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Author Topic:   Breaking Saginaw Trans Help
tyfyter
Dirt Roller

Total posts: 19
posted August 30, 2004 02:17 PM  
Been breaking Saginaw 3 speed Trany ears and alum bell housings all season long. Really starting to drive me nuts. The ears break usually starting with the driver's side top ear. Then the passenger side top ear will break next. They don't break out by the bolt, they break at the base of the ear and crack into the case. Then fluid will start seeping out. Hopefully someone can help. Here's a rundown of the engine and trans setup:

83 Monte Metric chassis, 400 SBC engine with original factory crank, original factory balancer, and original factory flexplate. Ram triple-disk clutch with hydraulic throwout bearing. Using Saginaw 3 speed transmissions. Solid Moroso engine mounts and solid mount pads welded down.

Here's some of the things I've tried to remedy my problem:

I tried the solid engine mounts with the factory crossmember and a soft trany mount. Tried adding all types of roll cage bars to stiffen the chassis. The chassis is pretty stiff now. I tried mid-mounts and let the trany hang with no crossmember. Put the crossmember back in and tied a solid trany mount. The drive shaft has been balanced with new universal joints and the slip yoke sits 1" out of trany. Driveshaft only travels about 1/4". I've changed the 9" pinion yoke.

Currently, I'm running the old, heavy cast iron bellhousing. It seems to be able to hold up. But the trany ears keep breaking at the top and crack clear into the case. Whenever I try an aluminum bellhousing, it cracks right in front of the starter. I thought once I took out the crossmember and installed the mid mounts that would fix it, but it still breaks the same way. Anyone have a clue as to what might be causing all of this stress and breaking trany ears. I can put in a new trany and break it during the first heat.
Any info is greatly appreciated. Any other info needed I can provide.
Thanks



pit_boss
Dirt Forum Racer

Total posts: 80
posted August 30, 2004 08:19 PM  
Dumb question, but you havn't mentioned the pilot bushing in the rear of the crank, is it in good shape ? hav'nt ever done it but they have offset dowel pins for indexing your bellhousing. saw them do it on TV not long ago.to make sure your trans. is inline with the crank...Hope you find a cure!... Jim

tyfyter
Dirt Roller

Total posts: 19
posted August 30, 2004 10:46 PM  
Thanks Jim, Pilot bushing is a roller bushing. I installed when I assembled the motor. I usually inspect the bushing when I'm changing tranys. Traneys go in fairly easy and everything seems to line up. But I will check into the offset dowels.

JohnG
Dirt Maniac

Total posts: 137
posted September 03, 2004 06:50 PM  
driveshaft too short?

do you pull the tranny in tight with the bolts or does it fit correctly then you install the bolts and tighten them?

are you useing bolts that are threaded all the way to the head?

what about lock washers, you need them also.

is your motor straight in your car? though i wouldnt think it would matter.

have you used diff bellhousings etc, from your post it sounds like you have. if one isnt flat, or if the front brg retainter doesnt fit in the hole youll have problems tightening it up for sure.
hanging it should have worked just fine, ive never broken a ear and allways hang saginaws, and have done it on oem alum and a scattershield.

i dont like roller pilots though, theres no need its something else that can fall apart. a solid one is hard to beat.

rxlent
Dirt Full Roller

Total posts: 32
posted September 13, 2004 09:21 PM  
Use a solid, extra long pilot bushing that you can get from anyone who sells racing parts, also try the Lakewood extra long dowel pins and align and torque the bell housing as per the instructions from Lakewood.

Also, make sure you don't pull the tranny up tight to the bellhousing with one bolt. Snug them all evenly and alternately, and then final tighten them. There are different size front bearing retainers so make sure it fits in the bellhousing.

[This message has been edited by rxlent (edited September 20, 2004).]

crew42tx
Dirt Full Roller

Total posts: 53
posted October 05, 2004 11:29 AM  
I would say get an aftermarket scattersheild we have been running saginaws for years with a scattersheild, with and without crossmembers and we have never broken an ear off of our trannys. We have broken many input and output shafts, bearing retainers and chewed the teeth off of some gears, but never broke an ear off. Plus with a mini clutch you should really have a scattersheild anyway.
good luck.

racer17j
Dirt Forum Champ
Total posts: 5390
posted October 05, 2004 06:53 PM  
thats what i was gonna say it would be cheaper and safer in the long run to get a good blow-proofhousing might solve your ear problems too

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