Swapping out ujoint splines?

[Dawn Tolliver]

Is it possible to change splines to a smaller diameter one. Due to wrong size circumference of the gimbal bearing being wrong. Stern stays off about an inch from seating. There's 2 rubber rings at base of spline. Should there be two or just one at the very base of the spline. Could that keep it from going in? The other spline slids right in up to where it's supposed to go. Mind you it's just the spline. So can I change them out? I don't want to tear it all apart again! So I thought this might be easier! This is on the boat I couldn't even get the alignment right. Got that figured out. Also other spline feels tight in the gimbal and is the same length as the old one on the drive.Mercruiser sent the wrong gimbal! Should be a warning to test gimbal on the spline before seating for fit! Always think of that **** a day late and a dollar short! Thanks Guys and Gals for any help

 

[Bondo]

Ayuh,...... What drive ya workin' on,..??
The input shafts on all the Alpha 1s, 'n the Gen.IIs are the same,.....
Ditto the gimbel bearings,.....
Are the o-rings greased,..??

 

[Dawn Tolliver]

4184822 mercruiser off a 1971 silvercraft 3.0 4 cyc We put a light oil on the two o rings on the spline. Mine won't go in. But one off of a stern like mine will? Don't get it if you say there the same. Could the o rings be to thick? Mercruiser said they were OK looking at it from the stern laying in my car?

 

[Eric 3.7LX Alpha 1]

If you greased the O'rings that will prevent it from going in. You want to grease the splines only, dry the grease off the O-rings and apply only a bit of oil to them only.

I believe there is only one gimbal bearing size available. What was the part number they gave you?

 

[Dawn Tolliver]

Why are the o rings on the spline for. There's two slots for them. Close to the base about a inch apart?

 

[Eric 3.7LX Alpha 1]

The O'rings seal the shaft to the inside of the gimbal bearing, stopping possible water from entering the boat that way..... should you get water in the U joint bellows.

 

[Dawn Tolliver]

If you greased the O'rings that will prevent it from going in. You want to grease the splines only, dry the grease off the O-rings and apply only a bit of oil to them only.

I believe there is only one gimbal bearing size available. What was the part number they gave you?

I'd have to look it up because he threw package away. It was ordered for the 4184822 info above. That's all I can tell you. Package said mercruiser on it. But could it be wrong? I mean like an off brand part maybe that don't fit. Does anyone know the inside diameter of one for that stern?

 

[Dawn Tolliver]

Just for fun he says he's pulling off those o rings and seeing if it will mount. If so he's going to a thinner o ring. That's what he came up with. I'll let you know how it goes!

 

[Bt Doctur]

Is this the same drive that came off and was any work done to it?
Did you check the alignment with an alignment bar?
Is the length of the inputshaft the same?

 

[Bondo]

4184822 mercruiser off a 1971 silvercraft 3.0 4 cyc We put a light oil on the two o rings on the spline. Mine won't go in. But one off of a stern like mine will? Don't get it if you say there the same. Could the o rings be to thick? Mercruiser said they were OK looking at it from the stern laying in my car?

The other spline slids right in up to where it's supposed to go. Mind you it's just the spline. So can I change them out?

Ayuh,..... What Other splines,..??

Yer original drive is, I'm guessin', a MC-1, 'n bein' yer motor is a GM in-line motor, the original input shaft is 'bout an inch shorter than the input shafts used in All the other MC-1s, Alpha 1s, 'n the Gen.II drives, 'n motors,....

The o-rings need to be there, but should be greased or oiled just enough so's they're "Slippery",.....
They lock the shaft, to the bearin's inner race,.....

 

[Bt Doctur]

your serial number come back as

Find MerCruiser 120 GM 153 I / L4 1972-1978 Engine & Stern Drive by Serial Number Range​

ans shows the inputshaft as 39385A1

 

[Dawn Tolliver]

Well after 3 months at a boat yard. Still don't have the drive on. They to took a spline only to see if it slid in right. It did, alignment right on. Drive still stops about an inch from seating. Anybody else got any ideas before the sledge comes out? Thanks Dawn a bummed out trout fisher wowmen!

 

[Bt Doctur]

what is the length of the inputshaft? You should take the shortshaft . about 8 inches , not the long one 9 inches