How hot does an exhuast get? A.I.S. Blocking

[BobBrumby]

I am blocking the air injection system down at where the headers bolt onto the heads. I found a circular peice of metal that fits well, namely a 10 cent peice, and wanted to use some 316 degrees CELCIUS red rtv silcon on the thread. Will this this stuff cut the mustard?

[Flowmastered87GL]

I believe that a coin should work... we use 25 cent coins (quarters) up here to block them off.

[jeffast]

like 6-700 degrees i think probably more but i want to be conservitave

[4x4_Welder]

Gas, N/A: 1000ºF

Gas, Turbocharged: 1500ºF intermittant

Diesel, N/A: 850ºF

Diesel, Turbocharged: 1200ºF

 

General guidlines I have picked up over the years.

[BobBrumby]

Sorry for not being more speicific but what temp would the exhuast headers reach?

 

So I supose you dont use any sealent with your quarters? Oh and are your coins made of nickle?

[85Sub4WD]

I blocked the AIS at the head by getting a cheap piece of aluminum, cutting the general shape of the AIS connector out, and drilling two holes in it - guranteed to work, and it is EASY to do - I reused the old gaskets

 

I had the same question about exhaust temperature yesterday - a friend has a laser-thermometer that can tell the temperature of an object you shoot it at - at normal operating temp, the head/exhaust connector read about ~500F MAX, mostly ~450F - realize the block IS aluminum so you won't/shouldn't get too high a temp on it

 

anyway, I used Permatex ultra-copper high-temp RTV silicone sealent rated to 700F (in addition to new y-pipe seals) - have driven 50 miles in it, no problems so far

[GeneralDisorder]

Mig welder, and a flat washer that fits inside the spacer under the head. Just weld it in. and fill the hole in the middle of the washer with weld too. Done.

 

In the case of the EA82 - angle grinder cut the end of the pipe from the head off and do the sale thing - flat washer for fill, and weld it solid. Then re-install your new "block off plate". Easy

 

GD

[Ross]

On some tests we did on a mitsubishi 4g11 at uni, exhaust temps rose to almost 700degC, at full throttle 3000rpm. So, no, silicone wont do. Get some "maniseal" or "Firegum".

[zyewdall]

Gas, N/A: 1000ºF

Gas, Turbocharged: 1500ºF intermittant

Diesel, N/A: 850ºF

Diesel, Turbocharged: 1200ºF

General guidlines I have picked up over the years.

 

Sounds good given my experience (diesels at least). I don't know if the actual manifold gets at hot as the exhaust gasses though. I like the idea of MIG welding it on. Or using fireplace/exhaust cement or something, but that's usually too brittle and vibrates out. Heck, try the RTV silicon, and if it fails, you'll at least know.

 

Z

[BoostedBalls]

I'm a little bit lost here, are we talking about an ea-82t engine? Are we talking about the stainless EGR tube? I know that is threaded into the head near the exhaust port. We must be talking about the non-turbo ea-82 because I don't have anything like you guys are discribing on my ea-82t.

 

I have used the red rtv on exhaust gaskets before when I was in a pinch and it held up fine in a n/a big block chevy. It was on a jetboat with wet headers so there wasn't any exhaust backpressure, not sure how it would hold up under these conditions.