Troubleshooting a Hard Shift into First and Reverse Gears

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Jan 31, 2007
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What could be the possible reasons it is hard to shift an H41 into first gear and also hard to shift (with grinding) into reverse gear from a full stop in idle (considering the following)?

When the clutch pedal is depressed during idle, the clutch plate is disengaged and visibly floating/motionless in between the rotating flywheel and pressure plate (video below). This seems to be true when the car is just turned on and also when the car has been driven and the clutch components are warmed up.
From my understanding this means that (1) the pressure plate and master/slave cylinders are doing their job since the clutch plate is disengaging, and (2) the pilot bearing is doing its job since the movement of the input shaft is able to come to a stop even though the crankshaft is rotating.
As soon as I turn the engine off, the gearbox can shift easily into any gear, including first and reverse. Sometime at a full stop in idle it is impossible to get it into first gear and I have to turn the engine off to get the gearbox into gear (if I am unable to get the car to roll slightly to help it get into gear).

If the input shaft is at a stop with the clutch pedal depressed, why would it be hard to shift into first and reverse while stopped and engine idling vs when the engine is turned off?

Sometimes when I am trying to push the gear lever into first gear in idle but it won’t go in at all, I can see the car inching forward very very slightly as I am pushing on the shift lever even though clutch pedal is still held all the way down. Does this mean the clutch disc is prematurely making contact with the flywheel during that very moment and not allowing the input shaft to remain at a stop so that first gear can engage easily?

My clutch and slave cylinders are oem and new, however, I am running the 1200lb pressure plate (vs the 900lb stock) from MarlinCrawler. Could this be a bad combination causing fatigue at the tail end of the fork movement or maybe somehow causing inconsistent fork movement?


 
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Are you assuming the clutch disc and input shaft are at a stop when the clutch is depressed or have you actually verified it?

Syncro's allow the gear to gear shift without grinding, worn syncro's could be an issue. To the best of my knowledge reverse has no syncro's.
 
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Are you assuming the clutch disc and input shaft are at a stop when the clutch is depressed or have you actually verified it?

Syncro's allow the gear to gear shift without grinding, worn syncro's could be an issue. To the best of my knowledge reverse has no syncro's.
I was able to verify it. I have the dust cover off and I can see the clutch disc sitting in the same position between the flywheel and pressure plate and not turning when engine is in idle, when the clutch pedal is pushed in all the way (video added above).

I have not however observed this yet when the shift lever is also being pushed trying to put it into first gear.
 
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I was able to verify it. I have the dust cover off and I can see the clutch disc sitting in the same position between the flywheel and pressure plate and not turning when engine is in idle, when the clutch pedal is pushed in all the way (video added above).

I have not however observed this yet when the shift lever is also being pushed trying to put it into first gear.

I'm sorry but I can't tell from the video you posted. With the engine off have someone depress the clutch and measure the gap between the pressure plate and clutch disc with a feeler gauge. If the hydraulics are working there should be a measurable gap. Check it at various positions as if one or the 3 levers or part of the diaphragm are slightly out of adjustment it could be applying pressure to the disc. If the disc is spinning then getting it to shift into reverse without grinding is unlikely, good syncro's should allow shifting into first.
 
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I'm sorry but I can't tell from the video you posted. With the engine off have someone depress the clutch and measure the gap between the pressure plate and clutch disc with a feeler gauge. If the hydraulics are working there should be a measurable gap. Check it at various positions as if one or the 3 levers or part of the diaphragm are slightly out of adjustment it could be applying pressure to the disc. If the disc is spinning then getting it to shift into reverse without grinding is unlikely, good syncro's should allow shifting into first.
Thanks, I went ahead and checked and measured that the clutch disc has at least a 2mm gap (between the flywheel/pressure plate) to float and I can rotate it very freely in neural when the clutch is depressed. Was also able to test again and verify that that the disc is at a dead stop in idle with pedal depressed and car idling.

It’s little hard to see in the video above but in the first few seconds of the clip it shows the input shaft at a stop and then the last several sections, the clutch disc is sitting still in the same position.
 
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I could very well be wrong; but I don’t see your input shaft or clutch stopped.
The only way the vehicle would try to move forward at idle or speed is if the engines rotation was moving the transmissions gears via input. I think what you are seeing at the beginning of the video as the input shaft being stationary, is actually the bearing retaining housing, which is always fixed and doesn’t move. I can’t tell from the video if the clutch is moving or not, but guessing it is. So assuming that’s right and stuff is moving, something needs further adjustment to disengage, or the input bearing is toast or too tight and spinning the input shaft at all times.
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SlapSmak

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are you saying the clutch disk is stationary because of you see it through the gaps in the pressure plate while the flywheel is spinning?
you do realize that that creates a slideshow effect similar to the first film projectors? it appears stationary because it is moving at the same rate as the flywheel and you see it for a split second?

and like @Skreddy said, your looking at the housing collar that the input shaft rides in. it never moves.
 
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are you saying the clutch disk is stationary because of you see it through the gaps in the pressure plate while the flywheel is spinning?
you do realize that that creates a slideshow effect similar to the first film projectors? it appears stationary because it is moving at the same rate as the flywheel and you see it for a split second?

and like @Skreddy said, your looking at the housing collar that the input shaft rides in. it never moves.

Thank you both for helping me see that. I see now that I was looking at the housing collar, and that the input shaft is not visible. However, I took another hard look at the clutch disc and inserted a small piece of an orange zip tie between the mating surfaces of disc (fitted very very loosely) and when idling in neutral it really looks like the disc is at a standstill. I added a second video above to show.
 

SlapSmak

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I would agree that the orange zip tie is not moving, so no idea. Obviously rotation is being transferred to transmission even with clutch pedal depressed as you can shift when engine is off. Bad throw out maybe?
 
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Everything slapsmak said. What’s weird to me is I've never seen a clutch disc sit that still when idling in neutral with clutch pedal depressed. They always seem to spin at least 1 rpm or so. If it’s hard to get in gear, somewhere in the chain engine rotation is still being transferred to the transmission; input bearing, clutch not disengaging, throw out bearing. I know that’s not that helpful, just thinking out loud.
 
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Not a master technician but I very recently had the same problem. The Clutch pedal had a LOT of pre-travel before you felt resistance. There actually is a spec in the manual for how far this travel should be. I adjusted the clutch master cylinder out by turning the clutch rod (there are 2 flats on the rod) until I had only a short distance before I felt resistance on the pedal.

But there ended up being 1 more thing: I was pushing the pedal in by hand-literally-while I was adjusting the clutch master cylinder rod to take up excess travel, and I saw that the inside boot for the cylinder was leaking into the cab every time I pressed the clutch. I priced a rebuild kit but I think the firewall boot wasn't available. SOR said it had picked up new clutch master cylinders from a company that had made the originals. It does look like the OEM part. Nothing is cheap on a Cruiser but this was one of the cheapest options for replacing the entire upper unit and it looked like the original and replacing the clutch master and adjusting the new cylinder to have the proper play seems to have solved my shifting problems and the leak of hydraulic (brake) fluid into the cab. By the way, that stuff eats paint pretty quickly. I cleaned it up, treated the surface the fluid had touched and repainted it black. That also started me looking at a new one piece front mat but I have a heater I need to finish before winter so that will have to wait.
 

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