How to remove the prop shaft strut?

[Marjenks]

Hi there,

I have a 20V with a bent prop, rudder and prop shaft strut. I got the rudder off, a new prop is on the way and the strut just won't budge at all!!

I haven't managed to get a single screw off it, I can't even seem to get the right screwdriver size (looks like a PZ5 to me - bigger than a pz4, but none for sale at the best local tool shops). I do have ph4 and pz4 screwdrivers, but they're bending and also starting to destroy the screws themselves so I've had to give up for the moment.

I was wondering if I'm approacing the problem wrong. I'm working from under the boat, but can the screws be loosened from inside the boat instead? It seems impossble as the engine fills the space!

So any tips would be very welcome - correct screwdriver size, correct technique, do the screws turn normally or are they reversed for example?

Thanks

[boatwakes]

Marjenks, you must attack from inside the boat, the screw threads inside have nuts on them that must be removed first before unscrewing from the bottom. Also, the strut and its bolts have been sealed in place by 3M 5200: if you don't hear the low brass section in your head when you read that, just imagine very bad things. However, to get around the 5200 problem, there is a product called De-Bond 2010 that will disintegrate its holding power. It is imperative you do this before trying to remove the strut from the hull otherwise the 5200 will pull the gelcoat away from the fiberglass when you try to remove it. Keep at it and good luck.

[Marjenks]

Thanks a lot boatwakes!

I searched around with a light from the port side of the engine and saw a glimmer of a bolt and realised I needed to move thw two cooling hoses out of the way (for future readers I have a Mercruiser 5.7 V8 engine) to enable me to get my hands and tools into the right area.

I am halfway through, got the first bolt off but a downpour of rain hit so I'm huddled inside waiting it out & ready to pounce on the boat again.

Many thanks & it should be a smooth ride from here.....

[Timmy!]

Good luck! Post some pics for future readers!

[Marjenks]

I tell you what for future readers! I nearly ended up in the hospital after this today, "missed me by that much II" as Maxwell Smart would say.

I had the strut all loose, but although I'd ordered a new prop I hadn't got the old one off yet. Using a heavy duty prop puller I had it as tight as it could possibly be, but the prop wasn' budging. I had a friend helping me to get this done. I gave the prop a few bashes from a heavy duty hammer and tightened the prop puller some more, bashed it, tightened it, bashed it etc. Then when it finally gave, the 5kg prop (badly damaged with sharp edges) flew past my head like a bullet by half an inch, past my friends leg by about the same amount and landed about 5 feet from where it started!! My friend screamed for his life & it happened so fast next to my face that I didn't have a chance to get scared.

So be warned, stand back if your prop doesn't shift easily!!

[dingleberry]

I tell you what for future readers! I nearly ended up in the hospital after this today, "missed me by that much II" as Maxwell Smart would say.

I had the strut all loose, but although I'd ordered a new prop I hadn't got the old one off yet. Using a heavy duty prop puller I had it as tight as it could possibly be, but the prop wasn' budging. I had a friend helping me to get this done. I gave the prop a few bashes from a heavy duty hammer and tightened the prop puller some more, bashed it, tightened it, bashed it etc. Then when it finally gave, the 5kg prop (badly damaged with sharp edges) flew past my head like a bullet by half an inch, past my friends leg by about the same amount and landed about 5 feet from where it started!! My friend screamed for his life & it happened so fast next to my face that I didn't have a chance to get scared.

So be warned, stand back if your prop doesn't shift easily!!

That's exactly why you should leave the prop nut on the shaft, just loosened but still on the threads.

Glad that you weren't injured.

[JustWantToSurf]

I understand

That's exactly why you should leave the prop nut on the shaft, just loosened but still on the threads.

Glad that you weren't injured.

So....I have been banging away on my propeller and it is not moving yet. I feared the same flying propeller scenario. I hear heating the shaft of the propeller is the next step...or should I just bang harder and duck. BTW on my boat and or with my c clamp you cant keep the bolt on and the c clamp ant the same time.

Thks...

[dingleberry]

So....I have been banging away on my propeller and it is not moving yet. I feared the same flying propeller scenario. I hear heating the shaft of the propeller is the next step...or should I just bang harder and duck. BTW on my boat and or with my c clamp you cant keep the bolt on and the c clamp ant the same time.

Thks...

This thread discusses several suggestions for a stuck prop, and the less extreme but successful solution in this case was to keep moving the prop puller around in different positions: http://www.tigeowners.com/forum/showthread.php?t=15239

Not sure what to suggest if you cannot fit the puller on with the nut still in place. Just please be careful. Good luck!

[Marjenks]

Outstanding advice to leave the bolt on the shaft!! My helper is a licensed Norwiegan fishing trawler captain so I'm amazed he didn't tell me that on the job!!

Re the discussion of getting hard props off, this one was nasty but we were using a prop puller that was different from the c clamps in that it grabbed from both sides so the force was completely even. I was able to bash it with a mallet simply because it has been so destroyed by the rocks that it didn't matter what further damage I did to the prop after that. I don't envy anyone who wants to both get it off and also leave it undamaged!!

[Donnyparks]

Thanks guys, have same problem with mine, left nut on and put bearing puller on tight, gave a light hit to prop with brass hammer and off she came. Now to tackle the strut. How is it going with your one Marjenks?

[Marjenks]

I got it all off after the prop, the strut was super tight, I had to use a friend to force the tool up by using a levered timber against the trailer as I wasn't able to hold the tool up tight enough to the screws. Once the screws were loose the strut just came away despite warnings about glue.

My friend works at a local machine parts factory where they make robot parts, so he asked a colleague if he could straigten the rudder and strut. The rudder was done but he couldn't straighten the strut so he made a whole new one which just blew me away! It was actually better than the original with a grease injection point installed so I can keep it greased easily. I popped it all back on and have been back on the water quite a few times now.

Thanks for the comments and answers that helped me get it done, I must have saved a small fortune not handing it over to a marine mechanic!