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Discussion Starter · #1 ·
 Hi
 I have no knowledge of Turbos and need some advice on the state of turbo in my 82’ZXT.
 My boost gauge registers no boost, never goes past 0.
 Car idles nicely, but will backfire under hard acceleration, has power but lacks quickness.
 So I think maybe the Turbo has frozen up. Am I right?
 Also , is it true that the by-pass valve can be moved back and forth freely with just the touch of the hand?
Mine (by-pass valve) doesn’t move it all. Is it stuck? Would it be ok to may be jarr it loose by tapping on it ? Or would I ruin it by doing that? Or is the Turbo already shot?
Any advice would be greatly appreciated..
tom
 

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Discussion Starter · #2 ·
Hi

The stock gauge is highly inaccurate, I would try hooking up a aftermarket gauge to see how much boost you really are getting. I know on my Z the factory gauge was going right to the red line but when I hooked up another boost gauge I was only getting around 4 lbs of boost.

My turbo seems to have the same problem yours does. My wastegate lever (on the turbo) seemed to be frozen also. Every other Z I have messed with I have been able to move the lever by hand, on my 83 I cannot.

If the lever is not moving at all, and frozen in a open position, (like bent back towards the firewall) it is probably partially open and that is why you are producing little or no boost. I took a open end wrench, not sure the exact size but I can look if you'd like, that fit square on the end of the lever (disconnect the wastegate arm) and soaked it down with some liquid wrench, and broke it loose that way. Work it back and forth a few times and see if you can loosen it up that way.

Pay attention to the position of the lever before you start, if you are able to move it to the left (Towards the wastegate) then it was indeed partially open and you were losing boost that way.

I'm sure that the lever being that tight indicates something is internally wrong, but doesn't mean you cannot build boost with this turbo. I can build 13 or 14 lbs with my turbo in this condition , it is just a little harder to regulate.

sorry so long
 

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Discussion Starter · #3 ·
Dave83ZXT Re: Defective Turbo Question

> Hi

> The stock gauge is highly inaccurate, I
> would try hooking up a aftermarket gauge to
> see how much boost you really are getting. I
> know on my Z the factory gauge was going
> right to the red line but when I hooked up
> another boost gauge I was only getting
> around 4 lbs of boost.

> My turbo seems to have the same problem
> yours does. My wastegate lever (on the
> turbo) seemed to be frozen also. Every other
> Z I have messed with I have been able to
> move the lever by hand, on my 83 I cannot.

> If the lever is not moving at all, and
> frozen in a open position, (like bent back
> towards the firewall) it is probably
> partially open and that is why you are
> producing little or no boost. I took a open
> end wrench, not sure the exact size but I
> can look if you'd like, that fit square on
> the end of the lever (disconnect the
> wastegate arm) and soaked it down with some
> liquid wrench, and broke it loose that way.
> Work it back and forth a few times and see
> if you can loosen it up that way.

> Pay attention to the position of the lever
> before you start, if you are able to move it
> to the left (Towards the wastegate) then it
> was indeed partially open and you were
> losing boost that way.

> I'm sure that the lever being that tight
> indicates something is internally wrong, but
> doesn't mean you cannot build boost with
> this turbo. I can build 13 or 14 lbs with my
> turbo in this condition , it is just a
> little harder to regulate.

> sorry so long

+++++++++++++++++++++++++++++++++++++++++++++++++
Thanks for the reply
Is it still possible for the turbo to be physically be frozen in one spot? Possibly due to a clogged oil line or something? Is it possible to remove the oil feed line from both the engine and the turbo?
Hope not too many questions.
Thanks
Tom
 

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Discussion Starter · #4 ·
Re: Dave83ZXT Re: Defective Turbo Question

>
> +++++++++++++++++++++++++++++++++++++++++++++++++
> Thanks for the reply
> Is it still possible for the turbo to be
> physically be frozen in one spot? Possibly
> due to a clogged oil line or something? Is
> it possible to remove the oil feed line from
> both the engine and the turbo?
> Hope not too many questions.
> Thanks
> Tom

Sorry, not sure about your first question. I would try to manually move the lever, towards the wastegate, and see if that helps.
The oil line is easily removed from both the turbo and engine, just have to have patience snaking it out of the engine compartment. Not a bad idea, if you take it off you should be able to tell if it is clogged up or not. I pulled mine off a few months ago just to clean it, and it had a little build up in it.

If your line was completly clogged up and the turbo was not getting any oil, I would have thouht it would be making some unsettling noises though.
 

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Discussion Starter · #5 ·
Re: Dave83ZXT Re: Defective Turbo Question

>
> +++++++++++++++++++++++++++++++++++++++++++++++++
> Thanks for the reply
> Is it still possible for the turbo to be
> physically be frozen in one spot?

If your turbo was completely frozen then the engine most likely wouldn't run at all, because the impeller(part of turbo driven by exhaust) would block the exhaust and your engine wouldn't be able to fire because all the exhaust would remain in the engine(and also slow the engine down on the exhaust and compression strokes).

Project#2501
 
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