Super Jet Midshaft/Coupler Alignment

What is an acceptable gap for the coupler when installing an engine? I mocked it up today and had about 1/2" of open space all around. I'm running a full 61x in a SN. Should I just put the bolts in and see how far back I can slide the engine or start looking at the midshaft first? How far should it be pressed through the bulkhead?
 
Location
CT
According to the manuel you have to have the gap betwen the couplers between 4-6mm and the other alignment is finding a flat edge and laying it accross the top of the 2 couplers that gap shouldnt be more than .6mm i belive. it is easist to stut off all the lights and drop a lightinto the hull so you can see the light comming through the gap. also make sure that the 2 bolts on the pump that are shimmed are disconnected and make sure you lossen the other 2 a bit, than after the engine is shimmed you reshim the pump...
 
So since the gap is way over any of the limits listed here, should I pull the motor and midshaft and start from scratch with re-shimming the pump? I haven't done this before and don't get how re-shimming everything will close a gap that big.
 

tomski

X
Location
LHC
5 to 7 mm between the couplers

2mm to 4mm is the number.

According to the manuel you have to have the gap betwen the couplers between 4-6mm and the other alignment is finding a flat edge and laying it accross the top of the 2 couplers that gap shouldnt be more than .6mm i belive. it is easist to stut off all the lights and drop a lightinto the hull so you can see the light comming through the gap. also make sure that the 2 bolts on the pump that are shimmed are disconnected and make sure you lossen the other 2 a bit, than after the engine is shimmed you reshim the pump...

Is Manuel your mechanic? Or do you mean Service Manual?
 

Sanoman

AbouttoKrash
Location
NE Tenn
Ya know,it looks like the measurements vary from one person to the next. Apparently all these numbers will work,

How about not to close and and not to far away............
 

Bobert540

Site Supporter
Location
Rockford,MI
So since the gap is way over any of the limits listed here, should I pull the motor and midshaft and start from scratch with re-shimming the pump? I haven't done this before and don't get how re-shimming everything will close a gap that big.

How far is your midshaft sticking out the back??
 
Not sure. I bought the ski last year and never noticed an issue until yesterday. This is the first time I've had the motor out and I don't remember seeing a gap when I pulled it initially (that was last September though so I may have had the issue then). I'm going to try again tonight to get it lined up properly. If I can't I'm going to pull the midshaft/housing and measure to see how far it is pressed through based on the specs in Jetmaniac's thread from burton148.

Would the shaft itself being pressed into the housing too far be the only way I could have such a large gap between couplers? How much wiggle room is there in the spline overlap?
 
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