Alpha one gen 2 drive shaft scratches

[dlogvine]

I was rebuilding an outdrive yesterday and after removing an impeller found that there was some significant scratching on the drive shaft right under the impeller. In other places the drive shaft is smooth and clean. How damaging could these scratches be to the outdrive gears and overall running? I would really hate to take the whole gear case apart to replace the drive shaft, also it could be quite expensive, since this is a budget project boat for sale. I'll post a couple pictures of the shaft a couple hours later.

 

[dlogvine]

No Title

 

[dlogvine]

Crap, while rebuilding the outdrive i discover two more problems, one of the impeller housing bolts is slipping inside the hole and does not tighten up. Should i drill and tap a bigger hole for a bigger bolt or is there another way to repair it? Second, i had to remove the impeller housing after the gaskets were sealed so i damaged the gasket a little in the corner. As common sense tells me i should get a new gasket set but can i use more of the gasket sealer to seal it up?

 

[wrench 3]

The scoring on the shaft shouldn't bother anything as long as the impeller slides over them OK. Nothing moves there anyway, as long as the drive key is in good shape.
You can repair the thread in the bolt hole with a Helicoil. If you're in good terms with an automotive machine shop they may lend you an installation kit. You drill out the hole, re-tap it and insert a coiled insert to bring it back to the original size. If you can't borrow a kit, kits for a single size thread aren't terribly expensive.
As for the gasket sealer, it looks like you used too much the first time. A good gasket on a smooth surface doesn't need silicon sealer. A brush on gasket sealer can be used but all I use is a bit of grease. If there are irregularities in the surface a small dab of silicon is good but the amount you had on there may get into the impeller. The gaskets can be purchased individually.

 

[dlogvine]

Thx buddy, i found the old top gasket, it is in a good condition, so ill clean the wear plate and put the old gasket on. The bottom gasket is intact, did not use much sealer on it. The screw problem resolved itself, the screw was a little short, the tappered end was not going deep enough, will get a little longer bolt. Good thing i looked again, tried to blow the air through the lube oil pasege and blew out a ton of debries, they would have definitely clog the passage and block the gear lube flow. So looks like it goes slowly but in the right direction.

 

[Bt Doctur]

Good thing i looked again, tried to blow the air through the lube oil pasege and blew out a ton of debries, they would have definitely clog the passage and block the gear lube flow. So looks like it goes

The bolts ARE NOT tapered, they are straight. m6 X 16 get the correct tap and clean the holes first.
A So you applied air pressure to the small hole in the case and blew debris into the lower gear case?
B You applied air to the bottom case drain plug and blew debris out of the oil transfer tube?

 

[Rick Stephens]

The Doc is right, blew debris from where, to where?

Also, no need ever to put sealer on a water pump, there is water on both sides. Accomplishes nothing.

I would use a small piece of emory clothe to smooth the shaft where it is scratched up, just to make it easier to install the impeller. No need for that area to be perfect.

 

[dlogvine]

The chipped paint and old oil was making the most of the gunk inside of the gear lube passage in the lower unit passage. I tried to clean the passage from the top of lower unit with a thin metal strip (i used an insert from the car wiper blades and then a thin screwdriver). I had a feeling that something was blocking the passage. Also when i was draining the gear lube oil it was draining much slower than it was supposed to. I also tried pb blaster to clean the passage and to see how good is the flow. The oil was going through but very slowly.so i blew the compressed air from the top of the lower unit hole into the gear case, but due to strong pressure it all went in the air. Should i also try to blow the hole from the lower unit oil plug? As for the bolts on the impeller housing, im 99%sure they are tappered at the end, can even photo them tomorrow.

 

[achris]

.... Should i also try to blow the hole from the lower unit oil plug?

That's what you should have done first... but you now have all that crap and gunk inside the gear housing. A few options. 1. Disassemble and clean the gear housing out. 2. Try and wash the crap out with a very thin 'flushing' oil. 3. Ignore it and let the poor sucker who buys the boat deal with it when the bearings chew up....

As for the bolts on the impeller housing, im 99%sure they are tappered at the end, can even photo them tomorrow.

And I'm 100% sure they are not. Use an M6 'plug' tap to clean the threads. If you have one stripped, use an M6 helicoil kit and restore it to original. Please, don't try and tap it larger and use a larger screw... That will cause more problems than it will solve. The gaskets, plate and impeller housing holes are designed for an M6 screw. Use a large screw and you'll need to open the holes up, and that will not end well...

Chris.........

 

[dlogvine]

Thx Chris, you are right, the bolts were not tampered, my bad, was working late at night and did not see well. today looked at the outdrive and the impeller housing bolts and realized two things. first the bolts are straight, second and the most important, the bolt was strpiped at the lower third of the thread, that caused the slippage, bought a new bolt at ace hardware and it worked just fine. So, no need for the thread repait. one other thing, I realized that the top, front bolt is missing, so I bought a couple bolts of various lenths to replace it, but looks like they were both too short at least by 1/3 of an inch. can't find the specs on this bolt, if anybody knows? Also removed the torn gasket from the wear plate and replaced it with the original that was there before, it was in a good shape, still flexible, no wear. think it will work.

 

[wrench 3]

If your talking about the bolt holding the lower gear case to the upper, it's a 7/16 course X 1 3/4" assuming that your using a bolt and not a stud and nut.

 

[dlogvine]

Thank you, I was trying to use 3/8 of various lengths. Seemed like it was fitting until the last tightening turn, when it started slipping. I was ready to use thread repair. Will try new bolt tomorrow