Turbo Gone Bad?

[morepowr]

Right now at this moment unfortunently I own a 81 turbo Reagal. (I'M ON A "GENERIC" BEER BUDGET)How do u tell if your TURBO'S bad.No smoke,no vacume leaks,boost gauge is hooked up right.But under full throttle, no boost shows on gauge,just vacume up to 0hg's then just stays there at 0hg's until I get off the throttle.So I took off the Exhaust Elbow(what a bitch on the car!) to check the Exh Bypass and it's working fine.I then checked the turbine shaft end play and I can move it a little but how much is bad?I turned the car on while the elbow's off and the turbine spins quick.So what gives?How do I then tell while driving full throttle if my car's even Boosting when It doesn't show it on the gauge??HELP!!!!!!!!!!!!!!!!!!!!!!!!!! P.S. Secondaries are working.Just had carb rebuilt.

 

[turbo2nr]

I think your turbo is fine. It is junk when your car blows out oil like a crop duster, or the wheels in your turbo are hitting the housings. A factory turbo can last a long time if treated right, like over 200k miles. You may just have a bad exaust leak, or a problem with wastegate valve (puck), Or other simple prob.

 

[morepowr]

No exhaust leak.Wastegte works fine.When the Exhaust Bypass Valve is open does that bleed Boost out or let Boost in?Duh???

 

[turbo2nr]

I do not know about the systems in a carb turbo Buick, but you have some problem other than the turbo. That car has a carb before the turbo, right? when you say exaust bypass, are you refering to the hole in the back of turbo that a round disk covers up? Check that area for binding, the disk (puck) must cover the wastegate hole all the way untill max boost is reached, then it opens to bleed of extra exaust pressure, and stop the turbine wheel in turbo from accelerating any more, creating an over boost. An exaust leak may be hard to hear or see untill car has a lot of exaust pressure, and load on the engine. You can't just pop the hood and rev motor up in neutral. This sounds like the symptoms of an exaust leak or a leaking/ broken waste gate system. You should have a rod attached to exaust near back of turbo, disconnect that rod and try to move arm on exaust. Is it stuck?

Scott

 

[morepowr]

No the rod is not stuck.With the arm unattatched it retracks under vacume and when throttle is added it moves outward to close the Bypass(Hole) in the Exhaust elbow.I even disconected the WasteGt/Arm and wired the Exh Byp flapper clsed to shut the Hole up and still no Boost reading?This is the only year (81) that this turbo setup is a normally closed system(Wastegate).All the other years were Opened.There is no Exhaust leak,I GUARANTEE IT! Also the puck moves (open and closes fine).

 

[turbo2nr]

Well sorry i can't help you. Your turbo is fine I think. If it is on your car and can turn at all, it should make boost. There is not much to a turbo. It just spins! You sound like a fart smeller, I mean a smart fella, so I think a little more time, and poking around, and you will figure it out. I have no idea what you ment when you said your car was the only year to have a normaly closed bypass system. What are you talking about? A bypass valve is also known as a Blow off valve, or a sneeze valve. It releases boost when throttle plate is closed, like on stick shift import cars, to keep up rpm of turbo during a shift. It is not used to regulate the exaust pressure before the turbo. A bypass valve can also be used to bleed off extra boost from a centrifugal supercharger because of non linear boost compared to a roots or lysholm blower where boost is directly related to engine rpm.

Scott

 

[morepowr]

I'm sorry I think I read it wrong.I read in "B4BLACK" that the (Waste gate Actuator) normally is a closed design.But in only 81' they made it an open design to in increase fuel economy.But because of poor performance issues that they had changed back in 82' to the closed design.I had thought that it may have a part in my problem?And your right if it spins,it should have boost.Could there be a vacume leak small enough to mess the gauge up but not notice it on the car?How much Turbine Shaft play is the minimum?The ends of the Turbine Blades on the Exhaust side look a little worn ,so maybe at one time something got SUCKED up and hit the blades?All I know is every thing seems to run Great and is hooked up the way it should be but still I'm floored doing 60mph and no boost reading.I have no idea WTF is up!Thanx for yor input and your help.

 

[turbo2nr]

Well, if the wastegate is open, you will get no boost. How is it going to close for boost, then open again for controling the over boost? Check your accuator. Pull off the line going to the round accuator and blow air in line(s). You may have a closed area on both sides of the diaphram. No air should pass through at all. Should be a sealed area. Blown diaphram? My turbo Rivieria has a port on both sides of accuator. Is yours hooked up correct? My 87GN is different.

Scott

 

[morepowr]

I only have one port.No leaking it works fine.I think just a bad gauge maybe.Oh well ,I'll keep trying to figure it out.thanx..