Exhaust leak after Berk HFC & F.I cbe install

[apatter8]

I need some help guys. I installed my new F.I. exhaust and used Berk HFCs today, and I've got a leak at the HFC-to-exhaust manifold connection on the passenger side. I used Fast Intentions 3-bolt gaskets for this connection. It's a fairly significant leak (can feel it through gloves), and tightening the bolts further did not help. I'm waiting for it to cool back down now, what are some things I could try? Maybe loosen it up and make sure the gaskets are aligned? I don't remember there being much slack there, but I can at least try it. Any other ideas?

[SS_Firehawk]

Those Z1 gaskets seem to do the trick if you can't get the F.I. gaskets to work.

[DEpointfive0]

The Z1 gaskets are perfect

[MJB]

I've seen the flanges on brand new HFC's and TP's warped before... might be something to consider. Whenever I get a new exhaust or HFC/TP, i a put a straight edge like a ruler or something against the flange to make sure everything is kosher.

[apatter8]

Z1 gaskets may be the solution then. I may have unevenly torqued the bolts on the passenger side, due to the top one being so hard to get to. I normally tighten in increments, but since the top bolt is so hard to get to I tightened it all at once.

[F.I. Inc.]

Originally Posted by apatter8

Z1 gaskets may be the solution then. I may have unevenly torqued the bolts on the passenger side, due to the top one being so hard to get to. I normally tighten in increments, but since the top bolt is so hard to get to I tightened it all at once.

There is nothing wrong with the gaskets I sent you. I have been using them for 6 months now and just got finished doing extensive dyno testing on a twin turbo car with them last week. No leaks at all.

1) Make sure that you DID NOT use the stock metal crush ring from the stock catalytic converters.

2) Make sure the two mating surfaces are clean.

3) The bolt holes on our gaskets are slightly over sized to the stock studs and bolts so our hardware can fit through it. When you tighten everything down make sure the gaskets are not cocked one way or another and that any excess that might peek out between the two flanges is even all the way around.

4) Last but not least, no dig at the Berks but make sure the flanges are not warped.

If you have any questions at all, please do not hesitate to call me directly at the shop.

Thanks, Tony

[apatter8]

Originally Posted by F.I. Inc.

There is nothing wrong with the gaskets I sent you. I have been using them for 6 months now and just got finished doing extensive dyno testing on a twin turbo car with them last week. No leaks at all.

1) Make sure that you DID NOT use the stock metal crush ring from the stock catalytic converters.

2) Make sure the two mating surfaces are clean.

3) The bolt holes on our gaskets are slightly over sized to the stock studs and bolts so our hardware can fit through it. When you tighten everything down make sure the gaskets are not cocked one way or another and that any excess that might peek out between the two flanges is even all the way around.

4) Last but not least, no dig at the Berks but make sure the flanges are not warped.

If you have any questions at all, please do not hesitate to call me directly at the shop.

Thanks, Tony

Thanks for the reply Tony. I thought about calling you, but it was late on a Sunday and I didn't want to bother you. My thinking in using the Z1 gaskets was that their added thickness may compensate for any warped flanges. I'll check the things you mentioned tomorrow, and I may give you a call.

[MJB]

This picture was posted by mleroux in the 350z forum. I won't mention what HFC's these are, but I know the company acknowledged the problem. Like I mentioned before, I always check the flanges on any new TP or HFC to make sure they are straight. If the gaskets aren't effective, than I would pull the cat off and check.

I've had flanges on a pair of TP's once that were alot worse than in the picture. I won't mention the company, but I sent them back and got another pair.

[apatter8]

I didn't check the HFC flanges before installing, shame on me I guess. And since one stud is reused from the exhaust manifold connection, I'll have to practically disassemble everything just to get the cats off, right? Today is going to suck.

[apatter8]

Alright, I got the cat off and some pics:





When set on the countertop, you can see the flange is not perfectly flat. Is this enough to cause my leak? Can an exhaust shop straighten this out for me?

[apatter8]

Got it fixed at a local machine shop. Everything's good now, just hope I didn't screw up the recommended break in of the exhaust while I was checking for leaks.

[F.I. Inc.]

Originally Posted by apatter8

Got it fixed at a local machine shop. Everything's good now, just hope I didn't screw up the recommended break in of the exhaust while I was checking for leaks.

Great talking with you yesterday. I am glad that it worked out for you.

See, I told you it was not our gaskets.

Thanks, Tony