Anyone ever had to drill out a snapped torque converter bolt??

sb001 · 11 April 2018, 02:07

Wow, that bolt got pretty jacked up!
I hate to say it but I believe evwparts sells the aftermarket bolt like what I used--at least that's what the picture on their website shows. Apparently it cannot withstand the same torque as the original German ones, so if you use those I would go very slowly in incremental steps to try to get it to 18 ft/lbs, or set it a little lower. I was trying to go in steps with mine and was only at 15 ft/lbs when that head snapped off.

autonewbie · 11 April 2018, 05:42

When I replaced my torque converter bolts I used Allen head bolts that were bought locally. However I can not remember exactly where I bought them. Sorry, my memory is shot.
They have been in use for at least 4 or 5 years without issue.

sb001 · 11 April 2018, 15:45

Hooper, I just stumbled across these from Mofoco:

http://www.mofoco.com/item/VW_Torque_Converter_Bolts_Used_All_Autostick_T2_T3_Fully_Auto/2970

Original German bolts $2 apiece, heck of a deal.

Hooper454 · 11 April 2018, 22:13

Thanks for the heads up on the bolts. When mine come in, I might just test them and make sure they withstand 20-25 ftlbs in a vise before installing in torque converter.

sb001 · 12 April 2018, 02:35

Out!!

Just drilled a groove in the top with a dremel tool and backed it out with a flathead.

Have a set of the good used German bolts on the way from the link I posted above.

autonewbie · 12 April 2018, 02:47

Congrats on getting the stub out. Hopefully we both will get our cars rolling for a long time between repairs.

volkenstein · 12 April 2018, 03:56

Sb,
Thank heavens no one locktited it (Lee - paging Lee)!.

Still a nasty thing to have to have to work on....good job.

I suspect the S/H TQ bolts will be of massively higher quality than 6 point zinc plated ungraded stuff.

Volkenstein

sb001 · 12 April 2018, 04:19

Hope so Volkenstein! Pulling the engine made it MUCH easier.
The link I posted above for the German bolts actually offers two kinds- the regular 6 point and the more uncommon 12 point head! I actually couldn't decide so I ended up ordering 4 of each

sb001 · 12 April 2018, 04:21

Quote from: autonewbie on 12 April 2018, 02:47
Congrats on getting the stub out. Hopefully we both will get our cars rolling for a long time between repairs.

Good luck to us both!! Hope the diaphragm repair kit solves both our troubles!

paulheger · 12 April 2018, 07:55

Congrats!!

Hooper454 · 13 April 2018, 19:02

Received my "new" torque converter bolts today. Added a washer, put it in a vice screwed into a bolt. Attempted 20 ftlbs. Only made it to 9.9 ftlbs before the socket started stripping on the head. Tried two different bolts with two different sockets, (both snap on). Same result. Looks like I am ordering the used ones.

Also ordered a fuel pump rebuild kit. Ended up reusing half the old parts because of poor quality or incorrect design. Is there a go too place for quality replacement parts?

Dan

sb001 · 14 April 2018, 01:32

Not really- as far as the aftermarket online VW vendors go it's just really hit and miss. Some of it is decent quality and some of it is junk. You might try the samba classifieds or the parts section here-- also there are some vendors like Bugcity that sell quality used German stuff and even have a good selection of NOS parts but you'll pay premium price for them.

I happen to live pretty close by to a VW salvage yard that has always had whatever I was looking for, sometimes this guy asks very reasonable prices for his stuff and sometimes it's way high. I found an ultra-rare thermostat flap pull cable there that he only wanted $20 for. But i tried to buy an autostick control valve from him once and he wanted $100. Go figure...

That's why I was surprised to find those German TC bolts on the Mofoco website for $2 each- they're like $5+ everywhere else.

tmea · 15 April 2018, 22:31

Honestly, that seems like a tremendous amount of torque for such a small non-hardened bolt. I have done mine a few times and do not torque them because the spec seemed erronious to me. I just make sure the threads are clean and dry and I tighten with a small ratchet.

I would bet that if you went to the hardware store and got a new hardened M8 bolt and nut and repeated the experiment you would get the same result. 20-22 ft.lbs always seemed to be an error to me. If you think about it, there isn't a great deal of stress on these four bolts if they are just tight. All of the forces on them are lateral and not axial (where torque is critical). The considerably larger (and hardened) connecting rod nuts only take 24 ft.lbs! The only time I have seen damage is when one comes off. I check routinely and mine and they always remain tight.

I wish I had a scientific recommendation for torque but 20-22 ft.lbs has to be very wrong. If you absolutely must torque them I'd go for around half of the spec. Any other thoughts out there?

Tom

sb001 · 15 April 2018, 23:07

You could be right Tom-
although I will say that I managed to torque my other bolts down to 18 ft/lbs with no problem (although I took it REAL slow.)
Remember that these bolts were cheap aftermarket bolts. The original German torque conveter bolts have an extra contoured and grooved washer that I can only think helps absorb some of the tightening by "biting" against the torque converter tabs and allows those bolts to take more stress than these cheaper aftermarket bolts. I will tell you that I used this same torque spec on a 72 super I bought (and resold) last year that came with the original German bolts and I had zero problems torquing them down to that spec. I DO suggest that you tighten them in incremental steps though just to be safe.

tmea · 16 April 2018, 01:46

I did some experimenting on the topic a while back. I wanted to replace the TC to FP bolts with something a little more robust. I got some hardened hex bolts because it is difficult to strip them, both the threads and hex socket. Not usable even when cut down because they cannot be made to clear the inside of the bell housing. I tried a couple different options to no avail.

So, my guess is that VW got themselves in a spot and had to create or special order those bolts with the narrow head. With a head that small I think 12 points were necessary to get any significant torque on them.

I really do believe that the spec torque on those bolts is an error by at least X2. Look at any similar or larger bolts on the car and compare. As before, the rod nuts which are hardened, under much more stress, have much more contact area and a 24ft.lb spec. Others are similar. There is a fairly linear relationship between the size of bolts and their torque spec. The TC-FP bolts are off the charts for torque spec IMO. They are for a fairly low stress application. It would be interesting to search this site and the samba to see how many have had the threads stripped, broken the captive nut off or stripped the points of the bolt while torquing to spec.

The newer replacements. I have some and have tried them but did not use. They appear to be of softer steel and do not have a taper at the start of the threads so they are difficult to get started although I think you could grind a slight taper on the end like the OEM ones.

Tom