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Found a crack on wastegate

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Old 07-25-2010, 12:17 PM
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Found a crack on wastegate

Hello,

Il get pics up in the next couple days when i get the turbo back. will be easier to see what im talking about unless anyone knows already what to do

We recently pulled the turbo out of my buddy's car to have it rebuilt and we found a hairline crack on the casing right were the wastegate sits. Its about an inch long, how does this affect the wastegate when it closes? can it be welded?

Its the stock greddy turbo kit.
Old 07-25-2010, 12:36 PM
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ok, its not the greddy turbo but one with basically what im looking at.

Yellow line would be where my crack is at.
Attached Thumbnails Found a crack on wastegate-turbo1.jpg  
Old 07-25-2010, 01:27 PM
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Had an identical problem with the OEM turbo in my RX-7. (See the pic.) Talked with people who know what they are talking about and the concensus was, "don't worry about it". After completing the porting, I reinstalled the turbo and ran it for several months until I had another unit upgraded by BNR.

I was told by an old hand at welding that it is possible to weld cast iron but he did not recommend it. Needed to take the turbo apart to do that and he would not guarantee that it would not crack again. So my advice is to not worry about it. In time, the crack may widen a bit due to the hot exhaust, but that should have only a minor effect on boost levels. Run it 'til it fails at some point in the future and then replace it.

Apparently, cast iron is gonna crack to relieve stress. The crack indicates that the stress in that area has been relieved.
Attached Thumbnails Found a crack on wastegate-wastegate-crack2.jpg  
Old 07-25-2010, 03:37 PM
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ok, thank you i didnt want to get it all back installed and be a big problem.

Would this by any chance cause more back fire then normal? i know obviously tuning is major part in that and we will always have back fire.

its all stock greddy kit and runs no more then 6 or 7 pounds.
Old 07-25-2010, 04:15 PM
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Originally Posted by Z0oMzo0m
Would this by any chance cause more back fire then normal? i know obviously tuning is major part in that and we will always have back fire.

its all stock greddy kit and runs no more then 6 or 7 pounds.
I doubt that a hairline crack in that location would have any effect on "backfire". Yeah, tuning is obviously the key to making sure the A/F Ratios are optimum. If the AFRs are correct, there should be a minimum of unburned fuel in the exhaust to support afterburning.
Old 07-25-2010, 04:18 PM
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Eventually things will break, just the matter of time.

Greddy is NOT known for high quality. just keep that in mind.
Old 07-25-2010, 04:36 PM
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right one, just wondering if anyone else has had this problem from greddy, or even if they know about this happening..

i did some google'ing and seems its pretty common, and most people "ignore that its there" until they start having real problems.
Old 07-25-2010, 08:35 PM
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yup its common. I had an '87 Supra Turbo and it had several cracks around the waste gate opening on the inside like that.

Actually that CT26 even had a large crack down the exhaust side and had a side to side shaft play of at least a few mm (no axial play) and it still pulled strong...
Thinking back I treated that car poorly, but I was ignorant back then. I had no idea you where supposed to let turbo's cool down... haha

I can remember getting off the 401 for gas after a good boot at night and seeing a bright light under my engine bay. I popped the hood to find my exhaust manifold glowing red!
Wow I was dumb... haha
Old 07-31-2010, 12:40 AM
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Yes cas they would say (probable case) that bends the Constitution but they dont want to up held the 2nd the right to bear arms.
Old 07-31-2010, 01:14 AM
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huh ^^^^^ scratches head HAARDDD

explain please..
Old 07-31-2010, 01:22 AM
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yep - got a crack like that - no problem
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