Would this be possible ?

[labzman3]

I am still trying to get a "round " style coupler to go into my crank/flywheel. Since my 1985 motor was shown taking either/or style coupler, and after seeing a recent post of someone here swapping a newer motor that was blown to an older one. He also went from a round style to a triangular one.

So correct me if I am wrong fella's ,,, my flywheel is 12 3/4 inches,, and has tapped holes along the outside edge, so I should be able to use the triangular style coupler right ?

I have a new round style sitting here, but the protrusion on the back is much larger than the hole in the crank ?

1985 Merc. 120 hp.
# A492171

Let me know if I am wrong ??
THANKS !!!

 

[Bondo]

Re: Would this be possible ?

Ayuh,... I Think you need the 14" flywheel for the triangular coupler...
And,.. I know the flywheel cover has a much larger hole in it for the triangular coupler...

 

[labzman3]

Re: Would this be possible ?

Well,, I give up then Bondo !!! I guess thats what I get for having a Chevy motor in my boat !!!

Pretty bad when Mercury can't even tell me what coupler is SUPPOSE to go onto the back of my motor !!

I know this round one I have here is not going to go onto the crankshaft,, without some machine work being done !! And It looks like you are correct about the triangular style,, the bolts holes,, on the flywheel,,, from what I have read,,, are not spaced right for it !!!

Well I think I am close to my second happiest day of being a boat owner !!!!


Later !!!!!!

 

[Bondo]

Re: Would this be possible ?

Ayuh,... Have you got any Pictures,... I donno what you've got goin' on...

There's Only 2 different versions of the little round couplers,...for Chevys anyways...
There's the original, with the 3, 1/2" bolt pattern, 'n 1 with the 3" pattern for mounting newer motors to older drives...

Is there Any chance you have 1 for the Ford/ 470 motors,..??
I donno the measurements of those, as I haven't messed with 'em...

Just a thought,... Any chance you've got a bushing in the crankshaft pocket,..??

How does your New coupler compare to the 1 you removed,..?? other than the .035" difference I mean...

 

[wire2]

Re: Would this be possible ?

....
So correct me if I am wrong fella's ,,, my flywheel is 12 3/4 inches,, and has tapped holes along the outside edge, so I should be able to use the triangular style coupler right ?

....

When I converted my '84 OMC stringer to Merc Alpha gen 2, I ran into that mismatch problem. I took the flywheel and triangular coupler to a machine shop, they laid out & drilled new holes in the coupler, I cut the excess tabs off. It fit perfectly.

 

[labzman3]

Re: Would this be possible ?

Bondo,,, All I know is it's the ole" chevy 2.5 liter motor,, and I know by talking to Mercury that they changed couplers in mid production,, I was hoping that maybe it would take the triangular style,, but after reading your comment and doing other reading,, looks like thats a "no go " !!!

I guess I will just take coupler and have it machined down,, besides,,, the coupler is actually held on by the six bolts,, but I see the protrusion as sort of a centering device ??

I spoke with a family member the other night,, who is a car mechanic,, he said he has done 2 round style couplers on peoples boats,, and they basically tapped on into place !! This is just how things go for me !!!!!!!!!!!!!!!!

Thanks for the help fella's & listening to me B-tch !!!!!

 

[labzman3]

Re: Would this be possible ?

Bondo,,, just finished reinstalling flywheel studs,,, mine measures 3 1/2 inches...

The old one,,,,, I have already been chewed out numerous times by my best friend who is a machinist,,, I tossed it in the trash !!!!!! I KNOW ,,,, I screwed up there !!!

I ordered coupler # 710-76850A-2 ,,,,, I am on my second one,,

My motor is a 1985 120 hp. 4 cyl. Merc.
Serial # A492171

Let me know if you guys see anything wrong !!!!!!!!!!!!!!

Thanks,,,,,,

 

[Bondo]

Re: Would this be possible ?

Bondo,,, just finished reinstalling flywheel studs,,, mine measures 3 1/2 inches...

Ayuh,... What's the diameter of the new coupler pattern,..?? The Same,..??
If so, turn it down to match the center hole...

3, 1/2" pattern is what I expected...
The newer cranks are 3"...
I guess you've got some kinda Oddball set up...

 

[labzman3]

Re: Would this be possible ?

Bondo,,, yea that seems to be my luck !!! The bolt holes on the coupler line up fine,, it's just the protrusion on the back is bigger than the hole in the crankshaft !!
Is it normal for a marine mechanic to have to send things out to get machined ? I would have never thought it would be such a pain,,, I even thought by buying Merc. replacement parts,,I would alleviate any problems!!!
I have put clutches in my trucks,, in only a few hours !!! Maybe the next boat will have a Nissan outboard on the back !!! ???????

Thanks,,, Later !!!!!

 

[Bondo]

Re: Would this be possible ?

Is it normal for a marine mechanic to have to send things out to get machined ?

Nope,.. Not at all...

I'd be tempted to grind it off flush, 'n run it on the Studs alone....

Are ya sure there ain't a piece of old pilot bushin' in the crank or something,..??

 

[labzman3]

Re: Would this be possible ?

Yes Bondo,, thats what I thought,,The shops know how much time it takes to make a repair & something like this would just add time !!

I thought about cutting it off or filing it down till it fit,,, I have one more person with an engine lathe to check with,,, and if they cannot turn it down,, then out comes the grinder !!!



When does this become fun ????