427 engine (part 2) - RHS block - Page 171

**Rich Z** · 07-18-2012, 08:31 PM

Yeah, I just ordered a set of 3/8 wobble extensions. That 36 inch guy is right pricey....

I took a look under the car and from the top, and I just can't even see the other bolts on the bell housing that would be above the center line. So I had to break out my flexible shaft camera to see if I could see anything that way. First let me back up a bit.

Just out of curiosity, I went back to the old videos I took while the car was out at Harwood's shop to see what the bell housing looked like, and also to see if Harwood put those bolts in place there.

Yep, looks to me that Harwood did in fact have those bell housing bolts in place. This is right before the drivetrain was put together with the engine and then mated with the car. So it looks to me that those bell housing bolts were in place.

So here's a pic I found online of the bell housing that I have.

I made notations near the bolts that hold the bell housing to the engine block, which can be compared with the bolts in the photos above this one.

Now, back to the flexible camera shots. All of the following pics were taken from the top of the engine, btw. I started on the passenger side, and it appears that both bolts A and B are in place. I didn't try to see if they were torqued down, however, not that I could have gotten a wrench onto them anyway.

BTW, I may have these reversed, as it was pretty tough looking at the photos and figuring out where exactly I was looking at.

Then I went over to the driver side. I believe it is bolt E that is the one I found loose and partially walked out of the threads. I didn't take any further pics of it this time. I tried to find the other two bolts C and D with the flexible camera, and I THINK the only one I was able to find is the one for bolt C.

I'm not positive about this, though, as I found another area that looked like it might be where a bolt goes, but it may just be the tab that is at about the 1 o'clock position in the main picture. I just couldn't get the angle on the flexible camera shaft such that I could see into any threaded hole.

But it appears that at least one other bell housing bolt is completely missing. I'll try again to find where that other bolt is supposed to be, but it won't surprise me in the least to find out that it is missing as well.

So, now the question is, what will it take to simply get to those missing bolt holes to put bolts in them and tighten up the loose one?

shakedown067 · 07-19-2012, 10:44 AM

Certainly looks like C should have a bolt...just comparing between that and the top image reviewing all the bolts and holes. The question is, just how long are those bolts? Wouldn't doubt you'll need more clearance than what you currently have.

**Rich Z** · 07-19-2012, 01:11 PM

It's pretty hard to tell how much clearance I have just looking at those pics, but in "C" that is just a piece of convoluted tubing covering we are seeing there, and not the firewall. I guess I do need to check to see if I have the remaining bolts in the crap I had in the trunk when I brought the car home. I know they are a 13mm head. I could pull out one of the bolts at the bottom on the cover plate to see exactly what they look like, I suppose.

I wonder what the chances are that anyone else had to try to get to the bell housing bolts in a situation like this that would know the best way to approach it?

shakedown067 · 07-19-2012, 01:19 PM

Yeah, I'm sure you aren't the first and unfortunately won't be the last. Good luck!

**Rich Z** · 07-19-2012, 02:38 PM

Quote:

Originally Posted by shakedown067

Yeah, I'm sure you aren't the first and unfortunately won't be the last. Good luck!

Well, with any luck, someone will be able to give me some pointers on the BEST way to tackle this. I'm still waiting on some tools to come in, which certainly won't be here till next week, so I'm in no hurry. I may order some of those "bendy" ratchet wrenches as perhaps I might need to get to one of those bolts at an odd angle where they will come in handy.

How do you fabricate a wrench? If I need something that is pretty much a custom angle, can I heat a wrench with a torch and just bend it? Or will it snap instead? Or am I just getting in WAY over my head with this?

shakedown067 · 07-19-2012, 03:00 PM

I've seen guys heat and bend their own wrenches...I just don't think they typically last long once you do that. Just use some disposable harbor freight wrenches! I've even seen open end wrenches welded to bars, like rebar, for added torqueability. You'd just need to grind the chrome off first of course.

**Rich Z** · 07-19-2012, 03:58 PM

I was able to get the flex camera shaft up to the spot where bolt #D should be, and yeah, looks like that one is missing as well.

So basically there were NO bolts holding the bell housing torqued properly in place on the driver's side of it. I'm thinking that perhaps that one bolt that is still there, but was sticking out about a quarter inch when I found it, might have been at least snugged up against the bell housing when Mike Carnahan was tuning the car, and perhaps that was enough to keep the housing from flexing under power, and why we didn't hear that noise then. Since that time, I took the car out three more times, and possibly the bolt then vibrated loose to the point where I heard that horrendous noise on 07-05-2012 and I then found it on visual inspection on 07-10-2012. So possibly with the bolt not even snug against the bell housing, that then allowed the flexing to take place (hoping that the bell housing didn't get cracked because of it) and that noise I heard on 07-05 to then exhibit itself.

Well, that's all speculation on my part, of course, but it all sorta fits the evidence, I think.

I dug through the box of bolts that was in my trunk when I brought the car home, and there are all kinds of bolts there with 13mm heads on them that look like they would work on the bell housing mounting. Different lengths, though, so I'm not sure what length bolts need to be used for those two missing ones. But it's apparently not because he didn't have the bolts available that Aaron didn't put them in place where they were needed to be.

CorvetteJohn · 07-19-2012, 04:08 PM

The rule for how long a bolt should be in aluminum is The tapped hole should be 2 1/2 times longer than the diameter of the threads. So if you have a bolt that goes into a 10 MM hole the bolt should be 25 MM long. Hope this helps you find the right length bolts in your box of left overs.

Don't forget to add the thickness of the tab on the bell housing to the length of the bolt.

If the thread depth to bolt contact is not long enough the bolt will not be able to hold the bell housing onto the engine.

You might want to experiment with getting some small round earth magnets to put in the bottom of a deep well socket. That will help you hold a bolt in the socket while you fish it into the hole on the bell housing. If you have trouble finding small round earth magnets look at Loews or Home Depot at the cabinet door hardware. They have a button that goes into the cabinet and holds the door shut with and earth magnet.

**Rich Z** · 07-19-2012, 04:16 PM

Thanks. I may pull out one of the bolts on the bottom of the bell housing to see how long that one is, since I'm guessing they should be the same length. The flanges on the bell housing look pretty thick, so I can probably use that as a guide.

I'm asking around trying to find anyone who has faced this challenge before to see how best to tackle this. I'm hoping for a solution that isn't going to be too painful. If the drivetrain still has to come out, this discovery is not really going to have gained me a hell of a whole lot.

CorvetteJohn · 07-19-2012, 04:29 PM

Now that you have the pictures of the missing bolts you might ask the fellow at the dealer that you talked too about the noise. If any one should know what is involved in getting those bolts in and tighten he should. He may have experience in how to do the job and make it look easy.