Volvo Penta 270 drive questions

[HarryReid]

I pulled the 270 drive off my 1984 Bayliner Capri 1950, Volvo Penta AQ125A engine; the goal was to replace the u-joint bellows, exhuast bellows, water pipe and control cable. While I had the drive off I also wanted to give it a fresh coat of paint.

There seems to be many issues and I'm not quite sure where to start as this is starting to look like more than I expected to do in a few days. I would appreciate some input as this all new to me and I'm not sure what is a problem and what is not.
- appears to be gear lube in the bottom of the u-joint bellows; from what I've read I'm guess the input shaft seal is leaking and needs to be fixed
- all housing bolts have white powder on them; I'm guessing someone used lock-tite or something - is that supposed to be done? How do I clean off all the white powder from where they screw into?
- the housing mating surfaces look quite tarnished, see the pictures below; I will be replacing ALL o-rings but I wonder if I need to use a gasket between the housings or have them re-surfaced??

 

[Scott Danforth]

white powder is corrosion.

 

[HarryReid]

Thanks for the reply. Why would thw white powder only be around the bolts?

 

[Scott Danforth]

galvanic corrosion from dissimilar metals. stainless and aluminum really do not like each other, especially if you are in salt water.

 

[HarryReid]

That is good to know! How do I clean the bolts and the holes they thread into? Do the mating surfaces of the housings look okay to you?

 

[jerryjerry05]

I bought a re-threader or tap and die thread chaser.
Used to clean all the holes and bolts and nuts.
The surfaces look good, use a scotchbrite to clean the surface.
When you put it back together use a marine grease to coat the bolts, nuts etc.
Anti-sieze when used in salt water becomes perma-sieze.

The oil or residue could be from the front seal where the u-joints go into the unit.
Depending on the shape of the surface you might get away with a new seal??
Maybe need to replace the yoke(pics) if the rust has gotten bad???

 

[HarryReid]

Thanks!

 

[HarryReid]

Thank you Scott and Jerry, the drive is back together but it looks like I now have another problem, similiar to this thread, http://forums.iboats.com/forum/engin...-above-2500rpm

I know this was not a problem before as I tested everything out, but I must have been too rough with the ScotchBrite and messed up the seals on the yoke. I am going to have to try and find all the seals and someone with a press so I can reassamble the water pipe and all gaskets/sealing rings on the intermediate housing.

While I was replacing other things I noticed this, it looks farily fresh and I'm not yet sure what piece this is but it looks fatal to this boating season...

http://hrconsulting.ca/projects/Bayliner/DSC_0474.JPG
http://hrconsulting.ca/projects/Bayliner/DSC_0477.JPG
http://hrconsulting.ca/projects/Bayliner/DSC_0478.JPG

 

[captmello]

That hole in the flywheel cover is not really a problem, however I'm curious how it got there. It looks like there may have been something mounted there that broke off, but I'm not sure.

Overheating when the boat is on plane is a common issue with these outdrives because of the multiple things that can cause it. Usually it is air leaking in on the intake side of the water pump. You said you replaced the waterneck and the gasket below it. That gasket can be tricky to install properly, Oring side down, right?
Before pulling the outdrive apart, I would have another look at the gasket to make sure it is in properly.

 

[HarryReid]

I had not replaced the waterneck, only cleaned the surfaces between the three housings and replaced the two o-rings on the top and three o-rings on the bottom of the intermediate housing.

Took a video of muffs on the drive and when I placed my finger to plug the drain hole on the bottom of the lower housing, water came out between where the o-ring should seal the waterneck between the lower and intermediate housing. I have also stuffed a hose into the waterneck on the bottom of the intermediate housing and saw water spraying from the top of the waterneck, on the opposite side of where the water pipe connects to the yoke...

I do not know if anything was attached to the flywheel housing... could the bearing have failed and punched that hole through the housing? I did not see any rust when I looked through the hole and the whole point of pulling the drive was to replace the bellows as part of preventative maintenance. The boat hasn't seen water yet this year as it's just one thing after another!

 

[captmello]

I hear ya harry, The old boats take a lot of time and work. while the pivot tube bushing at the top of the pivot tube could be worn down, that gasket under the water neck fitting would still be my first move. Its MUCH easier to do with the upper gear box off however... None of this is going to fix your original problem of the outdrive oil leaking into the bellows...That, IMO, is not a DIY job and will most likely cost 500-700 to rebuild. Its not uncommon. previous owners don't replace the ujoint bellows until they see a crack, by that time the damage is done.

I thought briefly that something may have hit the flywheel cover from inside, but its hard to say. I guess you could pull the motor and see. I found you almost need to do a full restoration on these old outdrives to get them to work consistently. Otherwise your working on it all the time. Is the boat in good shape or is it a beater?

 

[HarryReid]

Thank you, captmello.

The boat has been great until I decided to do some preventative maintenance and replace the bellows! lol

I am not a mechanic so most of this stuff is hugely time consuming to understand and ensure it gets done properly, it wouldn't be possible without this forum and such great people helping!

The stuff in the bellows looks like grease and was around the input shaft, otherwise the bellows looks good; also the seal around the input shaft is in place although there was a lot of grease around it. I did not see any drive oil leaking into the bellows so I am going to focus on disassembling the waterpipe in the intermediate housing and see what needs replacing. I have read here that a spark-plug socket and 3lb hammer will drive it out - I do not have a press and although I'd like to buy one the admiral wouldn't be very approving

 

[captmello]

Oh, grease in the bellows, thats ok.

What you are calling the input shaft is the PDS (primary drive shaft), and yes there is a grease seal that is around the PDS, that the ujoint yoke fits into. there should be no play in the PDS, btw. If so the bearings for that are shot and need to be replaced.

Yes a spark plug socket seems to fit the top of the pivot tube, but dont hit it too hard, a rubber mallot is what I would start with. you dont want to damage the tube which is soft. but when I did mine, it didn't take to much to get it out. Aside from having to remove the entire outdrive and disassemble it, the pivot tube bushing job is not that bad.

Assuming you have the outdrive back on the boat, if you lift the outdrive up and down by hand, you can see how much play is in that spot of the outdrive. If you have a lot of play, then, yes the bushing is most likely shot. If there is very little play, it may just be the water tube gasket.