Auto Transmission Lower engine to transaxle bolt

[sierraxr7]

I just bought a 90 Mitsubishi Eclipse. They replaced the motor with one of those 30K mile Japanese motors. When I drove it home it ran beautiful then suddenly started making a noise in the lower engine compartment. Checked it out and discovered the transaxle bolts were only hand tight and lower engine to transaxle bolt was missing. I need to find out the bolt deminsions i.e. thread size, diameter, and length. I need this info quick, Anyone. Thanks.

[gthompson97]

I think it's like a 17 or 18mm socket that fits on it, but that's all I know. Just pull a different one out and get one exactly like it.

[sierraxr7]

I wish it were that easy. I think I got a raw deal. The block is threaded and the transaxle is threaded something ain't jiven here. Looks like we are going to have to drill out the block so we can get the Transaxle to tighten up flush. Anyone run into a situation like this?

[gthompson97]

Are you sure the block is threaded? It could just be "marks" from the threads when the bolt passes through it, but that's just a guess. Either way, if the holes are the same size, it doesn't hurt to have the block threaded too, just takes a little longer to put the bolt in.

[Blackcrow64]

Wait... I think the block is supposed to be threaded and the tranny holes drilled out... I had a problem with one of mine being screwed up like that too.

[sierraxr7]

There is no way the transaxle will thread up to the block if the block is threaded, at least that is what I am being told. There is a possibility that the block could be marked up from bolts passing through. I ask the guy before I bought the car if there were any other known problems besides needing a computer and passenger window. He said no. So I am wondering why after getting the car almost home it starts make noise near the bottom of the engine. We raised the car up to check it out and found all the transmission bolts were barely hand tight, the bolt in question is missing and there is a pretty good size gap between the tranaxle and block. Also had a nut missing off the motor mount. Thought it would be an easy fix, not!

[sierraxr7]

The tranny hole would have to be drilled all the way through so that a nut could tighten it up and keep it secure. Sounds like a reasonable solution but an aluminum block would be much easier to drill. ya think?

[gthompson97]

Why would you put a nut on the end? The bolt threads into the tranny and that's what holds it in (or vice versa, I get the 420a/4g63 bolts messed up all the time). And if the holes are the same size and thread pitch, you should just be able to thread the bolt through the block and into the tranny (or vice versa again). And the block is cast iron, not aluminum.

[Blackcrow64]

Originally Posted by sierraxr7

The tranny hole would have to be drilled all the way through so that a nut could tighten it up and keep it secure. Sounds like a reasonable solution but an aluminum block would be much easier to drill. ya think?

Yeah, but if you screw up that hole then the whole block is gonna be screwed up unless you drill and tap the holes bigger... I donno... lol

[Blackcrow64]

Originally Posted by gthompson97

And the block is cast iron, not aluminum.

Wait, I thuoght it was aluminum?

[gthompson97]

Nope. Cast iron blocks, aluminum heads.

[Blackcrow64]

Ok ok, we discussed it... Its a cast iron block indeed... I have no clue what I was thinking... The bushings in those wholes are aluminum though we think. lol

[gthompson97]

Correct, and for the record...it's holes, not wholes.

[sierraxr7]

You are right it is cast iron and can't drill the tranny to put a nut on the bolt? I am the she trying to understand the he's. I only know mustangs. Anyway, There are I think 4 bolts going from the tranny to the block, this one bolt goes from the block to the tranny. For some reason the bolt threads through the block but no matter how good it is lined up the thread is not catching on the tranny side. It's so freakin frustrating. Imthinken this car ain't going to be worth puttin a body kit on after all.

[Blackcrow64]

Originally Posted by gthompson97

Correct, and for the record...it's holes, not wholes.

My bad, I was typing too fast. lol


I would try to drill out the tranny side... If you can't then I would make sure you can thread a bolt in from the other side before doing any drilling on the block first.