Replacing the Bell Housing

[Baconaire]

I just replaced the flywheel, cluch pad, release plate, throwout arm, and throwout bearing. The actual replacement of these part was real easy. However I am having the darnest time sliding the transmission back onto the crankcase. I don't know if its a problem lining up the trans input shaft splines with the clutch splines, but the input shaft turns relatively freely.

I am in the driveway on jack stands. I'm using a motorcycle jack to jack the trans and am jacking the engine from the oil pan. I am clearing the brace that is directly under. I resorted to trying a level to make sure the pilot bearing, clutch splines and input shaft are about the same angle.

The case bolts a M12 1.50 pitch. I could only get 1.25 pitch so I cut the heads of those, and tried to use them as studs, to no avail. I am looking for new bolts to do the same with the proper pitched bolts.

I thought this morning I should also double check I have the right part/spline patern on the cluth plate. I thought I test fit it but maybe I didn't. I've spent about 6 hours on my back trying to get this baby back together. Does anyone have the part # for the Sachs clutch plate or kit.

I any event, does anyone have any tips. It should slide on pretty smoothly right? It should not require force?

[Tool Pants]

I have replaced clutches on several cars over the years, on my driveway, but not yet on a Boxster. I know what you are saying, and I do not envy you doing this with the car on stands and you on your back. Either the transmission went in first time, or I played around for hours geting the input shaft to line up with the splines, or jacked up or down the engine and or transmission to get them on the same plane.

I take it you used an alignment tool for the disc. Count the splines on the old and new disc to make sure. Maybe turn the input shaft just a hair. The transmission on any car is going to slide right in if the Karma is right.

The worse clutch I replaced was on my Triumph GT6. You removed the transmission from the inside of the car. You had to take the seats and some interior parts out of the car. First time I forgot to put in the release bearing. Found out when I started the car and pushed down on the clutch - no clutch. Start all over again. Could not use a transmission jack on that car.

Then a friend with a Sprite replaced his clutch, and it would not release. He put the disc in backwards.

[topmech0]

The trans should slide straight on with no real problems. I find best way is to put the trans in to any gear and if no luck then slowly turn half shaft flanges as you push toward motor. There maybe a possibility that you have slightly moved the centre disc of clutch as you have been struggling. I would remove clutch,check the centre disc on the trans input shaft(to check correct fitting), then using clutch aligning tool refit clutch to flywheel and try again. Good luck and hope you have a buddy to help as its so much easier with two pairs of hands.

Edited May 2, 2008 by Loren
Removed ALL CAPS - please do not post in ALL CAPS

[kbrandsma]

Make sure you cleaned the teeth of the drive shaft. The manual also says to apply a thin coat of grease to the shaft. (Olista Longtime 3 EP or equivalent.) I used a synthetic high temperature grease and the transmission went effortlessly in.

Did you remove the dual mass flywheel (DMF) and if so have you removed anything that was used to hold the DMF stationary while you torqued the bolts.I'm just trying to think what else might be getting in the way.

[Baconaire]

Reporting back with success! I must have wasted 8 hours fighting and fussing just getting the trans back on. Here are some tips:

Use old case bolts or buy M12 1.50 pitch, at least 100ml long. Cut the heads off, round them off. Then thread them into the case as guide studs. Be sure they are long enough that you can get them out after. Replace each one, one at a time with a proper case bolt.

I thought at one point I might have the wrong clutch disk. So I disassemebled the clutch and slid it on the spline of the input shaft (do this before installing). It was a tight fit, but was the right one! I used a file on the clutch disk on the side that would be first mating with the input shaft and gently opened up the mating splines on the clutch disc. Make sure the metal is smooth, sand if needed. (File the clutch disk spline, not the input shaft! I believe this will have zero adverse effect on the the whole assembly as installation it the only time that front part of the clutch spline is important. Once its one the two mate in full.) Grease splines and clutch disc splines. Also make sure you are in a gear that you can move the input shaft easily. It felt like neutral or 5th.

Yes use a clutch aligment tool. And of course lube the splines but lightly. And be mindful of trying to keep the engine and trans at compatible angles.

If your car is older or in the rust belt, factor in time for rusted/broken bolts. I had problems with getting the bell housing open, then trouble getting it back together. Two different sets of issues. Next time I will be a factore of 10 faster.

Good luck!