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Author Topic: H75 cam for turning "correct" direction  (Read 146 times)

MadeForThat

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H75 cam for turning "correct" direction
« on: January 14, 2023, 04:01:55 pm »
Hi, I imagine this is quite a dumb prompt, and one that I am certain could be avoided by more carefully evaluating the h75 I have torn down next to me, but I am noticing that the camshaft could likely be flipped to run the "correct" direction. only think I am seeing that gets in the way of this is that one end of the camshaft end rod is longer on the governor side than the gear side. If flipped there would be a bit of extra length on the gear side, that would not be an issue with a hole in the gear cover, but having less length on the governor side would mean that the governor may not have enough length to function. Without pulling dimensions it looks to be about 3/16" difference in the end rod lengths, and some flats ground into the governor side that I am certain don't need to be there.  I don't think it is personally worth the effort to try to make it work, but was curious if anyone else had thought down this path already and identified more issues. Considering how upset people are about the water pump direction it seems like someone could potentially offer the service to correct the direction. Allen key for comparative length. [ Guests cannot view attachments ] [ Guests cannot view attachments ] [ Guests cannot view attachments ]

Fullraceflathead

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Re: H75 cam for turning "correct" direction
« Reply #1 on: January 15, 2023, 01:26:47 am »
I was the 1 that 1st mentioned it the engines running in the wrong direction I did notice that they do sell replacement camshaft I think for $36 I do plan on purchasing 1 or 2 and seeing what I can do experimentation wise at some point in the future. While you have apart it would be a good time to install some 1/32 inch spacers made from teflon sheet to prevent the piston pins from scoring the cylinders. Can you tell me the diameter of the piston pin? I have not disassembled mine yet. I want make punch for the teflon discs. I have the teflon material.

rodnoc

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Re: H75 cam for turning "correct" direction
« Reply #2 on: January 15, 2023, 04:16:37 am »
.... spacers made from teflon sheet.....

Another option:

Obtain an o-ring of the correct thickness and slice off pieces to make wrist-pin spacers.

I cut the spacers by hand.  Precision hasn't been necessary, the plugs can't go anywhere.

RobA

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Re: H75 cam for turning "correct" direction
« Reply #3 on: January 16, 2023, 10:38:38 am »
I have mentioned this awhile ago about the necessity to prevent the piston pins scraping against the cylinder walls. I even found this problem in a couple of full size H&M engines that I have.

I punch out some disks from heat resistant trays the frozen food dinners come in. Using a hand punch, either sheet metal or leather, makes it easy. There usually is enough room to place them on the ends of the piston pins.