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alpha 1 gen 1 reseal

sharkin95

Regular Contributor
Found oil in my drivehaft bellows. how difficult is it to reseal the upper driveshaft on a mercruiser alpha 1 gen1 o/d.. not the waterpocket just the yoke shaft seals
 
First you need the special wrench to remove the large nut........then you need the determine what bearing arrangement you have, (with spacer or not between the bearings).
With spacer is just re-torque when reassembled and your done, No spacer requires a rolling torque of less than 6-8 inch lbs and locktite on the threads of the nut that you are torquing.......

The seal is about $30.00 +/-........

it gets pressed out of a aluminum carrier and the new one gets pressed in, pay attention to the way the seal lips are facing!!

Also if the yoke is worn (grove from seal lip) you may need to press the seal back into the carrier a bit further to have the seal lips make contact with new metal surface on the yoke. (a little trick to avoid replacing the yoke assembly) Just make sure you do this in the correct direction and only about 1/32 to 1/16" !!
the direction to over/under press the new seal into the carrier should be understood before doing it.
I would have to be looking at one to tell you specifically and I am not near one right now.

If you don't have a manual don't try it...........
 
I see you live at the cape, I live about 1 hour or so from there. I will gladly do this for you if you want to make the ride.

Bring the whole outdrive and we can pressure check it and do anything else to it internally you may need.

I have plenty of time and all the tools so its your call.

If so message me with your number and I will call you.

Otherwise read below

Make sure you replace the large oring on that assembly and the skinny one under the top lid.
Coat all the orings liberally with PERFECT SEAL and the threads of the large nut that requires the special wrench.

That special nut requires 123 ftlbs torque with a standard 19 inch long torque wrench. So make sure you measure yours to confirm or go by the chart if your is different. Another reason to have the special tool for the nut!!!!

The manual can be a bit confusing so read it carefully. Anything around 120 ftlbs is acceptable

When you get the ujoint/bearing assembly out, there are a few shims and one that looks like a piston ring.

Pay special attention to the order in which they come out or that you take them out.

Prior to reassembly clean the housing the bearings fit into and then coat it lightly with gear lube.

The double bearing assembly MUST be in line to each other (the manual show using a large hose clamp to accomplish this when torqueing them.
it is a very tight fit and if the bearings are miss aligned the assembly will not go back in all the way and may become stuck.

This happens a lot even to me so be very careful
 
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update.... I had an air test on it for 2 days at 16lbs. it droped 1 lb. so I'm a little baffeled, there definetly was oil in the bellows not much tho and oil on the cavitation plate maybe a tablespoon.
 
Try pulling a vacuum on it.
Also did you spin all the shafts and assemblies while under pressure?
 
spun the shafts forward and reverse ....the only vac pump I have is a a/c vac pump I'm a hvac tech by trade. How many hg's do I need to pull ?
 
well decided to change the seals (I'm waiting for the retainer wrench on e-bay) how do tell if you have the rolling method or the 80 lb and done method
 
When you separate the bearing pack there will be a spacer see pic Item 6.

If that spacer is missing then rolling torque

if the spacer is present standard torque

In the time to wait for the wrench you could have driven to me and I would have done the job for you......I have all the tools needed.......

option is still open..........
 
It has the spacer so it's 80lbs torque lube the shxt out of it and slide it in. 120 lbs torq on the retainer.thanks kghost but your at least 1 1/2 hrs away from me, my boat is winterized and covered so I'm in no hurry thanks for the help......
 
well just finished the reseal so far all is good holding @12 psi . thanks to kghost and steverobo that piston compressor worked awesome I got a loaner from auto zone so cost me zero. well here's the skinny of it .....originally went to a marine shop and quoted me $170.00 thats $100.00 labor plus parts. cost me to do it myself $20.00 for the seal kit ( sierra) $18.00 for the retainer nut and 18.00 for the retainer wrench... and zero for God watching over me so I don't srew up.I would rate this a 3 out of 5 for difficulty
 
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