meadowfield 2,595 #1 Posted January 6, 2014 (edited) Hi all, project C4 is 99% finished and I took it out for a spin on sunday. I'm not sure whether it was doing it before, but after my party trick of wall driving I'm now hearing some pretty grim noises from the tranny. The sound is like half engaged gears/rattling when driving. I'm hoping its nothing serious as I wasn't planning a strip down. Does it sound perhaps like a bearing? I'm taking the drive for the front wheels from the brake drum, is that bearing prone to failure? mark Edited January 6, 2014 by meadowfield Share this post Link to post Share on other sites
AMC RULES 37,134 #2 Posted January 6, 2014 Sorry to hear... hope it an easy fix for you Mark. Share this post Link to post Share on other sites
953 nut 55,860 #3 Posted January 7, 2014 Sorry to hear of your bad fortune, With the out drive sprocket being mounted outside the brake drum you probably put a lot of extra load on the bearings. May need to fabricate an outer bracket with a pillow block to share the load. With all you have done I know you can overcome this. Good luck. 2 Share this post Link to post Share on other sites
groundhog47 347 #4 Posted January 7, 2014 (edited) Mark, Have seen your good work but I didn't notice whether that was an 8 speed trans or not. If so the brake shaft if wallows the bearing out (3/4"id needle), would either pull the gear group closer or farther. But it's also possible the extra force from front bind caused a slip or crack/break of some teeth. If i'm thinking correct the inpt shaft group turns the cluster group (where drum attaches to that shaft) which turns the pinion. Is there some sort of clutch on chain to belt drive that would allow a slippage if front got bound up. Anyway hope it's nothing serious , and that's some artful/fine work you did. You can almost check for bearing failure byassesing how much it moves by hand up/down front/back, do same with input shaft. You may be able to turn by hand and "feel" a bad spot (teeth broken). I'm no expert, you probably know all that already, exchanging ideas sometimes brings it to focus! 953... good idea to relieve stress on cluster/brake shaft! Edited January 7, 2014 by groundhog47 Share this post Link to post Share on other sites
sorekiwi 761 #5 Posted January 7, 2014 From your description Mark, it sounds like a bearing failure to me. I have never seen that particular bearing fail before, but I have only been inside about a dozen of these transmissions. The fact that you have hung a drive sprocket off the end of that shaft may load that bearing a bit more, but I really think that the bearing should be able to handle it. Quite likely that the bearing was marginal to begin with. I think I would just open the case and rebuild it with new bearings. If the problem reoccurs then you have a design problem. I'm guessing that it will be fine. Share this post Link to post Share on other sites
meadowfield 2,595 #6 Posted January 7, 2014 I'm at work till the weekend, but sounds like I might have to split it to take a look. It's a shame as it was on the floor two weeks ago !!! The design of the gear was done such that I could mount an external bearing onto the drum and fasten to the transmission. Share this post Link to post Share on other sites
Don1977 604 #7 Posted January 7, 2014 That's not a very heavy bearing at the brake shaft. I changed the seal on my 1977 8 speed last year and its still leaking some so I am due for some new bearings. I changed those the late 80's after breaking a bearing on the other side of the transmission. I believe it was an the same shaft. That extra load on old bearings could be your problem. Share this post Link to post Share on other sites
Stigian 1,234 #8 Posted January 8, 2014 I guess the way to look at it is that the trans still works, so any damage can't be too serious.. Good luck with it Mark, hope it's an easy fix. Share this post Link to post Share on other sites
meadowfield 2,595 #9 Posted January 8, 2014 Thanks for the comments so far guys. Fingers crossed for this weekend Share this post Link to post Share on other sites
Anglo Traction 761 #10 Posted January 8, 2014 As Don mentioned, The seal is likely to leak if the bearing is worn/damaged resulting in slop in the shaft alignment. That in turn will reduce Gear Tooth engagement and can produce noises. Have you got any oil seeping out around the Brake Shaft Seal Mark ?. Either way , I hope it's not serious and is repairable. Oh, no luck on the Front Axle Diff Lube. Has it got a Fill Plug/Level line and a drain point?. Or are there grease points?. Forgot to check/look at the IPL. Can get one of those if you still need it. Share this post Link to post Share on other sites
meadowfield 2,595 #11 Posted January 8, 2014 (edited) it does leak a little, but nothing major. It has however dropped a lot of oil from the RHS axle seal over xmas which is a little annoying. This is the only horse that has never leaked despite reusing the gasket between the two halves. All the others leak, despite new gaskets and blue goo (hylomar).... I did take another look at what I had last night on the web - 99% certain it's typical 80's peerless and uses a liberal amount of bentonite. There are only two ball races in the box and one thrust race. Early peerless used oil - which I'd be far more comfortable with. Fingers crossed the bronze bushes, etc are up to the job. Maybe I will end up stripping it just to check :/ Edited January 8, 2014 by meadowfield Share this post Link to post Share on other sites
meadowfield 2,595 #12 Posted January 12, 2014 Ha, Good news.... Because I've dropped the transmission, the clutch spring that normally presses the brake band and arm against the transmission doesn't... The angled piece was clicking on the chain ends like a ratchet Panic over, a small mod with a bracket has sorted it. 2 Share this post Link to post Share on other sites
sorekiwi 761 #13 Posted January 12, 2014 Well that was an easy fix! Share this post Link to post Share on other sites
groundhog47 347 #14 Posted January 12, 2014 Ha, Good news.... Because I've dropped the transmission, the clutch spring that normally presses the brake band and arm against the transmission doesn't... The angled piece was clicking on the chain ends like a ratchet Panic over, a small mod with a bracket has sorted it. Wow, that is good news, thanks for letting all know! Share this post Link to post Share on other sites
