This is what i meantI think Sacrifice was stating that you shouldn't use longer bolts to draw the transmission in on the alignment dowels. Point being, if you can't get the transmission in far enough that the stock bolts can be started and then used to draw it onto the dowels it isn't in far enough and something is out of alignment, most likely the input shaft isn't yet started properly into the pilot bearing. If you were to use longer bolts to draw it in you could damage something. And I also suspect the longer bolts would bottom out before the trans is fully bolted to the bellhousing.
Trans Alignment Woes
Am I missing something?
Brand new Tilton ST-246 install. Ram 03-013 alignment tool. Cannot for the life of me get the transmission to seat the last 1/4"-3/8". Slides in real easy through the splines, just can't seat the pilot bearing. Seems like everything is a touch low.
Alignment tool measures 0.585. Trans measures 0.589. Pilot bearing measures about 0.591-0.592. Seems like my brand new alignment tool is undersized? Assuming that gravity pulls the tool to the bottom of the bore, I've got about 2.5 thousands of interference between the pilot and the input. And with the twin disk I've got considerably more spline area and clamping force stopping it from self aligning.
I've tried reseating the clutch 6 times so far. 9hrs on my back under the car stopped being fun about 7hrs ago.
-Brian
Brand new Tilton ST-246 install. Ram 03-013 alignment tool. Cannot for the life of me get the transmission to seat the last 1/4"-3/8". Slides in real easy through the splines, just can't seat the pilot bearing. Seems like everything is a touch low.
Alignment tool measures 0.585. Trans measures 0.589. Pilot bearing measures about 0.591-0.592. Seems like my brand new alignment tool is undersized? Assuming that gravity pulls the tool to the bottom of the bore, I've got about 2.5 thousands of interference between the pilot and the input. And with the twin disk I've got considerably more spline area and clamping force stopping it from self aligning.
I've tried reseating the clutch 6 times so far. 9hrs on my back under the car stopped being fun about 7hrs ago.
-Brian
21 - 40 of 43 Posts
This is what i meant
Ok, wasn’t sure since I thought I was the only one that made a mention of longer bolts.This is what i meant
I believe I may need to buy off set dowels.
I took a step back and measured concentrity. I believe the bellhousing is about 8 thousands low. Half the distance between of the total of the two furthest apart measurements right?
0* = 0.000
45* = 0.000
90* = 0.006
135* = 0.011
180* = 0.016
225* = 0.015
270* = 0.009
315* = 0.001
I subtracted 0.90 from all my values from the raw data in the photo. Values with a zero at the front had gone all the way around.
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Did this after I measured enough depths to determine the input was starting to seat in the pilot so why wouldn't the dowels even be close to seating.
-Brian
I took a step back and measured concentrity. I believe the bellhousing is about 8 thousands low. Half the distance between of the total of the two furthest apart measurements right?
0* = 0.000
45* = 0.000
90* = 0.006
135* = 0.011
180* = 0.016
225* = 0.015
270* = 0.009
315* = 0.001
I subtracted 0.90 from all my values from the raw data in the photo. Values with a zero at the front had gone all the way around.
Did this after I measured enough depths to determine the input was starting to seat in the pilot so why wouldn't the dowels even be close to seating.
-Brian
I'm assuming the engine, bellhousing and transmission are all the same parts that were together when you started the clutch replacement. If so, the only thing different now is the clutch. So the only thing that could be throwing the alignment off is anything that is new to the equation, IE: the clutch, flywheel and pilot bearing.
Maybe a dumb question but does your transmission input shaft have excessive play in it? I could see if being an issue installing if it has enough slop to droop down when trying to install.
i believe OP is overthinking it.
i mean, it was bolted up to begin with. it should go back together.
maybe OP should unbolt the bellhousing from the trans and then bolt it to the engine.
then install the trans.
might find it easier to line up.
maybe OP should unbolt the bellhousing from the trans and then bolt it to the engine.
then install the trans.
might find it easier to line up.
Well that's a good question, which way are the attempts being made? Is the OP bolting the bell to the trans and then trying to attach it to the engine or has he bolted the bell to the engine and is trying to attach the trans to the bell?i mean, it was bolted up to begin with. it should go back together.
maybe OP should unbolt the bellhousing from the trans and then bolt it to the engine.
then install the trans.
might find it easier to line up.
Contrary to what the shop manual states, I've always found it easier to bolt the bell to the engine and then bolt the trans to the bell.
I always do the bell housing separate, don’t wonna bleed the system again and makes it’s a little easier running a trans and shifter not made for the application.
Doing them together would be a pain in the ass
Agreed. But for whatever reason that's what the shop manual shows, to attach the bell to the trans first and then attach it to the engine. At the very least that would make it difficult to see if the input shaft is lining up with the clutch disc.Doing them together would be a pain in the ass
I'm an engineer by trade so I probably am over thinking it. I didn't have the tools for measuring this when I last installed this engine/transmission combo. I am bolting the bell to the engine and then trying to align and install the transmission. For ~$40 I bought 0.007" offset dowels from RobbMC and get it nearly dead on so I'll do it. I've spent this much on it, might as well do it right. My C-10 ended up with 0.014" dowels when I put that together, and it took almost no force to seat it all the way. I also have plenty of other vehicles to drive for the time being so I can wait.
-Brian
-Brian
You are not overthinking but thinking in the wrong direction. Follow Tri powe'rs logic in that you must be installing it incorrectly since the bell housing lined up before. So, what I would try next is to get an alignment tool to make sure the friction disc is centered. Loosen all of the pressure plate bolts so that the friction disc moves around. Then insert the alignment tool, making sure it is in the pilot bushing fully. Then tighten the bolts to specs and bolt on the bellhousing. Get the right angle on the trans and if you have a yoke, put it on the splines so you can turn the input shaft and it should wiggle in. Place the trans in any gear to wiggle the input shaft.
If it is still off, there is something wrong with the clutch assembly. Hope this helps.
If it is still off, there is something wrong with the clutch assembly. Hope this helps.
um, read his posts broham. he's using a billet clutch alignment tool.
Yeah, but it may not of come with the kit. Luks provides a plastic aligment tool with the kit. If the tool is Ok, then there is something wrong with clutch or installer.um, read his posts broham. he's using a billet clutch alignment tool.
I had to use a pry bar to get it apart, that suggests my original combo was probably not perfectly lined up either.
I measured the tool that came with the kit. The pilot the cheap tool is not round and anywhere from 0.580 to 0.584 in diameter. Also the splines have a loose fit. The billet tool is a consistent 0.585 all the way around and the splines have far less play. The actual trans pilot is 0.589 and round. I believe the spec is 0.590.
Offset pins might be here as early as tomorrow. I'll measure again and see where it falls then. Having spent nearly $2k on the Tilton set up versus the $200 for the original Luk, another $50 to do it right is not a big deal. Especially behind the 6.7L stroker.
-Brian
I measured the tool that came with the kit. The pilot the cheap tool is not round and anywhere from 0.580 to 0.584 in diameter. Also the splines have a loose fit. The billet tool is a consistent 0.585 all the way around and the splines have far less play. The actual trans pilot is 0.589 and round. I believe the spec is 0.590.
Offset pins might be here as early as tomorrow. I'll measure again and see where it falls then. Having spent nearly $2k on the Tilton set up versus the $200 for the original Luk, another $50 to do it right is not a big deal. Especially behind the 6.7L stroker.
-Brian
No, that means the alignment dowels have a tight fit (like they should).I had to use a pry bar to get it apart, that suggests my original combo was probably not perfectly lined up either.
yup.No, that means the alignment dowels have a tight fit (like they should).
every time i've done it, i've needed to work at getting it seperated.
using offset dowels is the wrong answer. do not pass go.
find out the real reason you can't get it in. the answer is likely very simple, you are just disregarding it.
find out the real reason you can't get it in. the answer is likely very simple, you are just disregarding it.
I spent multiple hours separating my trans and bell housing from their respective dowels. They get seized in there.No, that means the alignment dowels have a tight fit (like they should).
Putting it back together was not the same issue. I took some light sand paper to them to clean of any rust and used antiseize
21 - 40 of 43 Posts
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