[Carlos85G]

Hello, everybody.

My exhaust manifold is cracked and also leaking on the head side on my '97 Tracer, so I decided to replace it with a new ATP one. I cleaned as much as I could on the head's surface but, as much as I try, I just can't remove the roughness left by the old metal (Fel-Pro) gasket (I used Spray-a-Gasket on it before installing, so it might have some persistent glue as well). The new manifold comes with a new, classic, graphite gasket but I don't want to go back to this in a few months in case the gasket wasn't enough and have to start all over again, so I decided to go the Ultra-Copper route.

As I was already planning on using Permatex Ultra-Copper RTV for the EGR and its pipe (gaskets are unavailable locally), I'd like to use it on the manifold as well, but I want to be sure on how to do it: should I apply it to both sides of the gasket? Should I apply only on the head side? Should I skip the gasket and use just the sealant? Should I re-use my old metal gasket instead, along with the sealant?

Any help is appreciated.

 

[Joey_Twowagons]

I can't imaging it will seal if you don't get all the old gasket material off, unfortunately.

 

[marclar]

dont use any 'sealant' that stuff will not work in this application, and you will be back in there fixing it in a week. use the graphite gasket and nothing else. there will always be some 'roughness' left from the impressions of the old gasket. as long as there are not physical chunks you will be fine.

 

[Carlos85G]

I'm attaching some pics of how the surface looks right now, after carb cleaner, brake cleaner, degreaser, green Scotch-Brite pads (by hand, no power tools) and plastic scrapers. Would just the graphite gasket be enough, then?

 

[marclar]

that sufrace looks great. honestly much better than most. I would recommend throwing the gasket on and running it. nothing else needed.

 

[Carlos85G]

Installed using only the gasket and I tried several torque sequences. Close, but no cigar. I'll try with Ultra-Copper another day.

I'll post a video of the bubbles later.

 

[marclar]

you have another problem then, perhaps the manifold is warped. you should NEVER need to use rtv on an exhaust gasket. IF it is in fact leaking still, the rtv will simply burn away.

 

[Joey_Twowagons]

Bubbles?
If the leaks are only detectable by bubbles I'm guessing there is no problem. But then I've never checked for exhaust leaks the way I check for tire leaks.

 

[marclar]

ya im sort of confused. not sure i've ever seen anyone use any sort of bubbling liquid to check for leaks. you can typically hear them. maybe the bubbling is from the heat causing evaporation.. not sure

 

[Carlos85G]

What I did was use a vacuum cleaner and set it to blow, then stick the hose through the tailpipe, spray some soapy water on the manifold joint and check for bubbles. This way, I don't have to worry about it getting hot and boiling the water away.

Unfortunately, I haven't been able to upload the MP4 showing the leak. This manifold is new (ATP) and the head has less than a year (EngineTech), so I would be surprised if any of them would be warped.

 

[marclar]

interesting, I've never seen anyone do something like that. always just install and run it. did you start it and see if there were actual exhaust leaks? or just the vac? keep in mind the gasket has a mastic inside that needs to heat cure.

 

[Carlos85G]

I installed everything, torqued to 22 ft/lb (I know, it was too much), then started the car to let the parts heat up and to burn all the protective oil the manifold was covered with (I did clean all mating surfaces with brake cleaner), then I tried the vacuum method and got the bubbles on the passenger side, so I loosened all nuts and re-torqued everything to 16 ft/lb, doing an outward spiral pattern but still the same.

 

[marclar]

well your first mistake was loosening and tightening with less torque, should have just left it. I'm still curious why you did this vacuum pressure test, never have I ever heard anyone of doing that. if it was me, i'd tighten the bolts back down and be done with it.