Problem after fitting new gearbox
Discussion
I am currently in the process of building up a Mitsubishi Colt Gti for track use, part of that process was fitting a gearbox from a Cyborg model with the factory LSD. After a few problems with the driveshaft, which I got sorted last night, I stumbled across another major problem!
Along with the gearbox, a new clutch and a lighter flywheel were fitted (the flywheel is a standard Mitsubishi item off of another car, it hasnt been machined down).
After getting the hub nut back on after the thread got damaged, I thought I better start it up to see if everything had been bolted back up correctly.
Click - nothing, the ignition is on and the starter is trying to engage but wont turn the engine over.
It turned over fine before the gearbox was installed, both by hand on the crank pulley and via the starter motor / running.
Took the starter off as thought the sprocket was not quite aligned with the teeth on the flywheel and then tried the ignition to see if the starter is working, few sparks flew but the starter is working.
Tried turning the engine over without the starter on it with a rachet on the crank pulley, wont turn over.
Loosened the spark plugs off - still wont turn over, dipped the clutch - still wont turn over!
A mate thinks the bolts for the new lighter flywheel maybe too long and are catching inside the block? But Im sure we turned the egnine over on the crank pulley to try and get the gearbox back on and aligned.
It was quite hard to get the gearbox onto the engine, maybe the spline isnt in the clutch but I dont think its that?
So the gearbox will have to come off again for an investigation this weekend and it will be a process of elimination. Take gearbox off - see if engine turns over. If it does then the old box is going back on. If it doesnt Ill take the flywheel off, if it turns over then, the old flywheel is going back on. If it still wont turn over, looks like its rebuild time, but I cant understand if the engine is seized as it was running perfectly last week.
The track day is two weeks away now! Argh! Bloody cars!
Anyone got any ideas?
Along with the gearbox, a new clutch and a lighter flywheel were fitted (the flywheel is a standard Mitsubishi item off of another car, it hasnt been machined down).
After getting the hub nut back on after the thread got damaged, I thought I better start it up to see if everything had been bolted back up correctly.
Click - nothing, the ignition is on and the starter is trying to engage but wont turn the engine over.
It turned over fine before the gearbox was installed, both by hand on the crank pulley and via the starter motor / running.
Took the starter off as thought the sprocket was not quite aligned with the teeth on the flywheel and then tried the ignition to see if the starter is working, few sparks flew but the starter is working.
Tried turning the engine over without the starter on it with a rachet on the crank pulley, wont turn over.
Loosened the spark plugs off - still wont turn over, dipped the clutch - still wont turn over!
A mate thinks the bolts for the new lighter flywheel maybe too long and are catching inside the block? But Im sure we turned the egnine over on the crank pulley to try and get the gearbox back on and aligned.
It was quite hard to get the gearbox onto the engine, maybe the spline isnt in the clutch but I dont think its that?
So the gearbox will have to come off again for an investigation this weekend and it will be a process of elimination. Take gearbox off - see if engine turns over. If it does then the old box is going back on. If it doesnt Ill take the flywheel off, if it turns over then, the old flywheel is going back on. If it still wont turn over, looks like its rebuild time, but I cant understand if the engine is seized as it was running perfectly last week.
The track day is two weeks away now! Argh! Bloody cars!
Anyone got any ideas?
If the gearbox is bolted up, then the either the splines have engaged properly, or you have already destroyed the friction plate. If the engine turned over ok before you fitted the gearbox, the logical conclusion is that you have some clearance issue between the gearbox and the clutch assembly, which would also tie in with the difficulty you had mounting the gearbox on the engine.
Mr2Mike said:
If the gearbox is bolted up, then the either the splines have engaged properly, or you have already destroyed the friction plate. If the engine turned over ok before you fitted the gearbox, the logical conclusion is that you have some clearance issue between the gearbox and the clutch assembly, which would also tie in with the difficulty you had mounting the gearbox on the engine.
I guess all will be revealed when we split the box off again.Cheers.
Matt_N said:
Clutch is working, well as far as I can tell, the slave cylinder is moving the fork.
You could also confirm that it is actually releasing, by trying to turn the output shaft with the clutch pedal down. (Not sure what that would tell you, but if it won't release that's more evidence to think about.)Took the cambelt cover off today and it looks like the cambelt has jumped a tooth on one of the pulleys, a guy from the Colt owners site that that could have been a possibility, so hopefully it will be alright after I re-time.
Not sure how the cambelt has jumped a tooth though, will give the cambelt a thorough going over to look for any damage and check the tensioner and over bits for signs of damage.
Not sure how the cambelt has jumped a tooth though, will give the cambelt a thorough going over to look for any damage and check the tensioner and over bits for signs of damage.
Im a right numpty!
Took the box off, the clutch plate was in the wrong way, ie the gearbox side was facing the flywheel. This didnt help when it came to trying to get the shaft into the clutch.
Also the flywheel is very tight in the box, so I put the old flywheel back on.
But, tried to get the box back on and it just wont align, it did at one point, but as soon as I tried to pinch the bolts up, it went out of line again.
Im not using a clutch alignment tool, which I think is half the problem, a mate has one but hasnt been around, he is around this week, so will have another go. If not the engine is coming out and will do it like that.
Took the box off, the clutch plate was in the wrong way, ie the gearbox side was facing the flywheel. This didnt help when it came to trying to get the shaft into the clutch.
Also the flywheel is very tight in the box, so I put the old flywheel back on.
But, tried to get the box back on and it just wont align, it did at one point, but as soon as I tried to pinch the bolts up, it went out of line again.
Im not using a clutch alignment tool, which I think is half the problem, a mate has one but hasnt been around, he is around this week, so will have another go. If not the engine is coming out and will do it like that.
Matt_N said:
Im not using a clutch alignment tool, which I think is half the problem, a mate has one but hasnt been around, he is around this week, so will have another go. If not the engine is coming out and will do it like that.
Try putting a snug fitting deep socket into the the splined part of the clutch plate, it makes judging the centering of the plate relative to the clutch fingers much easier.Well its finally on and working after spending all of Saturday investigating.
The culprit was found to be the thrust / release bearing. The central ring was slightly off centred in the bearing. Hard to believe something so small can affect it so much.
All bolted back up, driveshafts in and timed up ready to go.
The culprit was found to be the thrust / release bearing. The central ring was slightly off centred in the bearing. Hard to believe something so small can affect it so much.
All bolted back up, driveshafts in and timed up ready to go.
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