Engine harder to turn as I tighten up gearbox bolts.

Comfortably Numb · 12th May 2019, 17:51

Having changed the clutch on my CDT, using the clutch alignment method I have always succeeded with, namely, a piece of 15mm copper pipe with electrical tape wrapped around it, and using a threaded bar in the top, rearmost bolt-hole in the engine to 'hang' the gearbox on, and using 2 trolley jacks and a scissor jack to get the gearbox level and onto it, I was able to get the gearbox within 18mm of the engine face on 2 bolts and the stud, with only light spannering. Using a screwdriver through one of the notches in the bottom of the bell-housing, and in gear, I could turn the engine, and see the drive shafts turning. However, with a couple more turns on each of the bolts and stud nut, they became much harder to turn, and so did the engine.When I slackened the bolts (near the bottom of the gearbox) but not the nut at the top, the gearbox started to move away from the engine, and it again became easier to turn the engine. I should add that by now, I had only one jack - supporting the engine. I have used slightly longer bolts to get to this stage, as the proper ones will not yet reach their threaded holes. Nothing is trapped in the gap. What have I done wrong? Is marginal mis-alignment of the clutch causing this difficulty? If the input shaft has made its way through the clutch centre, is it possible that it can't get into the flywheel bearing? If I reconnect the clutch slave, and press the pedal at this stage, will it release the driven plate and allow it to centre itself?

12th May 2019, 17:51	#1
Comfortably Numb Posted a thing or two Rover 75 Saloon Join Date: Dec 2017 Location: Penrith Posts: 1,336 Thanks: 165 Thanked 303 Times in 241 Posts	Engine harder to turn as I tighten up gearbox bolts. Having changed the clutch on my CDT, using the clutch alignment method I have always succeeded with, namely, a piece of 15mm copper pipe with electrical tape wrapped around it, and using a threaded bar in the top, rearmost bolt-hole in the engine to 'hang' the gearbox on, and using 2 trolley jacks and a scissor jack to get the gearbox level and onto it, I was able to get the gearbox within 18mm of the engine face on 2 bolts and the stud, with only light spannering. Using a screwdriver through one of the notches in the bottom of the bell-housing, and in gear, I could turn the engine, and see the drive shafts turning. However, with a couple more turns on each of the bolts and stud nut, they became much harder to turn, and so did the engine.When I slackened the bolts (near the bottom of the gearbox) but not the nut at the top, the gearbox started to move away from the engine, and it again became easier to turn the engine. I should add that by now, I had only one jack - supporting the engine. I have used slightly longer bolts to get to this stage, as the proper ones will not yet reach their threaded holes. Nothing is trapped in the gap. What have I done wrong? Is marginal mis-alignment of the clutch causing this difficulty? If the input shaft has made its way through the clutch centre, is it possible that it can't get into the flywheel bearing? If I reconnect the clutch slave, and press the pedal at this stage, will it release the driven plate and allow it to centre itself?