Did I screw up my TH350?

[#1CutlassSupreme]

I admit it...I'm a novice...

I had my TH350 rebuilt and when I was bolting the bell housing to the engine I heard a pop...

Here's what I did and you can tell me if I'm screwed.

1.) I bolted the flexplate onto the engine first
2.) Put a quart of fluid inside of the torque converter
3.) slid the converter onto the shaft then spun it till slowly it slid down a second time and was about a fingers width away from the bell housing
4.) Lined up the bellhousing and the converter bolt holes with the flexplate holes
5.) started threading the converter bolts with the flexplate by hand, but left them pretty loose to manuever

There was about a 1/4" gap between the bellhousing and the engine after starting the bolts, but when I went to tighten the bellhousing bolts down I heard a deep "pop" noise. Did I screw something up or could it have been the front of the converter mating with the crank shaft?

Please tell me I didn't kill the trans...

I took everything back off out of sheer panic and spun the converter again and it seemed to spin smoothly like before.

Did I destroy it? If I start it up and had done something what risk do I have?

if anything did happen, you'd probably see a split or crack along the locating dowl pins of the transmission bell housing.


the only other possibility is destroying the torque convertor bushing or seal- but it sounds like you took great care in pre assembly, so i doubt it.

[Bluevista]

Chill dude.

Sounds like you did everything right to me too.
Mine did that when I was tightening it, it was just binding and it popped when it freed up when the bolts were tightened, that deep hollow sound. Possibly the converter sliding back on the shaft and clunking, doesn't touch the crank as far as I know.

If the housing isn't cracked or anything, as scubastever mentioned before, I wouldn't worry about it either.
If it looks good just put it together and try it, nothing you're gonna do about it now anyway.


Just my two cent woof,

Allan

[gearheads78]

Sound like you are making too big of deal. Slide the converter in the trans until it stops. While slightly pushing in start spinning it to will fell it drop in farther. Since you are new and don't have a feel for it spin it back and forth until you are sure it will not go any deeper. Put the transmission in the car and bolt it tight to the engine. Do not mess with the converter until the bell housing is tight. Now just in case the converter slipped back out a little push and spin to make sure its all the way in. Now measure the gap between the converter face and the flexplate. You want this to be 1/8-3/16" If its more (it usually is if aftermarket converter) then get get three matching washers that are the right thickness to take up the space needed.

example is the air space is 1/4" then use a 1/16" washer (spacer) to take up the space. The washer goes between the plate and the conveter. Install the first bolt and get it just finger tight. Its now OK to slide the converter out toward the flexplate. Rotate the motor as needed to install the other two bolts. If bolt and nut I use lock nuts. If the converter is threaded I use locktite red.

[J-(Chicago)]

I'd locktite the flex plate bolts to the crank as well.
Also, I never re use old flex plate bolts. Sounds anal, I know, but it's better than a spiked disc sawing your leg in half.

[BILL DEMMER]

it sounds like you didn't have the torque converter fully seated in the end of the crankshaft. that "pop" was the tc seating.

did you put a thin layer of trans-gel or wheel bearing grease on the sealing surface of the tc before hanging on the trans? it is necessary to lubricate the sealing surface and seal lip before initial start-up.

blue thread locker is a very good idea along with proper torquing of the tc to flex plate bolts.


bill

[#1CutlassSupreme]

Awesome! Thanks for all of the advice. I thought that I had done everythign right, but the guy that rebuilt the tranny kinda scared the heck out of me when he told me how to properly put in the TC.

Don't mean to freak out, but it's just been my luck on the last few projects to trip at the finish line and have some kind of catastrophic failure.

AMH, you hit the nail right on the head. It was a deep popping noise and I think you are right about it just binding up. I didn't see any cracks or splits in the bell housing so I think I'm good.

Gearhead, Scuba, J-, and Bill, thanks for the procedure advise and on using the locktite. I did lube up the end of the shaft of the TC before it put it in so we're good there. I didn't locktite the flexplate bolts, but they are torqued to factory specs. I just followed the manual. They're down at 60 ft/lbs each so I think that they'll be okay(?). As far as the converter to the flexplate I'll definitely pull the dust cover, climb underneath and locktite those.

Anyway, thanks again for the help. The car is coming home from paint on Monday so I'll post some pics soon.