Summer shade tree repair


#1

Why can’t I get my transmission back in. 84 GMC 1 ton with HD four speed. Replaced clutch and now I can not get the trans back on the bell housing. I have two dowels in lower holes seems to be binding when input shaft enters the disk. My old mopars just slid in of course they were not as big as the truck . Thanks all


#2

Did you use a clutch alignment tool to line the clutch disc up before tightening the pressure plate bolts?
Did you check the clutch disc to make sure that it would slide easily on the splines before installing it on the flywheel?


#3

Tried both. I am thinking that the alignment is off caused by pulling the jack back to get the bell housing off and to replace the cover and disk. I am thing of trying four dowels to make sure it is square. Will have to grind off a mounting boss which is not used on this application to have clearance for one. This is the first diaphragm clutch I have done. On the old Borg and Beck on my mopars I used wood shims to hold the pressure plate back so the disk floated in the clutch cover during install can’t figure how to do it with all the fingers.


#4

The only two items I can think of is { does the cluch have the same number of grooves} could the through out bearing be out of place.


#5

I haven’t done a clutch job is almost 20 years…but whenever I did…the first thing I’d do was make sure the clutch fits on the transmission shaft. I got burned that way once…one of my first clutch jobs. It was on my 73 Vega. I had the same problem you have…after almost 5 hours of messing with it…out of despiration I unbolted the preasure plate and removed the clutch and tried to fit the clutch on the trany shaft…it wouldn’t fit. The parts deparment sold me the WRONG part. And since this was now Sunday…they were closed and I had to wait until monday to get it exchanged…A royal pain in the butt.


#6

I asked at the City garage. Told me to make four head bolts 6 inches long to guide the trans in. As it slides in I had to cut off one bolt to clear. seems this gear box will not balance on a transmission jack and gets out of alignment unless you use the long pins. thanks to all


#7

Mike is exactly right about always making sure the disc fits the transmission mainshaft.

On the older Subarus it was generally easier to pull the engine rather than the transmission on a clutch job, especially on non-A/C equipped ones.

I did one and that engine would not stab back in no matter what. After wasted time and learning some new profane words, I hoisted the engine back out, removed the disc, and found the disc would not fit although visually and by the parts number it should have been the right one.

Found out the disc would fit fine IF a certain spline on the disc and shaft were aligned just right. Move it one spline either way and it could not even be forced on.
A few matchmarks, delicate movement, and it stabbed right in.

No idea what the deal was on this one as the trans and disc splines looked fine and neither the disc or shaft has a “missing spline” like one might find on a steeing column shaft.