Towing your boat behing a houseboat with dripless shaft seal

This has been brought up in a few different forums, wanted to get feedback from WW members. It seems there are a lot of different opinions on this...

If you tow your boat behind a houseboat with a dripless shaft seal will damage occur to the seal from lack of water being introduced into the seal unit. The prop will be spinning, and there might be some water forced into the scupper, but is it enough to cool the shaft and not damage the seal? how fast is th prop actually spinning at houseboat cruising speed?

I do this when I am on Lake Shasta, and wanted to find out if I am taking a chance of the seal being damaged. My last boat had a dripless shaft seal and failed prematurely at 230 hours, I am now wondering if this was the cause of the failure.

Thanks for any feedback...

I have never heard of this being an issue. I doubt your prop will spin too much while being towed. I wouldn't worry about it. Enjoy your trip to Shasta!

I doubt it would spin enough to hurt anything especially at the slow speed that a typical houseboat would move. If you're worried about it couldn't you just put it in gear to prevent it from spinning at all? My dad used to do this when trailering outboards because the props spin pretty good in the wind on the highway and he said it would hurt the seals. An inboard seems to provide a lot more resistance to spinning even when in neutral relative to an outboard though.

I am not sure that 230 hours is premature. These things fail with some regularity. I am sure someone is going to pipe in that their shaft seal has not failed after 42 million hours, but nonetheless, I would wonder if it was just coincidence that yours failed during the houseboat trip at that time.

TTG, I'll be that guy. Three boats, 2000 hrs, never anything more than an adjustment

Including a dozen houseboat trips. So I'd say do it, check it, and react from there.

Originally Posted by Jeff

I doubt it would spin enough to hurt anything especially at the slow speed that a typical houseboat would move. If you're worried about it couldn't you just put it in gear to prevent it from spinning at all? My dad used to do this when trailering outboards because the props spin pretty good in the wind on the highway and he said it would hurt the seals. An inboard seems to provide a lot more resistance to spinning even when in neutral relative to an outboard though.

My boat has drive by wire, so there is no cable to keep the transmission in gear (I am assuming the boat will not remain in gear once shut off, I could be mistaken). I was told these seals should last 400-500 hours before starting to leak. A member on the Malibu Crew site explained how he burnt a seal up on his boat by towing it behind a houseboat on Lake Powell. I have no idea how fast the prop is spinning when towing behind a houseboat, have never checked the driveshaft while the boat is being towed to see if it is spinning.

if your that worried about it you could just remove the prop when in tow.

I remember someone on a forum somewhere chewed up his dripless seal by towing in the water without locking the shaft. I don't believe putting the trans in gear will keep the shaft from spinning. Inboard transmissions are like slushboxes in cars. Beyond that, no water coming thorugh your scupper for raw water intake will make it past your raw water pump. Doesn't matter how fast your towing, none will flow through.

Putting the trans in gear will not stop the shaft from spining. With out the engine running there is no hydraulic pressure to engage the clutches. As far as damage while towing I am sorry I cant answer that question, but if your worried about it I am sure you could come up with some very easy solutin on how to lock the propshaft in place. Have you confirmed that it does spin while towing. I didnt think it would but have not ever check it. I would check it and if it does lock it in place.. good luck let me know if you confrim that it does spin.

Ive heard of guys wrapping a rope around a blade to keep it from spinning. Idk if that could hurt the prop, but if your towing slow enough it should be fine. curious to hear what "should" be done.

how about just drive it, don't tow it. I'm sure you will have more than 1 boat driver so no real need to tow it.

Matt Bird - Not sure if you have ever removed a prop, impossible to do under water, even a PIA to do on the trailer, so this is not an option. Definitely would be a major hassle to pull on the trailer.... this option is just not do-able.

I can definitely drive the boat, not a big deal, just nice being able to tow. Sounds like I am going to have to contact OJ and talk with Eric, nobody really seems to know what will happen in this situation.

Thanks for the feedback....

Travis do you have a temp gun? They are cheap these days and you should have one for trailering anyway.

Drag the ski boat for a while and shoot the shaft seal. If its getting warm lock down the shaft or drive the boat. BTW a strap wrench works great or a rolling hitch if you can tie one.

If its (shaft seal) within a few degrees of lake temp then have a beer and relax. Get one for me while your in the cooler.
John

A temp gun would be great, but I should have a temp gun for towing, really?

Originally Posted by wakedoctor

.., but I should have a temp gun for towing, really?

I'm assuming he's talking about using it to check the temp of hubs and brakes. Not a bad idea. I usually just check carefully with my hand but getting an actual temperature reading would be more scientific.

No, he's talking about using the temp gun to see how hot your seal is getting. Just like with a regular packing you adjust but always verify, with your hand at least, that the seal is not running too hot. Your seal or packing nut shouldn't get more than warm. If it's hot you've got a problem.

It's the same idea as walking around your truck while towing or driving long distances. I always do this and feel the hubs on the truck and trailer, just to be sure nothing is amiss.

Originally Posted by cadunkle

No, he's talking about using the temp gun to see how hot your seal is getting. Just like with a regular packing you adjust but always verify, with your hand at least, that the seal is not running too hot. Your seal or packing nut shouldn't get more than warm. If it's hot you've got a problem.

It's the same idea as walking around your truck while towing or driving long distances. I always do this and feel the hubs on the truck and trailer, just to be sure nothing is amiss.

I am aware of using the temp gun to check the seal. I just found it funny that the advice was given that we should have a temp gun for trailering.

Hmm..... Interesting... I would have never given this the slightest bit of thought. We've towed a ton of boats behind house boats without any problems.

I would have to say just watch it while you're towing. Take off the center rear seat so you can see the prop shaft and see if it's turning. If it is and you're worried about it, then I would probably just take a dock line, tie a loop in one side, wrap it around a prop blade and tie it to a cleat. Maybe keep a bandanna or something in the boat that you could tie around the steering wheel to remind yourself that the prop is tied up.

Let us know what you find.

@ travis,

I have removed a prop before and yes you can do it while the boat is in the water.

Is it easy? No.

But since you seem to be so worried about it I thought it might be a viable solution for you.

Apparently not.

Temp gun for trailering advise was to check hubs and tires. A hot tire will indicate a dragging brake. Hot hub= bearing etc. you get the idea. Salt water trailers give a little more grief and are deserving of being more closely watched on longer hauls. My advise is based solely upon my experience.

Just today on sea trials I had yacht with original series Tides shaft seals. They both looked fine at the dock. Once under load the port read right about sea temp, the stbd was reading almost 109 degrees stared ;leaking before my eyes and was going fail catastrophically any second.

The idea is that the OP can shoot the shaft log without doing Circus tricks and know if it hot or lake temp.




It was just a suggestion, and worth what you paid for it. You sweet water guys do things how you see fit.
As you were....

this was today

Oohhh thats allot of typos even for me..

I guess I need a home help nurse as well to check my bath water. I am to degenerate to tell the difference between warm and that is too fawkin hot with my hand. Which I guess if I get one of these temperature things I can ditch the nurse with herpes and come out cheaper as well.

Originally Posted by wakedoctor

I guess I need a home help nurse as well to check my bath water. I am to degenerate to tell the difference between warm and that is too fawkin hot with my hand. Which I guess if I get one of these temperature things I can ditch the nurse with herpes and come out cheaper as well.

Very helpful post. Thank you for your insight and suggestions.

The OJ dripless packing gets it's water supply from the engine's circulation pump. Without the engine running, supposedly your starving the packing for any fresh water.

Heres a post by a guy who's had first hand experience with it.

He suggests you "lock the prop", which seems like it would be easy to do like Joey suggests... just tie it in place with a piece of rope.

Obviously removing the prop is another option.... definitely possible, but a bit more difficult.

Interesting.... I have never heard of this. Have you tried to reach under your boat and spin your prop when it is stopped. It is not just freely spinning. I would think the 5 mph you are moving on the houseboat would have a hard time spinning the prop. I could be totally wrong, but now I am curious. Would be interesting to do what someone else said and go back there and lift the cushions and see if it is even spinning..... Follow up on this as I am curious now...

I have seen many boats up at Lake Powell with this problem. The easy solution is to install a "Y" in the supply line and either plumb it to small pump or just install a small hose that goes out the back of the boat that attaches to the swim platform bracket. As the boat moves forward it pushes water up the hose and into the "Y". When they are not towing their boat they simply turn a valve and stow the hose in the locker. I know of at least three boats with this setup. If someone really needs more info I will see if I can get pictures of it.

Looks like it is a valid worry. Here is how Yachts handle this problem:

http://www.nauticexpo.com/prod/brunt...12-189648.html

Originally Posted by ldr

@ travis,

I have removed a prop before and yes you can do it while the boat is in the water.

Is it easy? No.

But since you seem to be so worried about it I thought it might be a viable solution for you.

Apparently not.

Matt,

Thanks for the suggestion, I am just not that talented to take a prop off under water... I would be afraid of dropping something and having it end up at the bottom of the lake.

Little update for anyone interested....

Just got off the phone with Eric from OJ props, he said there is no problem with towing your boat behind a houseboat. Not necessary to lock driveshaft or remove the prop. Infact, he mentioned when they first developed the seal it had no water at all being introduced into it, it was dry. He said it would still retain some water in the seal, and there is no way to cause damage from towing at houseboat speeds.

If anyone would know, it would be him... they produce and sell the seal.

Another good fact to know!!!

Great post. Never though about this stuff. I wonder if it hold true if your towing a faster than houseboat speed.