Gimbal ring shim source

[oldgmfart]

So I'm sorta new still and going back together with a 1974 MC-1 888/302 transom assembly (without gimbal trim sender), and am setting up the gimbal ring height. Merc Manual #2 states on page 6A-30 "add or remove shim washers under steering lever to correct clearance" (clearance must be between .005 and .030). I checked clearance before teardown and was right at .025 thousands total, just under the max spec. Currently there are 2 shim washers in there, one measures .018 and the second measures .062. for a total of .080 in. in shim thickness. (I'm likely +/-.002 due to cheap digital calipers)

I'm looking to get back down toward the minimum spec. of .005 thou. clearance, so I'm gonna say I need to add approx. .020 in shim in order to get back to .005 gimbal height clearance.

Question is...who has "selective" shim washers available for these old dolls? All I seem to find for parts availability is Upper swivel shaft washer #12-32996 (.015) and washer #12-32997 (.063). Is that it for shims out there?


Correct me quickly but I believe I want to change out the .018 thousands shim for a .040? shim to arrive at the minimum clearance called for? Or, can I just pop in a third .015 thou shim from mercruiser and achieve the same thing + or - a couple of thou? Would there be any issues going with 3 shims instead of 2 under that steering arm? ...or do i seek out a source for a stainless steel .040 shim that fits the swivel pin? How do the big boys cure this one?


Ted

 

[achris]

Re: Gimbal ring shim source

Hi Ted,

No problem with using 3 shims, and they are still available from a Merc dealer or online. I use http://www.mercruiserparts.com/ they are $2.72 there. I'm sure that won't break the bank. The only available sizes are 15 and 63 thou, so one of the 15 thou should do nicely (will give you 10 thou not 5).

HTH,

Chris...........

 

[stonyloam]

Re: Gimbal ring shim source

Well I don't have anything better to do so.... You have .080" in shims and 0.025" clearance for a total of 0.105. You want to get to 0.100" in shims for 0.005" clearance right? Assuming the clearance was originally 0.005" you have about 0.020" ware in 37 years, or lets call it 0.0005" per year, so if you add the 0.015" shim that will take you up to 0.95 total. At the current rate of ware that would give you 30 years to get back to where you currently are at 0.025" clearance, still in spec. Seems like adding a 0.015" shim should be fine. Remember you estimate of error is +-0.002, so if you try to go to 0.100 shims you could be at 0.098" or 0.102 too tight. Remember things might change a bit when you bolt everything together again. Personally I would say "in spec" and put it back together, but that is the old farmer in me

 

[oldgmfart]

Re: Gimbal ring shim source

Excellent! I didn't consider the ware-per-year angle Terry. "In spec" is all good and fine, but I've read that excessive play in this area is a potential source for vibration and noise. ...and since I'm in there with all new bearings, seals and bushing, I'm wanting to get it back down around minimum spec. BTW, your reply just cracks me completely up, and goes to show that good ol' farm boy technology is alive and well! Thank you much.

And Chris, that most definitely helps me. Looks like adding a 3rd .015 thou shim it shall be.