1989 Turbo Wastegate

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TN Aero
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Joined: Sun Feb 11, 2018 3:38 pm

1989 Turbo Wastegate

Post by TN Aero » Mon May 14, 2018 1:46 pm

I am still rebuilding 1989 #46. Before putting everything back together, I decided to test the wastegate function and put 10 PSI gauge on the port normally connecting to the manifold. Air leaked out around the actuator. Charlie at evergreen turbo tells me that it should hold pressure and not leak. He says the internal diaphragm must be cracked. Does anyone know of a place to get a replacement diaphragm (or two)? The actuator is free to move and when I do put 10PSI on it, it takes less force to move it. Does anyone know if the diaphragm is flat (I can make a new one if it is flat), or cup shaped? I have not had an opportunity to disassemble the actuator - wish I had instructions and know that I need to be careful with the springs under force. If testing to set the wastegate actuation to the correct absolute manifold pressure what should my input PSI be - Charlie says it should be more than 10 he normally expects the actuator to be fully "open" at 18-20PSI. Any help advice is appreciated.

avcwo
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Re: 1989 Turbo Wastegate

Post by avcwo » Tue May 15, 2018 3:05 pm

Contact Reed Patridge at:
http://www.workturbochargers.com

He will answer all questions. He can also machine your original housings to hold modern cartridges....BIG improvements in reliability (ball bearing vs. Journal bearings.). Expect greater compression out of the same size package due to modern turbo internal component improvements.
AVCWO
1987 CTTC #9 of 184
GEAUX NAVY!!
GEAUX LSU TIGERS!!

TN Aero
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Joined: Sun Feb 11, 2018 3:38 pm

Re: 1989 Turbo Wastegate

Post by TN Aero » Tue May 15, 2018 4:18 pm

Thanks AVCWO. I already had new bearings machined for the turbos and then sent them to be rebuilt by Evergreen Turbo in FL. I decided to test the wastegates - I did not send them to Evergreen and they leak. I wish I had known about this before, because ball bearings vs journal would be a great improvement, but I don't want to go back again. Hopefully they can help me with the wastegates though.

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SurfnSun
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Re: 1989 Turbo Wastegate

Post by SurfnSun » Tue May 15, 2018 9:43 pm

Did you call Callaway about watergate diaphragms? They are super easy to rebuild.

TN Aero
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Re: 1989 Turbo Wastegate

Post by TN Aero » Wed May 16, 2018 1:04 pm

SurfnSun - I did not. I will though. I did not see these in their online store. Thank you very much. I assumed they were not hard to rebuild just needed the right material.

TN Aero
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Re: 1989 Turbo Wastegate

Post by TN Aero » Mon May 21, 2018 4:00 pm

Callaway will not sell me the parts (diaphragms). They will only let me send the wastegates to them and they will rebuild them. I think I am going to take mine apart and see how they are constructed and see if I can make my own diaphragms out of a sheet of Viton rubber.

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SurfnSun
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Re: 1989 Turbo Wastegate

Post by SurfnSun » Mon May 21, 2018 9:08 pm

How much are they charging?

TN Aero
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Re: 1989 Turbo Wastegate

Post by TN Aero » Mon May 21, 2018 9:55 pm

$175 per wastegate plus shipping and taxes

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