Good morning,

I am about to test my engine (out of the vehicle) and have bolted on the bell housing in order to mount the starter. I have a book for a Volare, but do not see any torque specs. In my other books it will have the action (aka install the bolt) then the torque specs listed next to it. There is a part in the book which seems to talk about torque specs per bolt size and hardness level, but I thought I'd ask for reference material recommendations before moving forward. I am specifically concerned as I have bolts going into the aluminum bell housing and my threads are already a little stripped.

Sincerely,

Paul Barrow

Which book? If it's a 1978 Factory Service Manual for the cast crank engine you have, all the tightening specs for the engine and attachments are on 9-82 and 83 for the 225 slant six...

If it's a Haynes or Chilton...good luck there.

It's a Chilton, poo. I'll try and find the factory manual, but in the meantime can anyone provide the torque specs for the bell housing bolts? Looks like I have three 3/8ths and three 7/16ths bolts for the bellhousing as well as the stud and bolt for the starter.

Sincerely,

Paul Barrow

The factory torque specs are not needed in this situation and as you noted, tightening a weak thread to those specs would likely result in thread failure
( the FSM calls out 28 FtLbs for the 9/16 housing to engine bolts & 45 FtLbs for the 5/8 trans to housing)

I would tighten by hand to around 10 ftlbs and then re-check and go a little tighter after you run it.
Just my 2 cents....
DD

yea...I gotta say...if you're using parts with stripped or weak threads, why worry about torque values? That's like worrying about the best oil to use on an engine that you know has a some missing rings.

Sure Greg,

Only one is stripped and with that aluminum I know if I put much pressure on any of them I will have a similar issue, hence my look for the torque specs. I am debating either placing a nut on the back of the stripped hole or boring and tapping it to a larger size. There would be space in the bolt hole located on the block for that second option.

Paul

For what you're doing, use these values:

3/8-16 thread - 15lbs

7/16-14 thread - 20lbs

If you can't get that to hold without stripping, you can't count on them anyway.