Bad to use prop puller on Duo Prop?

[R Steele]

Hi all, first post.

Was hoping to get opinions re: use of prop puller (e.g. Proptopuss) on a duo prop setup. Have been advised by one mechanic to never use a prop puller on this system due to potential damage to internals of the lower unit + the long length of the inner shaft (long length risks bending shaft I guess). He wants to use torch to heat the props (aluminum) to melt the rubber enough to remove props from inner hubs.

Thoughts?

I'm not getting anywhere with trying to use penetrating oil, wood blocks and sledge, etc. The spline grooves are just too restricted to get the oil down in there.

Thanks!

 

[Maclin]

Re: Bad to use prop puller on Duo Prop?

I would let the mechanic handle this one. Once any prop is corroded-welded to the splines the best thing is to trash the props in my opinion. The inner DuoProp shaft is a lot longer than single prop, so the advice goes double for that setup

 

[mpsyamaha]

Re: Bad to use prop puller on Duo Prop?

I have used a puller on duoprops many times. Never had any damage to anything other than the props themselves. What often happens is that you pull the prop off of its hub and then are left with just the hub to deal with, and an air hammer or air chisel will get it off pretty quick. Melting the hub with a torch is an option, but you will likely burn up the prop shaft seals, which you would rather not get into. Either way you are getting the props rehubbed.

 

[R Steele]

Re: Bad to use prop puller on Duo Prop?

Thanks for the tips.

I'm now finding a lot of other issues with this boat (a hand-me-down), so where to best apply $ is a concern. I'm hoping not to have pay upwards of $200 for the prop removal, especially given the impression that the old props won't be salvageable and will need 2 new ones. I know the front one is missing about an inch off the top of one blade and I've gotten the impression that the labor cost to rebuild it will be steep, not including a new hub.

I do share the heat damage concerns regarding seals, etc.

If I decide the props are trash, is it worth considering just cutting the outer portion away with an angle grinder (since I don't actually have a puller at the moment) and then attacking the residual hub (which I assume is rubber followed by aluminum against the steel prop shaft) in the manner described by mpsyamaha?

PS, I've just discovered the V8 engine is seized (hasn't been cranked in 18 months). Joy Joy

 

[billbayliner]

Re: Bad to use prop puller on Duo Prop?

I am guessing you have an AQ series solid hub?

I have had to cut these off before because they were seized on. THIS IS not a job I would trust to anyone as the prop shafts can easily be damaged and you cannot believe the mess with the rubber all over the place.

One drive I purchased had pristine props and I refused to cut them off. I was adamant I would find a way and save them.

Here is what I came up with. I am still using these props today.





If the images do not come up here is a direct link to a picture.
http://i223.photobucket.com/albums/dd114/1login/DSC01941.jpg

 

[R Steele]

Re: Bad to use prop puller on Duo Prop?

Thanks! I do have the tools to attempt that. I did not know what "AQ series" props were, but yes, mine look exactly like that. The pics make everything look a little larger than the real thing.

So after tapping the holes, were you still able to use the props without rehubbing?

My shaft has a threaded hole for a bolt. Any suggestions re: engaging the puller tip against it?

Is light heat against the end of the shaft something to consider?

 

[billbayliner]

Re: Bad to use prop puller on Duo Prop?

Heat is to expand. You will expand the shaft into the prop. I do not think the seals would like the heat either. I never re-hubbed and used the prop as it looks. Lots of meat in those hubs. You will find out if you have to cut them off.

Just place something over the taping for the prop cone bolt so not to damage it. Can be a washer etc.

You do notice how perfectly centered the drilled and tapped holes are???????

 

[R Steele]

Re: Bad to use prop puller on Duo Prop?

I hadn't noticed your 'perfection' till you mentioned it. Awful close to the shaft on the rightmost hole. I'm sure my attempt won't be as good as yours however. How deep are the holes?

 

[R Steele]

Re: Bad to use prop puller on Duo Prop?

Bill, your solution worked like a champ!

Additional info to help others...

I had the stern drive off for other reasons. Made a simple wooden stand modeled after some found on this forum that allowed me to lay the unit over 90 degrees and get the prop shaft vertical. Drilled and tapped 5/16" holes about 5/8" deep. Used 5" full threaded 5/16" bolts, each with 2 washers and a nut for pulling. Also used a 1" long bolt with washer in the hole on the end of the shaft to act as a cap to protect it. Can't remember the diameter of this bolt but it fit inside a 12mm nut without the threads engaging. Would've used a very short 12mm bolt (size of stock prop bolt) but Ace didn't have any in stock.

Put a few turns on it till it got real stiff but the prop still wasn't moving. Kept the tension and poured a 50/50 mix of ATF and acetone into the 'cup' around the shaft and left it for a day. After that it finally began to budge. Had to re-adjust the puller setup once due to the length, so seated the stock prop bolt into its hole and pulled against that. Came free soon after.

Luckily, the forward prop pulled off by hand!

Thanks again for your great suggestion!