Bolt size?
Thread Starter
Pro
Joined: May 2006
Posts: 576
Likes: 0
From: Kernersville North Carolina
Bolt size?
finally installed the engine and trans in the car last night...prepping to attach the headers and hook up the engine (elec, lines, etc.).
when bolting the trans to the bell housing i found that the top 2 holes accepted a 7/16 course thread bolt, but the bottom 2 holes seemed to be larger as when i went to torque them down the threads skipped. anyone know what size threaded bolt should be used? it is a 69-350 engine in my 68, with a 4spd muncie. i didn't want to just start trying diff size bolts...
thanks
when bolting the trans to the bell housing i found that the top 2 holes accepted a 7/16 course thread bolt, but the bottom 2 holes seemed to be larger as when i went to torque them down the threads skipped. anyone know what size threaded bolt should be used? it is a 69-350 engine in my 68, with a 4spd muncie. i didn't want to just start trying diff size bolts...
thanks
Melting Slicks
Joined: Mar 2005
Posts: 2,093
Likes: 297
From: Midlothian VA
They should all be the same size.
If they are indeed stripped you are in the "deep doo".
You may have some good threads at the bottoms of the holes though so measure and see if you can use longer bolts. Not the best fix because you'll be living on borrowed time unless you can repair the holes. The weak connection between the lower bell housing and block will put quite the strain on the upper bolts and eventually the drive train geometry.
And there should be 6 bolts, not just 4. Two at the top, two at the bottom, and two near the alignment dowels.
If they are indeed stripped you are in the "deep doo".
You may have some good threads at the bottoms of the holes though so measure and see if you can use longer bolts. Not the best fix because you'll be living on borrowed time unless you can repair the holes. The weak connection between the lower bell housing and block will put quite the strain on the upper bolts and eventually the drive train geometry.
And there should be 6 bolts, not just 4. Two at the top, two at the bottom, and two near the alignment dowels.
Thread Starter
Pro
Joined: May 2006
Posts: 576
Likes: 0
From: Kernersville North Carolina
thanks, but i was speaking of the bell housing to the trans. the bell housing to the block is good, i just need to find the shield for the lower half. (?)
the 4 bolts for the trans to the bell housing are the issue. the upper 2 seemed to grab, but the lower 2 don't quite grab and 1 is popping off the threads when trying to tighten it down. i think the others are grabbing due to thread lock residue or dirt maybe...? should they be 1/2" bolts or what? i would think this would be a standard size. i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
thanks for the feedback
i did get the headers installed tonight and am prepping to start the engine for the 1st time, which a friend has said he'd help with
the 4 bolts for the trans to the bell housing are the issue. the upper 2 seemed to grab, but the lower 2 don't quite grab and 1 is popping off the threads when trying to tighten it down. i think the others are grabbing due to thread lock residue or dirt maybe...? should they be 1/2" bolts or what? i would think this would be a standard size. i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
thanks for the feedback
i did get the headers installed tonight and am prepping to start the engine for the 1st time, which a friend has said he'd help with
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
Originally Posted by Hammerhead Fred
They should all be the same size.
If they are indeed stripped you are in the "deep doo".
You may have some good threads at the bottoms of the holes though so measure and see if you can use longer bolts. Not the best fix because you'll be living on borrowed time unless you can repair the holes. The weak connection between the lower bell housing and block will put quite the strain on the upper bolts and eventually the drive train geometry.
And there should be 6 bolts, not just 4. Two at the top, two at the bottom, and two near the alignment dowels.
If they are indeed stripped you are in the "deep doo".
You may have some good threads at the bottoms of the holes though so measure and see if you can use longer bolts. Not the best fix because you'll be living on borrowed time unless you can repair the holes. The weak connection between the lower bell housing and block will put quite the strain on the upper bolts and eventually the drive train geometry.
And there should be 6 bolts, not just 4. Two at the top, two at the bottom, and two near the alignment dowels.
TRANS BOLTS.....YOU have MORE than 4 bolts connecting your trans to your bellhousing??
...redvetracr
PS: trans to bellhousing are 1/2 coarse
Drifting
Joined: Oct 2003
Posts: 1,426
Likes: 1
From: VetteMOD
St. Jude Donor '05-'07
Originally Posted by bwellisley
thanks, but i was speaking of the bell housing to the trans. the bell housing to the block is good, i just need to find the shield for the lower half. (?)
the 4 bolts for the trans to the bell housing are the issue. the upper 2 seemed to grab, but the lower 2 don't quite grab and 1 is popping off the threads when trying to tighten it down. i think the others are grabbing due to thread lock residue or dirt maybe...? should they be 1/2" bolts or what? i would think this would be a standard size. i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
thanks for the feedback
i did get the headers installed tonight and am prepping to start the engine for the 1st time, which a friend has said he'd help with
the 4 bolts for the trans to the bell housing are the issue. the upper 2 seemed to grab, but the lower 2 don't quite grab and 1 is popping off the threads when trying to tighten it down. i think the others are grabbing due to thread lock residue or dirt maybe...? should they be 1/2" bolts or what? i would think this would be a standard size. i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
thanks for the feedback
i did get the headers installed tonight and am prepping to start the engine for the 1st time, which a friend has said he'd help with
You are making big progress on your car. When you get done and your just itching to work on a car, come up to Ohio
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Melting Slicks
Joined: Mar 2005
Posts: 2,093
Likes: 297
From: Midlothian VA
Originally Posted by bwellisley
thanks, but i was speaking of the bell housing to the trans. the bell housing to the block is good, i just need to find the shield for the lower half. (?)
the 4 bolts for the trans to the bell housing are the issue. the upper 2 seemed to grab, but the lower 2 don't quite grab and 1 is popping off the threads when trying to tighten it down. i think the others are grabbing due to thread lock residue or dirt maybe...? should they be 1/2" bolts or what? i would think this would be a standard size. i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
thanks for the feedback
i did get the headers installed tonight and am prepping to start the engine for the 1st time, which a friend has said he'd help with
the 4 bolts for the trans to the bell housing are the issue. the upper 2 seemed to grab, but the lower 2 don't quite grab and 1 is popping off the threads when trying to tighten it down. i think the others are grabbing due to thread lock residue or dirt maybe...? should they be 1/2" bolts or what? i would think this would be a standard size. i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
thanks for the feedback
i did get the headers installed tonight and am prepping to start the engine for the 1st time, which a friend has said he'd help with
Sorry, misread your post.
Melting Slicks
Joined: Mar 2006
Posts: 3,341
Likes: 7
From: Connecticut
Originally Posted by bwellisley
i have a tap so i could re-tap them to a larger size if necessarry to prevent having to buy a new housing...
Muncies are notorious for the ears cracking/breaking off under normal conditions let alone making them weaker by enlarging the holes
I dont think you will find anybody that will disagree with this.
Bell housings are plentiful and inexpensive.
Also... find a shroud before you install the starter because the shroud gets installed before the starter.... I wouldnt think you would want to tangle with installing the starter twice especially if your running headers.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Originally Posted by Bob Onit
Also... find a shroud before you install the starter because the shroud gets installed before the starter.... I wouldnt think you would want to tangle with installing the starter twice especially if your running headers.
Thread Starter
Pro
Joined: May 2006
Posts: 576
Likes: 0
From: Kernersville North Carolina
Thanks, all!!
I'll get some 1/2" bolts to put in. If they do not feel as though it is right I will replace the bh. I will install the shield first. Thanks for the tip. I can't wait to fire it up...wish I didn't have to drive back to MI today! I have a friend getting married this weekend. This will be a big set-back in my work time...oh, well...Then next Fri will be my 1st trip to Carlisle!
btw...how does one get to post pics on here?
BW
I'll get some 1/2" bolts to put in. If they do not feel as though it is right I will replace the bh. I will install the shield first. Thanks for the tip. I can't wait to fire it up...wish I didn't have to drive back to MI today! I have a friend getting married this weekend. This will be a big set-back in my work time...oh, well...Then next Fri will be my 1st trip to Carlisle!
btw...how does one get to post pics on here?
BW
Melting Slicks
Joined: Mar 2006
Posts: 3,341
Likes: 7
From: Connecticut
Originally Posted by redvetracr
no need to replace the bellhousing.....any competant machine shop can heli-coli the holes.
...redvetracr
...redvetracr
I Helicoiled 2 stripped holes on my 70' El Camino bell housing and they loosened up in no time, had to tighten them repeatedly until they finally stripped out again.
Thread Starter
Pro
Joined: May 2006
Posts: 576
Likes: 0
From: Kernersville North Carolina
i agree, bob
i've tried this in the past on the stem for my mtnbike...not a good situation! i'll just replace if needed. i'm thinking that the upper 2 bolts bit in due to remnant thread lock since they are 7/16. i'll put in the correct 1/2 and make sure all is well before driving. however, it'll be a while until i get it to the point of registering it to be driven. i want to replace the suspension 1st, as i do not think it is safe to drive above 25mph until that is done...
i've tried this in the past on the stem for my mtnbike...not a good situation! i'll just replace if needed. i'm thinking that the upper 2 bolts bit in due to remnant thread lock since they are 7/16. i'll put in the correct 1/2 and make sure all is well before driving. however, it'll be a while until i get it to the point of registering it to be driven. i want to replace the suspension 1st, as i do not think it is safe to drive above 25mph until that is done...