torque converter bolts..

[diesel4me]

OK,I'm puzzled..been a long time since I had to bolt up a torque converter on an older GM...

I have a TH350 mated to a '70 307,someone removed the bolts that attach the converter to the flex plate...and lost them..I need to know how long the bolts need to be,and if the nuts are typical ones with a 9/16" hex or something different..

Far as I recall,they were just regular 3/8" nuts and bolts (grade 5 or 8) that I used on my 70's vehicles,but I cant seem to get a nut on the converter side to align with the hole on the tab welded to the converter...I do not recall the nuts being "special",or having to grind one side down to get them to line up in the past..and you cant insert a bolt from the converter side with the head facing the converter..

Anyone clue me in ?...

 

[Shawn]

I would imagine 3/8 -24, .75" long

https://www.summitracing.com/parts/arp-230-7301/overview/

 

[nvrenuf]

If you can't get a nut in between the flange and convertor body, are you sure the flanges aren't tapped?

 

[diesel4me]

The tabs welded to the converter are quite thin,like less than 1/8",not thick enough to have tapped threads..

Those bolts & nuts dont look "special",and if anything,the nuts have a washer made to them,which I would think would make them "too big" to fit behind the converter tabs--I see one comment saying they had a struggle to get them aligned and installed..
Maybe its just me,my sight and patience isnt what it once was..

I'm just trying to mate the TH350 to the engine so I can try starting it "on the ground"...to see if it'll run,or has a knock,etc...
I bought both cheap,just want to hear what it sounds like..

I don't think the engine would like to start or idle well,without the flywheel effect of the torque converter ,if I took the trans off it...also the converter is not wanting to go into the crank pilot,but I didn't mess with it that long,it was too cold in my garage--I looked up the engine code and it was originally hooked to a 3 speed manual according to the code..

I might have to pull the tranny off and see if some imbecile left the pilot bushing in the crank or just pounded it in further..the tranny has a chunk missing on the passenger side ,where the upper bell housing bolt went,that held the dipstick tube in place--maybe that is why..it is bolted flush to the engine though...
Going to fool with it more tomorrow when it might hit 50 here..

 

[Justin V]

Engine will run fine without the trans installed...

 

[rampage]

Engine will run fine without the trans installed...

 

[diesel4me]

In a vehicle,yeah,I'd be OK--but with it either hanging by a chain on my engine hoist (just barely off the ground),or bolted on an engine stand,it'll be scary enough with the trans installed and bolted up..

I'm regretting junking a GM 4x4 front frame section a few years ago,it was a good thing to have around,for test running an engine..but if I still had it,I'd probably be stupid enough to try making a buggy out of it and injure myself.....I just want to see if the engine sounds OK,if not,I may just load it and the Th350 back in my truck bed, and cash it in for scrap..
I have to remember to make up a "loop" of 5/16" brake line to join the two tranny cooler ports together--I already had ATF squirt 15 feet just out of the snipped lines ,cranking it over with the starter,I "oiled" the steel arches on my quonset --good thing I was not standing in its path!..