bellhousing to tranny means shafts won't spin

rusmannx · 09-19-09, 01:41 AM

so after forever and a nightmare we got the tranny and tcase back together and working well.... until we installed the bell housing. for some reason, the more we torque the four housing bolts down the harder it is to spin the tranny input shaft until eventually we can't spin it at all.

backing the bolts off a full thread or two is enough to allow the input shaft to be hand-spun with ease. the nut at the end of the tranny output shaft has not been torqued down yet.

for fun, here is the bell housing from the inside.

here you will see the small gap between the tranny and the spacer-plate (this is a gm housing which gets this bolted to a 292).

shelfboy1 · 09-19-09, 07:34 AM

is the pilot bushing sticking out past the crank a little .have used the same setup you have and no problems .good luck

Sharp38 · 09-19-09, 09:14 AM

Odd problem for sure. I think I would take the installation completely apart and check for fittings starting with the transmission. Make sure the bearing retainer is pulled up tight against the bearing and all turns freely. Check for cracks in the casting that might cause binding when you tighten it up. Put the adapter on and tighten that up (without bell housing). Any change. Make sure there is clearance around the bearing retainer on the transmission. If all ok, next step to bell housing.

Don
www.wolfcreekrodworks.com

Downey · 09-19-09, 11:21 AM

If correct pilot bushing is properly seated into back of crank, then I suspect your aluminum adapter plate is not thick enough---just a rough guess!!!

rusmannx · 09-19-09, 01:24 PM

well the adapter has been on for who knows how many years, although, the bell housing bolts may have been loose enough all that time to not cause binding.

EDIT: what/where is the pilot bushing?

so i'm wondering if this is a home made adapter. it doesn't have any stamping on it which would indicate that it was purchased somewhere.
here is a SOR plate for 3speed to v8 conversion. anyone know the width of this?

amaurer · 09-19-09, 01:52 PM

Quote:

Originally Posted by rusmannx

EDIT: what/where is the pilot bushing?

In the end of the crankshaft. Is your problem happening when you bolt up everything to the engine, or just when you put the BH on the tranny?

Pilot bearing issues only apply when putting the stack onto the engine, so it sounds like this is happening to you when you're attaching the BH outside of the truck... so I'm thinking not a pilot bearing prob?

rusmannx · 09-21-09, 12:20 AM

that is what i thought. i have not yet bolted it to the engine, this is happening when i bolt the bell housing to the transmission while on the bench. here are a couple more pics and with the bell housing off.

shelfboy1 · 09-21-09, 04:15 AM

now i get it .just geussing but the depth of the bearing retainer in the adapter doesnt look deep enough for the bearing .probably should measure the thickness the bearing is sticking out and the depth of the adapter.i never liked that style adapter and have thrown several of them out .

rusmannx · 09-21-09, 03:14 PM

Quote:

Originally Posted by shelfboy1

now i get it .just geussing but the depth of the bearing retainer in the adapter doesnt look deep enough for the bearing .probably should measure the thickness the bearing is sticking out and the depth of the adapter.i never liked that style adapter and have thrown several of them out .

and replaced them with what from where?

i'm wondering if i get a sheet of cork or gasket paper it might space it out more. this didn't have a gasket in between any surfaces when we pulled it apart.

Sharp38 · 09-21-09, 07:18 PM

I think you may still be missing the issue. The outside of the bearing (with the snap ring) is tight in the housing when you bolt on the bearing retainer. If the bearing protruded too much, you would see a gap when you bolted it down, but it wouldn't restrict the rotation of the shaft. I have one other thought you might check. Generally, the input shaft mates to the output shaft with some needle bearings. One possibility is that you have one needle bearing that fell out and is laying between the two shafts. When you tighten things down, it clamps down on the input shaft. Try putting the retainer on and progressively tighten the bolts while testing rotation. If you can get the bearing retainer completely tight and still rotate the shaft, it's another problem

Don
www.wolfcreekrodworks.com

rusmannx · 09-21-09, 09:41 PM

Quote:

Originally Posted by Sharp38

I think you may still be missing the issue. The outside of the bearing (with the snap ring) is tight in the housing when you bolt on the bearing retainer. If the bearing protruded too much, you would see a gap when you bolted it down, but it wouldn't restrict the rotation of the shaft. I have one other thought you might check. Generally, the input shaft mates to the output shaft with some needle bearings. One possibility is that you have one needle bearing that fell out and is laying between the two shafts. When you tighten things down, it clamps down on the input shaft. Try putting the retainer on and progressively tighten the bolts while testing rotation. If you can get the bearing retainer completely tight and still rotate the shaft, it's another problem

Don
www.wolfcreekrodworks.com

i've considered this as well, i'm just struggling with the idea of pulling the tranny apart again. good point on the bearing retrainer.

also, i've always wanted to know what became of that feed store. it was downtown right?

rusmannx · 11-03-09, 01:29 AM

alright. finally got some time to get back into it.

right now i've got the tcase about 1/2" away from being tight against the tranny. the bell housing was tightened down to th be trans and the bolts backed off 2 turns.

i can spin the tcase output shaft pretty easily (not perfectly free though).

the input shaft on the trans will barely spin by hand but seems to make a bumping grinding noise as it goes. since the two shafts have different characteristics i am lead to believe that it is not a roller gone sideways between the input and output shafts.

i'm wondering if the tightening down of the bell housing is mis-aligning some of the gears on the input shaft with those on the counter shaft.

any thoughts?

Pin_Head · 11-03-09, 09:16 AM

Quote:

Originally Posted by rusmannx

any thoughts?

It is a very strange problem.

I would start looking inside the tranny; first by pulling off the top cover and checking the clearances between the input gear and the synchro assembly. Do you have the transfer case installed and the nut torqued down on the output shaft? This would make sure that the shaft is seated against the output bearing.

rusmannx · 11-03-09, 06:22 PM

the cover is off the tranny now and i can't tell by looking if there is a binding or clearance issue.
the tcase is not snug up against the trans but i get your point. i would think this would have more to do with the tcase not spinning, not the input shaft.

i'll tighten it up and see what that gets me.