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Ben2045
03-28-2011, 07:33 AM
I'm hoping you guys who are oh-so much more knowledgeable than I am about the 3g's can give me some insight.

I've got an 89 Accord LX-i that I've been working on for a few months now. It's completely stock, no mods or upgrades at all. I had to get a new car for a longer commute so I decided to put this on the "project" list, taking the engine apart and replacing gaskets/seals/rings, etc. The only issue i've run into is with the exhaust manifold.

I replaced the gasket (the old one fell apart when I got it off, so about time), got the manifold and heat shield back on, EGR pipe re-attached, and started it back up. It works just rgeat for a few minutes, then smoke starts pouring out from around the mating surfaces. As near as I can tell there isn't anything underneath the manifold to leak onto the downpipe, and I know for sure there isn't anything leaking onto the top. I thought it might just be cleaning chemicals burning off, but it's not lessening as I let it run more.

Any ideas from you guys would be welcome, as this is the last bit I need to finish before I can drive it around again.

Xaisk
03-28-2011, 10:05 AM
Sounds like youve been doing some hard work on the car. The exhaust manifold gasket is easy. If it leaks after putting the new one on then you need to take it off and use a metal file to file the surface on the manifold itself flat and smooth, then on the block where it meets the manifold. Check the gasket for cracks or problems since youve ran it and it probally had time to mate and then took it off. If it checks out then put it back on with some gasket sealant. That should stop it from leaking. They generally leak if they are old. Things tend to warp, or a small chip in the block or manifold need to be filed down or a leak.

Good luck.

Ben2045
03-28-2011, 10:11 AM
You could say hard work, or maybe just time consuming. I managed to remove the intake manifold and replace the gaskets that go with it, all without taking the head off. Not something I'm interested in doing again though, as I think I invented several new profanities trying to get to the bottom nuts.

Taking it back off and filing will have to wait till this weekend, but what kind of gasket sealant is used on exhaust manifolds? I was under the impression that the exhaust side didn't need and sealant, is there a particular high temp type to use?

Xaisk
03-28-2011, 12:12 PM
I dont remember what stuff I used... It came in an aluminum tube.. I think it was Mr. Gasket or something. Its not NESSECARY to use the gasket sealant, but a thin layer evenly spread across the manifold cant hurt either. Just make sure it is as flat as you can get it.

I did mine like that and I dont have any leaks.

Dr_Snooz
03-28-2011, 05:27 PM
This is curious. Generally, if you have an exhaust leak, you don't see it, you hear it. It would be unusual for it to smoke, especially if you aren't also blowing smoke from the tailpipe. Are you absolutely certain that nothing is dripping onto it? Where did you get the gasket? Are you sure it isn't burning?

Ben2045
04-05-2011, 09:24 AM
I'm completely positive there's nothing dripping on it. I changed the valve cover gasket and dizzy o-ring, which are just about the only things above it, and there aren't any lines or anything running underneath to cause it.

It's the Felpro exhaust manifold gasket, and it fits just like the previous one. I think it may have to do with some of the bolts/nuts holding it on. I'm not sure WHAT the previous owner did, but there are an assortment of different shaped bolts for some of the mounting pieces, and the other ones are studs with nuts on, some double stacked, some with single nuts, and one stud that looks like part of it was broken off.

Looking forward to tackling this one, I hope at least I can get the sun to shine on Seattle for a few hours this weekend.

P.S. I can definitely hear the leak, but I think what's happening is one or more of the bolt holes is stripped and the bolt isn't pulling the mating surfaces together, creating a big enough leak for the exhaust to spill out.

Hail Doom
04-05-2011, 06:23 PM
I generally use copper gasket paint on the exhaust side. I recently replaced all of my exhaust manifold mounting hardware (studs, spacers, nuts) for about $45 through the local dealer, but you could probably find all of that stuff in decent shape at a junkyard for much less than that. It helps to put everything together as per the shop manual. (http://www.pauldesign.ru/honda/shopmanual.html)

Dr_Snooz
04-06-2011, 08:39 AM
Vid of smoke please. Also, you're saying that smoke only comes out between the block and the manifold, but not out the tailpipe, right?

Xaisk
04-06-2011, 10:12 AM
I would remove the studs from the block and put new ones in with a set of fresh bolts. That is friggen ridiculous.. non matching bolts and torn studs?

previous owner FTL