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-   -   Permatex Ultra Copper use (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/permatex-ultra-copper-use-1089192/)

blackball7 09-06-15 12:13 PM

Permatex Ultra Copper use
 
I recently had the unfortunate luck of having both of the bolts that holds the plate over the turbo waste gate break off, inside of the holes with no threads showing.... Fun stuff, right?

I don't currently have, or have access to, the tools to remove them nor the cash to have someone do it for me.

I am trying to decide if I should use some Permatex Ultra Copper around the entire plate or if I should just leave it alone.

I figure between the Ultra Copper and the down pipe being connected it should hold it pretty well. I'm just not sure if it would burn up there, being on the hot side of the turbo and all. If it were to burn up then it would be sure to leak! (and a pain to clean up later)

That area didn't have a gasket on it in the first place, so maybe it would be ok without anything, at least while I'm breaking in the new motor and clutch.

I would like to hear some informed opinions on this please, what do you guys think?

(Permatex Ultra Copper is rated for intermittent 700F temps)
(The spray on stuff is only rated at 500F)

barkz 09-06-15 01:20 PM

Plate over the wastegate? Or the plate that is attached to the wastegate actuator? That bolts it to the turbo?

blackball7 09-06-15 01:23 PM

the plate you have to take off to get to the waste gate. Goes between turbo and down pipe

RotaryEvolution 09-06-15 01:34 PM

1 broken bolt would probably be ok, 2 broken bolts is an issue.

even cast iron can warp in time with enough heat.

the silicone high temp sealant is worthless. the spray on copper works ok if you layer it on well enough but it's a sealing aid for properly mounted and tightened down parts. i use the copper spray gasket maker on all the turbo gaskets and have for years.

blackball7 09-06-15 01:37 PM

I'm aware it's an issues. I'm trying to decide how much of an issue

RotaryEvolution 09-06-15 01:39 PM

you can get by temporarily but i would avoid boosting the car hard until you can fix it properly or locate a spare backing plate for when that one does warp.

blackball7 09-06-15 01:43 PM

The next 2500+ miles are going to be break in, so I have some time to find a solution before it gets any hard use.

lduley 09-06-15 02:43 PM

Permatex Ultra Copper use
 
I wouldn't be hopeful of it holding up for that many miles

blackball7 09-06-15 08:28 PM

Apparently I shouldn't be hopeful for an informed opinion either, huh?

lduley 09-06-15 08:39 PM

Permatex Ultra Copper use
 
You've gotten informed opinions, your dealing with something that is hot AND under pressure, both of which don't mix with RTV unless it is squished between something

The most informed opinion you should consider is save some cash and fix it properly without putting a band aid on it and hope it doesn't burst your newly rebuilt engine into flames and costing you even more than what its cost you so far to rebuild it

blackball7 09-06-15 08:47 PM


Originally Posted by blackball7 (Post 11964920)
the plate you have to take off to get to the waste gate. Goes between turbo and down pipe

How is it that the RTV would not be between something? I really don't think you read the post right. Who the hell uses RTV without it being between something? Cosmetic RTV? :lol:

barkz 09-06-15 09:30 PM


Originally Posted by blackball7 (Post 11965066)
Apparently I shouldn't be hopeful for an informed opinion either, huh?

An informed opinion is to fix it correctly, not half ass it, then come here in two weeks with a "think I broke something" thread....

blackball7 09-06-15 11:00 PM

If I were to break something I could certainly fix it without making a thread.

I'm looking for someone that has experience with Ultra Copper and their informed opinion on using it DIRECTLY on the turbo. (Or anywhere near the turbo for that matter)

Saying fix it right or GTFO is only cluttering up what could be a useful thread on how well Ultra Copper performs with the heat of a turbo'd rotary engine. (There is not one out there, go ahead, search.)

This is not some super car with 1000+ HP ZOMG SUPER FAST!!!11! It's an S4 with a mild street port, rebuilt motor (still out of the car), ported waste gate, RB down pipe, and removed emissions. THIS IS NOT MEANT TO BE A PERMANENT FIX. This is to get the car together and start the break in process. Let me repeat this so I know you have read it, BREAK IN. I'm not going to the track, I'm not going out to be super dorifto master-san, and I won't even be boosting for 2500+ miles.

I hope to find an S5 Turbo and manifold before the break in process is complete, but we'll see how that goes...

To Lyger: Thank you for not being like these jackasses with their useless comments. Unless I hear from some people with experience using RTV around the turbo, I probably will just leave it and not chance the leak from burnt out RTV.

To those looking for actual information: The bolts that hold this plate down are subjected to quite a lot of heat, over time this heat softens the metal allowing this to happen. My advice to those taking these bolts out; DO IT SLOWLY. I believe it was my haste to remove them that weakened them enough to snap. Make a small turn on one then the other, back and forth until they come out. It's the heat and pressure that is applied when turning that makes them snap. If you give them time to cool down as you take them out, this hopefully will not happen to you.

I had thought about a couple small tack welds on the edge that is missing bolts (once the down pipe is connected to keep everything straight) but, if that were to mar the mating surface it could be even harder to get it to seal once it was fixed correctly. I won't be attempting that, though in some situations it could be pertinent to weld that plate on.

RotaryEvolution 09-07-15 09:16 AM

i just gave you an informed opinion which is not to waste your money on any form of RTV for the turbo, because it will last all of 2 seconds(yes i have tried it). spray on copper works kinda but even on properly torqued mating surfaces you can see the sealant slowly disappear after a couple years of use.

Aaron Cake 09-07-15 09:25 AM

And I'll second that opinion. I have friend who insist on using "high temp" RTV on their turbo related gaskets and it lasts minutes once the engine had started. The worst part is that it encourages leaks, as the voids which were once filled with RTV that the gasket could not take up, are now well, voids.

Nothing off the shelf at the auto parts store is going work with or in place of the turbo related gaskets.

j9fd3s 09-07-15 09:28 AM


Originally Posted by blackball7 (Post 11964879)
(Permatex Ultra Copper is rated for intermittent 700F temps)
(The spray on stuff is only rated at 500F)

EGT at idle is around 700F, and then it peaks around 1350F with a stock ecu. obviously exhaust gas temp =/= turbo temp, but still based on that, life of any silicon/spray on gasket will be short

RotaryEvolution 09-07-15 09:31 AM

the copper generally remains on the parts as a sealing aid from the spray on material, after the liquid portion of the gasket maker has baked off.

the silicone can't even take 700F because the backpressure in exhaust is the deal breaker that pushes it out.

KompressorLOgic 09-11-15 12:19 AM

ive seem to have good results with a very thin layer of ultra copper when reusing exhaust gaskets for like the catback, or midpipe, I don't think it would help at all for something that close to the engine esp with no bolts on that portion there....

I would look into taking the turbocharger off and drilling the studs out and somehow rethreading them.

KompressorLOgic 09-11-15 12:23 AM

hmm ok reading more into it I see you cannot afford to fix it properly,

I would just try running it like it is? and see how bad the exhaust leak is.. if its minor its proably not too big of a deal in the short term.

blackball7 09-13-15 01:18 PM


Originally Posted by Lyger (Post 11965222)
i just gave you an informed opinion which is not to waste your money on any form of RTV for the turbo, because it will last all of 2 seconds(yes i have tried it). spray on copper works kinda but even on properly torqued mating surfaces you can see the sealant slowly disappear after a couple years of use.

I see that now. Probably missed it between all the snot coming out of my nose and hacking up the rest... :icon_tdow


Originally Posted by Lyger (Post 11965235)
the copper generally remains on the parts as a sealing aid from the spray on material, after the liquid portion of the gasket maker has baked off.

the silicone can't even take 700F because the backpressure in exhaust is the deal breaker that pushes it out.

So there's actually copper in the spray stuff? Kind of interesting and unexpected.


Originally Posted by KompressorLOgic (Post 11966861)
hmm ok reading more into it I see you cannot afford to fix it properly,

I would just try running it like it is? and see how bad the exhaust leak is.. if its minor its proably not too big of a deal in the short term.

I don't have the proper tools to fix it myself. After talking to some friends, and really not wanting to take the turbo off later, I found a place that fixed it for less than both arms and a leg!

I was looking through some pictures I took before I tore it apart and I'm not positive if there is supposed to be a gasket there or not. The last owner changed all the exhaust gaskets near the engine and replaced them with those shitty paper like ones and they were torn, blown out, and just completely fuckered up before I got it. He didn't even put 1000 miles on the car. (A lesson for all those that are thinking about going the cheap way for those gaskets)

So, does anyone know if there is supposed to be a gasket there? Or is it just iron to iron?

Oh, and thank you for keeping the posts helpful guys! :nod:

blackball7 09-13-15 01:36 PM

Just thought of something else. What do you guys use to lock the header nuts down? Those three pieces of metal that were welded together broke and wasn't working anyway. Regular lock washers might work, but I'd rather have something like castle nuts and safety wire. Thoughts?

j9fd3s 09-13-15 03:39 PM


Originally Posted by blackball7 (Post 11967681)
Just thought of something else. What do you guys use to lock the header nuts down? Those three pieces of metal that were welded together broke and wasn't working anyway. Regular lock washers might work, but I'd rather have something like castle nuts and safety wire. Thoughts?

the FC uses normal nuts with a lock tab thing, which is hard to use.

the FD and everything after that uses a flanged nut with a little section on top that is crushed so it locks. these do work great, once a thing is together, its together. the problem is that if it needs to come apart later, they like to eat the threads. the Mazda nuts are inconel, and very expensive. Kia has the same nuts but in something softer. and BMW has something similar in copper, which is easier on the threads.

RotaryEvolution 09-13-15 03:46 PM

copper nuts don't really work on the turbo, you can use standard metric nuts with lockwashers. the inconels are the best but not absolutely necessary.

erick31876 09-13-15 03:49 PM

I think I might have a spare plate laying around, but it's from a s4 turbo, not sure if they are the same. You can have it if it will work, I also have a hot side. That has some cracks on the inside of it, but all of the bolts and or studs are good that you are welcome to as well if you want to pay for the shipping

blackball7 09-13-15 04:48 PM

I don't need parts. The bolts were extracted and the holes helicoiled. Is there supposed to be a gasket under that plate that goes over the waste gate?


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