steve:

I have only looked the cold side turbine with the carb off. The hot side is as yet untouched. I figure if I remove enough hardware to see the exhaust side wheel, I might just as well take the whole thing off and work it on the bench.

As far as I and the PO know, the engine hasn't run at speed on the highway for about 10 years. He drove it off a trailer, watched it leak oil badly from the push rod and oil cooler seals, and parked it inside a hangar for a decade. The only thing that was done was draining the oil so it wouldn't all leak out. Nothing was removed. Fortunately it had aviation fuel in it during this time. So to answer your question, the original condition of the turbo is unknown.

All that's been done to the turbo is some external cleaning, turning the turbine for maybe two minutes with a drill, about 60 miles of driving to get clean, hot oil into the turbo bearings, and wishful thinking that it would magically start spinning again. No such luck.

I will try the exhaust leak test and recheck the timing and get back to this post with the results.

Thanks!

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Re: When to rebuild turbo
Posted by: alan_smithee ()
Date: June 28, 2020 07:41PM

i had a similar problem with mine when i first got it. car had not really been run at highway speed for over 5 years. A couple of months later with some "spirited driving" on really warm 90 plus degree days going up and down some hilly driving keeping it under the load, the turbo just started kicking in. And boy did it kick in! My guess is that carbon buildup needed to break loose.


Doug64Vair Wrote:
-------------------------------------------------------
> Thanks all, for the suggestions. To answer the questions:
>
> Steve:
>
> I have only looked the cold side turbine with the carb off. The hot side is as yet untouched. I figure if I remove enough hardware to see the exhaust side wheel, I might just as well take the whole thing off and work it on the bench.
>
> As far as I and the PO know, the engine hasn't run at speed on the highway for about 10 years. He drove it off a trailer, watched it leak oil badly from the push rod and oil cooler seals, and parked it inside a hangar for a decade. The only thing that was done was draining the oil so it wouldn't all leak out. Nothing was removed. Fortunately it had aviation fuel in it during this time. So to answer your question, the original condition of the turbo is unknown.
>
> All that's been done to the turbo is some external cleaning, turning the turbine for maybe two minutes with a drill, about 60 miles of driving to get clean, hot oil into the turbo bearings, and wishful thinking that it would magically start spinning again. No such luck.
>
> I will try the exhaust leak test and recheck the timing and get back to this post with the results.
>
> Thanks!


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Re: When to rebuild turbo
Posted by: steve c goodman ()
Date: June 28, 2020 07:49PM

Wishful thinking it would start spinning again?

Turned with drill motor?

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC/V8 Registry

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Re: When to rebuild turbo
Posted by: steve c goodman ()
Date: June 28, 2020 08:49PM

Doug64 I just read your first post again and you say damage to compressor wheel. Remember if compressor side comes apart the pieces go into pistons/heads.

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC/V8 Registry

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Re: When to rebuild turbo
Posted by: vairmech ()
Date: June 29, 2020 04:53AM

Steve prompted me to go back and read the first post, damaged impeller doesn't mean chunks missing. I've seen damaged impellers without being broken, very inefficient, yes.

We can't ASSUME the damage was catastrophic failure of a piece coming off. He could just be seeing small debris marks and call it damaged.

I think we need a better description of what was seen!

Ken Hand
Handy Car Care
248 613 8586

Vairmech@aol.com

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Re: When to rebuild turbo
Posted by: zarfnober ()
Date: June 29, 2020 05:03AM

I had a compressor side explode once, and yes, the parts go everywhere! My brother used to drag race a turbo Harley(8.22@168mph) and during a lean condition on nitrous, literally vaporized a couple valves, no damage internally to the engine.

As for boost, or lack of it, my wife had a turbo Sonata, a friend insisted she test drive his hybrid Sonata.

“I tried to make it go turbo, but it wouldn’t do it”. She now has a GTI and refuses to get ever get any car that isn’t boosted.

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Re: When to rebuild turbo
Posted by: steve c goodman ()
Date: June 29, 2020 05:19AM

Ken is correct the word 'damage' takes many meanings.

Many of us jump to conclusions without knowing all of the details (or missing words) and it is just guesses.

best wishes, Steve
Rear Engine Spec. Inc. Golden, Colo.

1962 spyder 3.0L turbo---1965 Crown V8
1967 monza 110/4---1968 monza 110/4
1971 amante gt 110/4
CORSA/RMC/PPCC/V8 Registry

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Re: When to rebuild turbo
Posted by: roger65180 ()
Date: June 29, 2020 03:42PM

I also had a compresser wheel explode , if there is any nicks in the wheel I would get it inspected at a turbo shop and rebalenced when they let go it is bad. I have also had dammaged turban wheel that one broke the turban shaft at the compresser and beat the hell out of my eflow wheel

Roger R
Madison Wi
62 ct pg turbo
65intercooled 180 4sp,autocrosser
62 Rampy

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Re: When to rebuild turbo
Posted by: Doug64Vair ()
Date: June 29, 2020 08:06PM

OK, you have convinced me to take it apart. Thanks for all the good input! I'll share what I find with pictures.

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