22-09-2020, 12:42 PM
Many thanks Guys for your suggestions. It is getting clear that I will be taking it apart to check things out.
First, I must give a BIG TICK to Terry for his suggestion about the danger of a long bolt. I was convinced that it was not a problem as I backed off all bolts in succession and there was no change to the poor mesh of 1st and Reverse gears. HOWEVER, I was impressed with the photo as it reminded me that there was a recess for the idler gear and so the bolt has to be shorter that I thought. I removed that bolt and bingo- it had been interfering with the idler gear and was now shorter. See photos of the size of bolt initially, the one that has been trimmed by the idler and the type I finally put in it's place. Thinking back, I was having problems with the box completely locking up, but that problem went away. I guess it stopped when I had finally ground off the tip of the bolt, and I was left with a noisy gear set.
By the way, Dave, I had used the old circlip on the replacement bearing, and the laygear float came out as planned.
So I am now left with gears that are a little happier and I have tried adjusting the position of the idler by adjusting the reverse selector. They now go through a cycle of relative quietness to becoming a bit "coggy". Definitely not as smooth as another rubbish gearbox I have.
I washed out the gearbox to flush out the bits of bolt and got a small amount of fine steel dust as expected. However the additional bronze/brass dust and minute filings I also got was a shock. Looking at the selectors there did not seem to be any additional wear to see, and all I can now think of is that I had to stake two of the synchro cones to lock them back in position. Maybe I made cones swell oversize and they are now being trimmed to size.
So it may be that I have three problems to check out and their aftermath.
- oversize bolt - fixed
- possible mismatched or damaged reverse idler- try the old one and check if the new one was damaged when it was in lathe mode.
- synchro cone distortion - inspect.
I also need to clean it all out thoroughly to make sure that bearings etc are clear of any of the bolt shavings. Check that my bolt did not bend the idler shaft or reverse selector.
Then re-build. Electronics seems a lot easier...
First, I must give a BIG TICK to Terry for his suggestion about the danger of a long bolt. I was convinced that it was not a problem as I backed off all bolts in succession and there was no change to the poor mesh of 1st and Reverse gears. HOWEVER, I was impressed with the photo as it reminded me that there was a recess for the idler gear and so the bolt has to be shorter that I thought. I removed that bolt and bingo- it had been interfering with the idler gear and was now shorter. See photos of the size of bolt initially, the one that has been trimmed by the idler and the type I finally put in it's place. Thinking back, I was having problems with the box completely locking up, but that problem went away. I guess it stopped when I had finally ground off the tip of the bolt, and I was left with a noisy gear set.
By the way, Dave, I had used the old circlip on the replacement bearing, and the laygear float came out as planned.
So I am now left with gears that are a little happier and I have tried adjusting the position of the idler by adjusting the reverse selector. They now go through a cycle of relative quietness to becoming a bit "coggy". Definitely not as smooth as another rubbish gearbox I have.
I washed out the gearbox to flush out the bits of bolt and got a small amount of fine steel dust as expected. However the additional bronze/brass dust and minute filings I also got was a shock. Looking at the selectors there did not seem to be any additional wear to see, and all I can now think of is that I had to stake two of the synchro cones to lock them back in position. Maybe I made cones swell oversize and they are now being trimmed to size.
So it may be that I have three problems to check out and their aftermath.
- oversize bolt - fixed
- possible mismatched or damaged reverse idler- try the old one and check if the new one was damaged when it was in lathe mode.
- synchro cone distortion - inspect.
I also need to clean it all out thoroughly to make sure that bearings etc are clear of any of the bolt shavings. Check that my bolt did not bend the idler shaft or reverse selector.
Then re-build. Electronics seems a lot easier...
Slowly rebuilding a '34 RP