Turbo 400 Torque Converter Bolts Fell Out

ABC123 · Uber Guru

Turbo 400 Torque Converter Bolts Fell Out

seventy2plus2 · Canadian Poncho Superstar!

2 sets of frame brackets to accommodate the various transmissions. The forward brackets are for the shorter Powerglide, Turbo 350 & manual transmissions. The rear brackets are for the longer Turbo 400.
The driveshaft for the Turbo 400 is shorter, and uses different yokes & U-joints than other transmissions.

Prefectca · Poncho Master!

I remember torque converter bolts coming loose and the replacement bolts had a blue thread locking compound on them. If you loosen the remaining bolt you should be able to get all the bolts started and then tighten them up. I would suggest using blue loctite on the replacement bolts if they dont have a thread locking compound on them.

gtodrive · Guru

seventy2plus2 wrote:
2 sets of frame brackets to accommodate the various transmissions. The forward brackets are for the shorter Powerglide, Turbo 350 & manual transmissions. The rear brackets are for the longer Turbo 400.
The driveshaft for the Turbo 400 is shorter, and uses different yokes & U-joints than other transmissions.

Like Clint said. Mine has the 2 brackets too.

Prefectca · Poncho Master!

https://cnc-motorsports.com/859035-pioneer-general-motors-torque-converter-bolts.htmlhl

-- Edited by Prefectca on Sunday 24th of March 2024 03:01:56 PM

cdnpont · Canadian Poncho Superstar!

Hard on the pump bushing, but it should be ok.

I used ARP bolts.

I had all three loosen up when I did my 496 engine TH400. Sounded awful, scared the crap out of me..

4SPEED427 · A Poncho Legend!

ABC123 wrote:
The way this sounded it may have been a lot worse gone wrong.
That bolt screeched and clanged until it made its way out, probably, by the gap between the starter and the cover.
This would be the second one that has fallen out. Who knows when the first one went.
Unfortunately, now the converter has now shifted.
This is where I stop for the day.
Lots to think about.
What are the best new bolts for this car?
Stock bolts should be fine with a bit of Loctite on them.
If I loosen off the remaining bolt, will I be able to pry the converter back into location?
If you loosen the last bolt I think the other 2 will go in just fine.
Or is there permanent damage?
Should I just stop and haul the car to the local Transmission Guru?
Decided to lay there under the car and look at other things
In a 1969 full size, I have never seen this before.
Two transmission brackets.
The one not in use is consistent with my other frames.
Could the one in use have been added, to allow for a different transmission?
As far as I've ever seen without exception, all 65-70 B body Canadian Pontiac and Chev have the front set of brackets, whether they are used or not. The only time the rear brackets are welded on at the factory is if the car was assembled with a TH400.
Well, the drive shaft on this car is two inches shorter than my other shafts.
Yes, all Powerglides, 3 and 4 speed manuals and TH350 use the same length shaft, TH400 is all by itself for length. I don't have my books handy but as far as I know, in the first year of TH400 in our cars (1965), the U-joints were all the same regardless of whether it was a Powerglide, 3 or 4 speed manual, or TH400. Starting in 1966 the U-joint was different (heavier duty) on TH400 cars vs all other transmissions. My experience has been that the front and rear joints always match (1.125" OD cups) but it seems to me some books list the rear as different than the front. When I get a chance I'll see if I can find info on that.
I had thought all 1969 B-Bodies used the same drive shaft.
As mentioned above, TH400 affects both the length of it and the U-joint cup and cross measurement vs all other transmission choices.

I would love some input here

ABC123 · Uber Guru

Thanks everyone!

I am finding the on-line prices on the bolts all over the place.

If I only work 8 hours tomorrow, I will stop off at the local store to see what they have.

Blue Loctite will be on my list.

It's a good thing it happened in my shop during the carb test.

I would have never found the bolt on the road and would not have had a smoking-gun clue.

I never want to hear that sound again.

4SPEED427 · A Poncho Legend!

I once bought a Nova with a 327. Heard it run, great. Got it home, unloaded it off the trailer and it rattled so bad I thought it had a rod bearing gone bad. Yup, loose converter bolts.

DonSSDD · Canadian Poncho Superstar!

Time for a Muncie?

Canadian Poncho · A Poncho Legend!

Is it safe to say only the big block cars got the Turbo 400? If so this is one good way to verify an original BB car.

65 SD L79 · Canadian Poncho Superstar!

I bought a 67 caprice 327 400 turbo not sure about 69

seventy2plus2 · Canadian Poncho Superstar!

65 SD L79 wrote:
I bought a 67 caprice 327 400 turbo not sure about 69

I don't think Turbo 350's were around yet in 1967. Not sure about 1968, but Turbo 350's were definitely around in 1969. The green & gold 1970 2+2 w 400 sbc engine that I sold to Hillar had a turbo 400 tranny.

4SPEED427 · A Poncho Legend!

Canadian Poncho wrote:
Is it safe to say only the big block cars got the Turbo 400? If so this is one good way to verify an original BB car.

Starting in 1967 a TH400 was available on a B body Pontiac or Chev with a 327 or larger engine. 283 was only Powerglide (for automatic equipped cars) in 1967.

4SPEED427 · A Poncho Legend!

seventy2plus2 wrote:
65 SD L79 wrote:
I bought a 67 caprice 327 400 turbo not sure about 69
I don't think Turbo 350's were around yet in 1967. Not sure about 1968, but Turbo 350's were definitely around in 1969. The green & gold 1970 2+2 w 400 sbc engine that I sold to Hillar had a turbo 400 tranny.

I remember reading at some point that TH350's came out late in the 1968 model year. Has that ever been proven? Anyone know if this is true?

Canadian Poncho · A Poncho Legend!

Actually I see there were some 66's with small blocks that had THM400s.

4SPEED427 wrote:
Canadian Poncho wrote:
Is it safe to say only the big block cars got the Turbo 400? If so this is one good way to verify an original BB car.
Starting in 1967 a TH400 was available on a B body Pontiac or Chev with a 327 or larger engine. 283 was only Powerglide (for automatic equipped cars) in 1967.

4SPEED427 · A Poncho Legend!

Canadian Poncho wrote:

Actually I see there were some 66's with small blocks that had THM400s.

66 full size Canadian Pontiac or Chev with the claim of them being factory installed? That would be contrary to what the order guide says. But I've long learned to never say never. I don't think I've ever seen one on a 66 small block.

4SPEED427 · A Poncho Legend!

Any progress on this Randy?

ABC123 · Uber Guru

Performance Unlimited in London, Ontario, will have my ARP bolts Tuesday.

I will pick them up on my way home.

I need to get this car moving.

I will be under this car, bright and early Wednesday wink

ABC123 · Uber Guru

ABC123 wrote:
Performance Unlimited in London, Ontario, will have my ARP bolts Tuesday.
I will pick them up on my way home.

I need to get this car moving.
I will be under this car, bright and early Wednesday

They had them and sold them to someone else

I must have a twin confuse

65 SD L79 · Canadian Poncho Superstar!

ABC123 wrote:
ABC123 wrote:
Performance Unlimited in London, Ontario, will have my ARP bolts Tuesday.
I will pick them up on my way home.

I need to get this car moving.
I will be under this car, bright and early Wednesday
They had them and sold them to someone else
I must have a twin

when will they have more?

ABC123 · Uber Guru

I used some resources that I only want to use in an emergency.

Visited the builder of my M-20.

These are Professional, hardened, high strength converter bolts.

They were not sold retail.

You would not believe how heavy they are.

They themselves are at least 40 years old.

Dove under the car and followed my new set of instructions.

Removed the last bolt and hand threaded each bolt in until hand tight.

I rotated with a power bar on the front of the motor.

Then removed each one, blue thread lock applied and tightened.

Then around again with a final torque of 65 pounds on each bolt.

Fired the car up and it looks like the flex wheel has slight warp.

Nice view under here !

As much as we love our Canadian Pontiacs, the eight-bolt wheel design is a thing of beauty.

The 1967 Grand Prix goes home tomorrow.

Saw some other stuff.

Bolts loose on the exhaust and transmission pan.

Close only counts in horseshoes

biggrin

I couldn't leave this alone (OCD) smile

I do think the pump or seal has some damage but it was time to get this off the jack stands and call it a day.

-- Edited by ABC123 on Tuesday 26th of March 2024 08:59:45 PM