When I installed the engine, I was torquing the big bolts on the frame horns and one of them seemed not to want to pull the full torque. It felt like the threads were going to pull so I stopped at about 80 ft lbs. I think the problem was caused by the Kafer bar I put in that uses 1/4" plates between the frame horn and the trans bracket. This spaced the bolt out enough so I think the threads on the stock bolt are too short. This bolt is special with a large shoulder. Has anyone seen longer bolts available from some other VW or Porsche? If I can't find a longer bolt, I'm going to have to put a helicoil in it. I've seen the kit for this but it and the drill is going to be big bucks. Does any one have experience with fixing this? I thought about turning the bolt head down to get more thread length.
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Have you looked at McMaster-Carr?
What is the torque supposed to be on that bolt?
I believe the correct torque is about 150 -160 lbs.
Thanks, Alan. I don't remember checking that when I did the Suby last year. Bet mine are less than that. Will check 'em.
Do any of you guys have a couple of the 73 and up longer shank bolts with the smaller head? I can't find any.
Sorry, caption didn't transfer. I need the lower style bolts. Thanks. Frank
Any VW supply house CIP1 etc.
We loosened our frame horn bolts today and were surprised that they were not torqued on very tight. I just looked at the torque table in Muir's book and it says nothing for those bolts that I could see.
An online search showed transmission carrier to frame bolt should be 166 ft. lbs. Mine were nowhere near that.
Bentley, Haynes and the SAE all say 166 ft. Lbs. for those bolts.
Stroud, are you thinking what I am thinking?
That is part of the fun here. Between David and Ed, I never have the first clue what these guys are thinking. Tune in every day just to find out . . .
Not sure Ed , so spit it out I guess.
If I am thinking what your are thinking...then no, I don't think so as they were snug but certainly not 166 ft. lbs.
I've checked McMaster Carr to try to be nice. Complete, total strike-out.
Well, if McMaster-Carr doesn't have them, try Belmetric in Tyngsboro, MA.
David (and all): both of us have experienced minor drivability issues post Soob-swap. David has experienced some clutch chatter. I have a little less of that maybe than him, but I've had some "shifting" of the gear spots while driving--even lost 4th once for a while. It just went away.
So I think my engine has been rocking ever so slightly under load. I was thinking that my home-built mid-mount transmission mount was the culprit, because usually anything I make for myself is just not quite up to professional snuff.
But now I think that maybe--just maybe--it's the fact that I almost certainly didn't put 160 ft-lbs on those tail bolts. More likely about 100. And since I turned the mount cradle backwards (again, looking for, and getting, just a little bit more forward tuck to the power train) I might have crushed the sheet metal on those a bit, making everything just loose enough . . .
so that my home-made mid mount's shortcomings are made manifest.
So I am thinking that if I crank on those big bolts quite a bit more, I might solve my shifty shifter problem, and Stroud might do the same for his chatter if he does the same with his torque wrench.
That's what I'm thinking.
Could be a good link, Ed but my left rear tranny mount is toast and I'd put my money on that first in my case. It always could be a combination of things of course.
I'm going to renew all my tranny mounts with good quality Stock spec mounts and then reinforce the whole shebang with a very stout rear engine mount with some stiff rubber mounts under a bit of preload. I have a pair of stock Soob mounts in nice shape from the donor EJ25 engine so I'll likely figure a way to mount them.
It's nice that we're all learning more about this stuff....proper torque this time at least.