Tk8398
Tk8398 HalfDork
4/7/22 12:49 p.m.

I have been stuck for weeks trying to get the engine mount back in my Boxster, and I think that part of the problem is that the threads are too dirty to get the upper two bolts back into the engine easily enough to fit everything back in. 

I have this one from Amazon

but it doesn't work because it's too short/the hex at the top is too big.  Does anyone know where I could find an alternative to the ARP one of the same style?  Per ARP they are at least 6 weeks out from getting any in stock, and the only places that say they have them in stock are are on ebay in other countries and they are ~$100 (msrp is under $30).

obsolete
obsolete HalfDork
4/7/22 1:05 p.m.

You can make a serviceable thread chaser by cutting slots in a bolt with a grinder. Clean up with a small file afterwards. Good luck.

David S. Wallens
David S. Wallens Editorial Director
4/7/22 1:16 p.m.

FWIW, I couldn't find ARP rod bolts for the M3. I called everywhere, and no one had them. 

So I set up an eBay alert. I scored the bolts a week or two later. I did pay a 50% premium, but I got them. 

Pete. (l33t FS)
Pete. (l33t FS) MegaDork
4/7/22 1:19 p.m.
obsolete said:

You can make a serviceable thread chaser by cutting slots in a bolt with a grinder. Clean up with a small file afterwards. Good luck.

It works a lot better if you cut the slots deeper than the root of the threads, as I discovered the hard way.

spandak
spandak Dork
4/8/22 12:51 a.m.

Just curious, what is the exact issue with the threads? Are they torn up or just dirty? 
if it's just dirt why not blow it out with some brake cleaner? 
 

and if memory serves the upper bolts only need to be loosened as the mount holes are open slots. That should make the bolts easier to get started at least. 
 

just spit balling. 

Mr_Asa
Mr_Asa PowerDork
4/8/22 1:00 a.m.

In reply to spandak :

If there was any oil or grease involved at any point its not about blowing it out anymore, you gotta dig the grease and dirt out.  Means something mechanical.

Tk - in addition to cutting a bolt you could try a circular wire brush chucked up in a drill?  That plus some WD40 to loosen the muck, and then when that is cleaned you can move to carb cleaner.

Paul_VR6 (Forum Supporter)
Paul_VR6 (Forum Supporter) SuperDork
4/8/22 9:09 a.m.

I tend to use ss "bottle brushes" on our Honda which has some tragically fine threads on structural bolts. Any corrosion and there is no way these pos go back in. I have some I have trimmed down and chuck in a drill. I then shove them into the bolt hole and run the drill in reverse very slowly and pull the brush out. After that I will try and install a bolt without trying to final assemble to make sure it goes in without issue, if that doesn't work I may chase with a tap and repeat with the brush. Usually by then all is well.

Tk8398
Tk8398 HalfDork
5/13/22 12:34 p.m.
spandak said:

Just curious, what is the exact issue with the threads? Are they torn up or just dirty? 
if it's just dirt why not blow it out with some brake cleaner? 
 

and if memory serves the upper bolts only need to be loosened as the mount holes are open slots. That should make the bolts easier to get started at least. 
 

just spit balling. 

They are just dirty as far as I know, the bolts came out ok but won't thread back in by hand.  They will thread in with a wrench/socket but it would take about the same amount of force as cross threading them and since it's so cramped and at a weird angle I would rather not try it.  I can't figure out how to get the engine mount to clear the floor of the car either, but I was hoping with cleaner threads it would be easier to adjust how far they are threaded in to hopefully get it to work.  I still have no idea what to do, ARP can't get the material to make any more of those thread chasers so they say it will be at least several months at the earliest to make any.  If I can't figure something out soon I will probably just have to try to figure out a way to support the engine from the top so the car is movable and get rid of it, I don't even really care about it anymore, I bought it a year ago and have barely driven it and I hate working on it.

MyMiatas
MyMiatas New Reader
5/13/22 11:53 p.m.

I would call a local machine shop (one that has CNC machines). They would have a tap on hand or a supplier that would.

The wire brush idea came to mind first and I gave that a "thumbs up" for adding that answer.  A product call Deep Creep for stubborn bolts would help with the whole cleaning process,wire brush or tap.

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