HKS 1.8 Cast Turbo Manifold Plug question
 

On the now discontinued HKS 1.8 manifold there is a threaded hole on the bottom of it which I'm guessing was to hook up the EGR. I bought this manifold used from here, and it came with a plug. I was just driving around today and the plug fell out, causing a crazy amount of exhaust to come pouring out of the manifold and into the engine bay. I found the plug on the road, and the threads are totally screwed on the plug (it's the wrong plug). Does anyone have any idea what thread type/bolt size this hole is? I'd rather not have to take my manifold out. I put the old plug back in and it'll probably last a day...

Well since you don't have an answer yet, my first guess would be 1/8NPT...that's what size my EGR probe and hole for it in my Begi manifold is...you'll probably only find it in brass at an auto parts store-I got one at PepBoys

Thanks for the reply. It's actually a very big hole (larger then the screw on portion of the connection EGT rod). I'm guessing it originally came with a piece that screwed in and gave you a 1/8NPT fitting on it. I'm going to call HKS this morning and see what they say.

Well you could measure it and get a ballpark then go to a hardware store and look at their NPT pipe plugs and see how they fit. If it's tapped in a pipe thread size you should be able to get pretty close with 1/4", 3/8", 1/2", 3/4" inch-those are common sizes. They probably also have reducers you can use to plug the EGT into if needed.

Well HKS was totally useless. The lady on the phone said it was a factory replacement part, and they don't have any specs on it.... yah ok. So I think I'll go the route scotty suggested and just get a general measurement, and just pick up a bunch of bolts. There are very few threads in it so I can't really get a proper feeler gauge.

EGR, not EGT.

One thing you might try to aid the plug in fitting (assuming there may be some damage to the threads in the manifold) would be to go to the auto parts store and pick up a tube of muffler patching putty. I have no idea how well it'll hold up on an exhaust manifold as compared to a muffler, but it's gotta be better than nothing, and since you're essentially just using it as a thread sealer / locker, I'd wager it might have a fighting chance.

Hmm that's a good suggestion. I was thinking about slathering some JB Weld on the threads, and putting the plug in. Not sure how well it handles temperature though. This would be a lot easier if the turbo wasn't on the car, and I just put it on so I don't really want to take it off.

By the way, thanks everyone for posting ideas.

I don't think jb weld will work. It softens with the heat and stinks up your whole car. Ask how I know :laugh:

Permatex sells a metal repair kit that may work though.

^^ lol i remember that happeing lol..yep jus like sprayed said jb softns up and eventually itll crack..happend to me once

go to ur local muffler shop see if they have anything..worth a try

green loctite on a brass plug. shouldnt go anywhere.


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