Had to drop the y-pipe on my '99 Legacy Brighton (2.2) in order to lift the motor in order to change the oil pan (fun!).
And of course in the process of removing the nuts from the exhaust flange studs, 3 of the 4 studs came out and stripped the threads in the aluminum motor. More fun! Got some Helicoils which should take of that.
I'm going to take a shot at reinstalling my factory y-pipe--flanges are rusted, but it was OK before and the rest of it is reasonably solid. Got new OEM gaskets and studs/nuts. Question is, would any sort of RTV or sealant be advisable on those gaskets? I'm thinking not, but on the other hand given the sketchy condition of the flanges (and the surface on motor that mates with the flange is not perfect either), perhaps some judicious use of high-temp. RTV (sensor-safe type) might be in order.
Any feedback or advice welcome.
By the way, when threading in the exhaust studs, should they just go in dry? Or should I apply something to the threads? I am going to antiseize the heck out of the threads where the nuts thread on, of course.
Thanks. Wish me luck. I will try and post pictures.
Got the helicoils installed--first time. On two of them, the threads I tapped were'nt quite deep enough so part of the helicoil is slightly above the hole. What's the best way to trim these?
Was my first time tapping threads also, used oil but it was awkward, not room for the tap handle on 3 of the 4. Had to use pliers and vice grips.
When tapping, do you want to back the tap out periodically? Or just back a partial turn frequently as you go deeper? Seemed to work OK but I pretty much just went straight in (with lots of oil and careful turning), later saw online how you should back the tap to clear chips. Just wondering about the correct method for next time.
Gaskets should arrive tomorrow, hopefully can finish the job. Appreciate any advice pertaining to questions in my original post.
I gave it a try with some wire cutters but didn't really do the job. I'll see if I can locate a dremel tool of some sort. I chased the threads on the inserts, but where the coils protruded above the hole it was hard to start the thread chaser tool. Probably best to trim them down.