Copilot

So I was working on my engine last night; pulled off the clutch housing and housing and the pressure plate/clutch assembly, all so that I can bolt the block to my engine stand.

So there I am, minding my own business, threading a bolt into the block for the mounting arm on the engine stand and this happens:





Seriously - there was nothing abnormal going on, and suddenly there's just a light "pop" (even though I wasn't putting a lot of pressure on the wrench), and off comes this piece.

Am I totally screwed? Part of me says "eh, it's only one of four bolts, they don't bear TOO much weight, and at least half of the thread is still biting".

But then part of me broke inside when I saw an actual piece of the block snap off.

Marcquito

Perhaps weld the piece back on and rethread the hole a bit larger?

Also, what type bolts are you using to hold the engine onto the stand? Make sure they're case hardened to prevent trouble. I had to order a set from Fastenal to do the job.

bordin34

Looks like you bottomed out the bolt in the block. I use all thread when bolting up an engine to a stand. That way you get 100% thread engagement without worrying about bolt length or bottoming out the bolt. By using all thread you are basically making engine mount studs.
Edit: Here is my iron 440 big block with all thread.

V2Rocket

I saw this happen a few months ago, likely the bolt was crossthreaded and overtightened in the hole previously. (The owner was loosening it, not me )

It is fixable by TIG-welding.

bordin34

Do you have to preheat cast aluminum like you do cast iron?

xsboost90

the thread is open on both ends- but I've seen lots of them like that, installed and re-installed with no issues. Don't worry about it.

Copilot

Sweet, thanks! I would get it TIG welded if I could, but I honestly don't think there is anyone withing 2 hrs of me that is qualified to do it... or at least, that I would feel confident with working on my engine.

techartisan

Your profile says your in coos bay, or....there are always good welders near the coast. They might be more familiar with boat engines then porsche engines but your looking for a welding job not a rebuild. A quick search of a couple of boating forums and a review of their sites gives me this list in my order of preference....if I were in your location and situation.....
http://crockettwelding.com/
http://coastmetalworks.com/
http://www.koontzmachine.com/

mytrplseven

I love it when the rennlisters jump in to help another with obscure but very helpful info like techartisan offers. Good on ya.

Copilot

Thanks! I'll admit I'm pretty wary of any kind of "services" in the area, based on some pretty bad experiences with just about.... everything - but if they've got decent ratings, I'll give them a shot. Thanks for checking that out for me - I feel kind of silly for not doing the same now..

xschop

25 Yrs of heat cycling on old alloy casting causes brittleness. It's normal.

JohnKoaWood

First line of OP made this come to mind... "So, I'm just working on my motor..."

Po924S

I'm useless here but just wanted to say - those 997 turbo rims on your 951 look ABSOLUTELY amazing.

Copilot

Thanks! The wheels were a bit of a gamble when I got them, not knowing how well they'd fit or look, but I'm VERY pleased. Gives the car a real modern look without detracting from the classic 944 look.

And to John - ABSOLUTELY not. It was an engine block. Of course I knew to use a dead-blow hammer.

FRporscheman

My '84 NA has one of those 4 holes broken like that, and it's been fine for the last 8+ years. I discovered the broken hole 8 years ago, who know how long before then it actually broke?

For me it was the lower left one, I think.

Always make sure the holes are clean. For every bolt size, I have a bolt with a groove cut in it with sharp edges, kinda like a tap, and I put oil on it and thread it in. The sharp edge sorta chases the threads, the groove catches all the dirt and the oil helps both functions. A tap would work too but I think a grooved or slotted bolt is much easier to work with, especially in tight spaces.