After replacing the pinion and setting up the rear diff, replacing the transfer case with a NOS transfer case I have a very quite vehicle apart from the exact same grinding noise at 48Kph at 2400 revs.
Have traced it to the gearbox I think
any Humber owner will know the total Pain in the A... it is to get the transmission out. Well I have had mine out and stripped down twice and I am a bit of a master at it. Up and out through the passenger door. Have found that "Fred the Fiddler" some time in the past has been at it and have found the following
1. Stepped pin that holds the 2nd and 3rd gear selector ring in place missing hence trapped 5 k's out of town in third gear travelling at 10Kph home as it slid past its guides.
2. Rear main shaft thrust washer missing.
3. Reverse idler 1/4 inch thrust washer missing
After finding all of this I thought I had it, but no the dreaded noise was still there.
So out the box came again, stripped down and replaced the cluster shaft as the brass bushes seemed a little worn and thought that maybe the nose was tooth chatter due to inconsistent messing, fitted it all up, passed, the cigarette paper through the gears and it came out crinkled but not torn so I was "In like Flynn". At least I had false hope it would seem. (Richard Couttes-Smith shared that little trick with me).
But no, the noise was just the same except the vehicle was even smoother on the road until the noise starts. A phone call to Russell in Stawell and I will pick up another gear box complete to install and see if the noise disappears. if it doesn't I will at least know that my gearbox is OK, if this occurs damned if I know what is causing the noise. I will know in about two weeks.
Some pictures of my parts gearbox stripped down. Built like a brick shithouse and as heavy as can be.
The maddening part about this saga is that upon a visual inspection on rebuild the gearbox looked and felt fine, did not drive the vehicle so could not test it out. Oh well the joys of vehicle restoration and wanting to get it right.
Cheers,
Dave.