Hello, I am a newbie to the site. I live in south suburbs near Chicago. I have a 34 Ford street rod I am building. It has a five speed Tremec transmission. The bell housing needs to be dial indicated to check runout. I was wondering if anyone has any contacts in the area that I could hire to help complete this task. It is a two man job as the motor in in the car. I have a lift in my garage so easy access.
Dial Indicate Bell Housing
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Aren't there dowel pins in the block? Are you using an adapter or aftermarket bellhousing? What engine?
It would be cheaper to just go to Harbor Freight and buy an indicator and magnetic base. Just stick it on the crank or flywheel, place the indicator feeler on the pilot opening of the bellhousing and zero it out. Rotate the engine, any variance in the reading is your runout.
It would be cheaper to just go to Harbor Freight and buy an indicator and magnetic base. Just stick it on the crank or flywheel, place the indicator feeler on the pilot opening of the bellhousing and zero it out. Rotate the engine, any variance in the reading is your runout.
Thanks for your reply, yes there are dowel pins in the block, they are Lakewood "EZ-Adjustable Bellhousing Dowel Pins" #15907. I have a Lakewood Quick Time Safety Bell Housing on a SBC 383 (Gen 1).
Purchasing an indicator and magnetic base is not an issue. The issue is in order to rotate the crank it has to be done from the front of the motor and so becomes a two man job, one person to watch the indicator and one to strong arm the crank. If there is an adjustment to be made, I would need to know which quadrant on the bellhousing it lies within so a proper adjustment can be made.
Yep, I may end up having to do that if I can't get an assistant. Thanks
Rotating the engine introduces crankshaft endplay and crankshaft end runout. The only way to measure bellhousing runout is to rotate the dial indicator around the bellhousing mating surface from a fixed flywheel point.
I interpreted runout as whether the block surface and trans surface were parallel rather than concentricity of the crankshaft centerline and the bellhousing mating centerline. The question I should have asked is what led him to have concern about his Lakewood bellhousing. If what his concern is concentricity then you are correct.
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I will come help you, but I'm pretty far away!
Thank you for the offer, but yes you are far away. I was thinking somebody more local.
Long story short....on this build the Tremec 600 is new and on shakedown run (4 miles) after returning home clutch wouldn’t engage. So tore it all down and discovered throw out bearing was compromised and the front bearing retainer was cracked and had to be replaced. Fortunately shaft on tranny was spared. Not 100% sure what caused it, but I believe the pilot bearing may have been damaged on installation thus misaligned. New pilot bearing, new input shaft retainer and throw out bearing have been replaced. Tolerances on the Tremec are tight so want to make sure all within specs to avoid a repeat. I think centerline concentricity is my concern. Do you agree? Tim
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Ouch, that looks like a product of assembly, although the bluing happened during use. Broken snouts that I have seen, are usually at the base of the housing, right where it narrows. You are correct, the Tremecs have tightened up tolerances, and better bearings, to combat mainshaft deflection. This wasn't an issue with old 4 speeds, but the more gears, the longer the space between the front and center bearing. This increases deflection in the mainshaft placing load on the input shaft pocket bearing.
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As a rep for a manual transmission that uses ball bearings, in 700hp plus applications? Concentricity between the rear bellhousing bore and the crank bore is important. Its also, not always the bellhousings fault, but the bellhousing is the part that we can manipulate to correct the misalignment.
More often than not; line-boring the mains, aftermarket cranks, block casting core shift and general grunge/paint/scrapes and knicks are the worst offenders.
Incidentally; tapered bearing sets are finicky creatures; that have this weird feature of wanting to squeeze the oilfilm out of the bearing at high RPMs, and don't tolerate misalignment.
I have to coach new customers on bellhousing alignment almost daily. Old school 4 speeds will exhbit 4th gear jumpout, cracked front retainers, cracked clutch forks, throwout bearings that wipe out in a few thousand miles, and increased shift effort at high rpms. We saw less of it back in the day, because most of us didnt understand it at the time, although we recognized the symptoms; and the vast majority of us couldnt afford the type of hosspower that would really show the problem. We would also consider stickshifts as disposable and if it didnt shift right; simply go get another one.
The video I use most often is here:
(232) Part 17 How To Align The Bellhousing Using Offset Dowel Pins For The Big Block Chevy - YouTube
The offset pins I use for GM apps are here:
RobbMcPerformance Bellhousing Alignment Dowels
You should also raise the dial indicator out of the bellhousing bore and traverse the back face of the bellhousing to check for parallelism AFTER your concentricity check. The back face of the bell should be within 0.002 parallel to the flywheel. If you need to traverse any holes? Cover them with smooth packing tape stretched tight.
You need to be within 0.005 of concentric according to most Tremec literature. I have customers in Beloit and similar. But theyre shops who probably won't let you help.
Let me know if you still need help!
N
More often than not; line-boring the mains, aftermarket cranks, block casting core shift and general grunge/paint/scrapes and knicks are the worst offenders.
Incidentally; tapered bearing sets are finicky creatures; that have this weird feature of wanting to squeeze the oilfilm out of the bearing at high RPMs, and don't tolerate misalignment.
I have to coach new customers on bellhousing alignment almost daily. Old school 4 speeds will exhbit 4th gear jumpout, cracked front retainers, cracked clutch forks, throwout bearings that wipe out in a few thousand miles, and increased shift effort at high rpms. We saw less of it back in the day, because most of us didnt understand it at the time, although we recognized the symptoms; and the vast majority of us couldnt afford the type of hosspower that would really show the problem. We would also consider stickshifts as disposable and if it didnt shift right; simply go get another one.
The video I use most often is here:
(232) Part 17 How To Align The Bellhousing Using Offset Dowel Pins For The Big Block Chevy - YouTube
The offset pins I use for GM apps are here:
RobbMcPerformance Bellhousing Alignment Dowels
You should also raise the dial indicator out of the bellhousing bore and traverse the back face of the bellhousing to check for parallelism AFTER your concentricity check. The back face of the bell should be within 0.002 parallel to the flywheel. If you need to traverse any holes? Cover them with smooth packing tape stretched tight.
You need to be within 0.005 of concentric according to most Tremec literature. I have customers in Beloit and similar. But theyre shops who probably won't let you help.
Let me know if you still need help!
N
Thank you for the information. I ordered the dowels from RobbMc as this should enable me to align bellhousing, remove and install clutch, pressure plate without changing alignment. With the current Lakewood dowels my concern was when removing bellhousing to finish installation of internals, it would be knocked out of alignment. I am going to give these a try and I will report back. Thanks for the offer of help, I will keep you posted. Tim
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I noticed in your reply to MGK that you were using the more common ratchet-on-the-balancer method. Thats great to work on things at the front of the motor.
However, buy this and you don't need to do all the back and forth
Lisle Tools 23800: Flywheel/Flexplate Tool | JEGS
Normally Id recommend the 15 dollar version (half price) BUT, if that tool doesn't work for you, you'll have more downtime and buying a replacement tool. Buy the Lisle. Or see if your local autoparts store has a rental/loaner.
However, buy this and you don't need to do all the back and forth
Lisle Tools 23800: Flywheel/Flexplate Tool | JEGS
Normally Id recommend the 15 dollar version (half price) BUT, if that tool doesn't work for you, you'll have more downtime and buying a replacement tool. Buy the Lisle. Or see if your local autoparts store has a rental/loaner.
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