Rake Timing

[riversidesmechanic]

I have a rake cam that keeps slipping. Every two or three cycles it is off and the rake will not raise. The Rake latch assembly locks before the cycle starts causing the rake to sweep 10" off the deck and catches the hanging pins. What would cause this to happen? I have adjusted the timing several times, so no loose hardware or anything. Is there a keyway on the shaft maybe broke?

[Roscoe]

Riverside:
The clamping plate can be put on backwards IE: wrong side out. It has a rounded outside periphial and a sharp outside periphial. Put the sharp corner to the cam, sometimes a small shim is required if placing the sharp side in, fails to correct your problem.

[riversidesmechanic]

No one has taken it apart that I know of it just started the other day after I replaced the rake latch assembly and made a full rake adjustment, including timing via Steve Stafford's rake adjustment. Then ran the machine after timed the rake and the trip bracket on the rake latch locked before it was suppose too. I dont think the cam is slipping but the time keeps getting off somehow.

[Steve Stafford (JBEES)]

Keeps locking before its supposed to? It should happen somewhere near 45 degrees. How soon is it locking?

[Roscoe]

Make sure the main rod bushing is not loose in the head casing of the latch assembly. That will cause the problem your experiencing.

[keeth]

Any chance of your rake cam follower bearing being frozen? This can cause the cam to be pushed retarded at 180 and at raising time after 270.

[riversidesmechanic]

@ Steve When I spun the cam It was nearly 180 degrees from where it was supposed to be. it doesnt start doing this at first. I adjust the cam and I would say after 3 or 4 cycles it starts getting off time. That is when the latch assembly starts to lock right as it sweeps, so I checked the keystock on the shaft, it is good.

[riversidesmechanic]

@ Keeth It is retarding itself slowly, I will adjust the timing and after a few times of unlocking the latch and then cycling it goes back to doing it again.

[riversidesmechanic]

@ Roscoe I completely rebuilt the latch assembly with new parts, it is working fine. The cam is retarding itself slowly counter clockwise.

[Roscoe]

Then check that plate, if its right, make a shim of a circle of solder wire wrapped around rake cam hub.

[Carl D]

New spring washers on the 6 bolts for the rake cam might also help.

[john dubose]

i have had to replace the clamping plate to stop this but never thought of the solder shim method.

[Steve Stafford (JBEES)]

Just a thought...take another clamping plate from another machine and move the one on this machine over to the other machine. Be sure you keep the same relationship as far as outside to inside on both clamping plates. See if the issue follows the clamping plate or if it stays on that machine. I think this would eliminate the clamping plate as the issue or it will point straight to it.

This will take less than ten minutes to do...and should answer some questions. Just be sure you do this at 90 degrees on both machines and be sure the rake lift cams do not move while swapping clamping plates. The pressure from the rake lift cam followers should help insure they do not move.

[riversidesmechanic]

Thanks guys for the great help! The clamp from ln# 3 worked on ln# 4, which was the problem lane cycled many times no problems. Now do I solder the flange clamp or just put a piece behind the clamp to help clamp down the cam.

[Kanga (James)]

The solder wire sounds like an idea. Gotta remember that one.

Keeping the gap down to (at most) 1/32" between the roller and notch on the rake trip shaft will limit some jerking against the rake lift cam during cycling which will contribute to the problem.