'89 Johnson 30 HP too small to tube with?

[PSMike]

Folks,

In your opinion, is an '89 Johnson 30HP tiller on a 16' Sylvan Super Snapper (with floor) too small a package to allow for pulling small kids on a single tube?

As my other recent post shows I think I may have busted some teeth on my gears from doing this 2nd time out with this (our new) boat. Some say it should not be a problem, others say you are only risking with such a small and old motor. I may have gambled and lost this time around. Any thoughts?

Thanks.

 

[wilde1j]

Re: '89 Johnson 30 HP too small to tube with?

Don't know the boat. If it's aluminum, should be OK. Fiberglass, probably not. In any case, hard to hurt the motor trying and you're not going to damage gear case no matter what, unless you hit rocks or logs.

 

[OBJ]

Re: '89 Johnson 30 HP too small to tube with?

Believe I'll have to side with the "risk side" Mike. Pulling anything behind the boat puts a lot of load on the engine.....even small ones on a tube. Although I would expect that the engine itself and not the gear case would go first. Any chance you could have struck an underwater object?

 

[jdsgrog]

Re: '89 Johnson 30 HP too small to tube with?

How do you know you busted some teeth on the gears? If you have a full load of people in the boat, it may be too small a motor. But I am not familiar with the boat. Have you considered re-propping the motor down a couple of pitch sizes?

 

[jdsgrog]

Re: '89 Johnson 30 HP too small to tube with?

ok, i looked at your other post and looked up your boat. I don't think a 30hp is too small for that boat unless you have a full load of people on board. But a few things come to mind:

1. I would really consider re-propping the motor as I said earlier.
2. You may want to consider smart tabs to get the boat up. I am assuming your setup is a tiller setup. That's a lot of weight in back. You'll end up plowing through the water and putting a lot of stress on the motor.

From you other post, I don't think it was pulling the tube with kids that broke the teeth. It sounds like you had a bad shift cable causing the motor to shift improperly.

 

[tashasdaddy]

Re: '89 Johnson 30 HP too small to tube with?

we use to pull skis, and tractor tubes with a 15 hp 1955 rude, 14ft 3/8" plywood boat. the 30 on an aluminum should do fine. the original ski boats of the late 50's. only had 35 hp motors on them.

 

[PSMike]

Re: '89 Johnson 30 HP too small to tube with?

Thanks for the advice folks,

The boat is aluminum and it came with one of those hydrofoil stabilizers so the front end hardly lifts up out of the water (this works really well). Boat is rated for 1100 lbs (650lbs with 40 HP) so myself and 3 kids under 10 years amounts to about 420 lbs so within the limits.

Must admit, on the maiden voyage, did run into a sand bar (but not with a jolt - only noticed when the water was churning up muck) and perhaps that sudden slow down may have resulted in the damage, or I sucked something in or hit a small rock.

One other asked about how I knew the gears were chipped - a reputable marina has looked at and found this out after taking apart (they test ran the boat first and checked with a stethescope first). I could really hear the ticking second time out so knew something was up.

I may take everyones advice part way and that is take the kids out but perhaps the heaviest of our kids has to wait for the next boat. It might be worth upgrading to a 40HP tiller in the future.

Thanks all. Great Forum.

 

[F_R]

Re: '89 Johnson 30 HP too small to tube with?

Thanks for the advice folks,

The boat is aluminum and it came with one of those hydrofoil stabilizers so the front end hardly lifts up out of the water (this works really well). Boat is rated for 1100 lbs (650lbs with 40 HP) so myself and 3 kids under 10 years amounts to about 420 lbs so within the limits.

Must admit, on the maiden voyage, did run into a sand bar (but not with a jolt - only noticed when the water was churning up muck) and perhaps that sudden slow down may have resulted in the damage, or I sucked something in or hit a small rock.

One other asked about how I knew the gears were chipped - a reputable marina has looked at and found this out after taking apart (they test ran the boat first and checked with a stethescope first). I could really hear the ticking second time out so knew something was up.

I may take everyones advice part way and that is take the kids out but perhaps the heaviest of our kids has to wait for the next boat. It might be worth upgrading to a 40HP tiller in the future.

Thanks all. Great Forum.

I don't buy the notion that overloading or hitting rocks has caused gear damage. I used to water ski frequently with mine, and it has ground up many a rock. But whatever....

 

[R.Johnson]

Re: '89 Johnson 30 HP too small to tube with?

FR: You don't buy into that rock's will damage a gearcase. I have seen many a gearcase that hit rock's once, and that was it, Once! A mississippi wing dam will make short work of most any gearcase. A half dozen damaged gearcase's in the shop on any monday morning was not uncommon.

 

[F_R]

Re: '89 Johnson 30 HP too small to tube with?

FR: You don't buy into that rock's will damage a gearcase. I have seen many a gearcase that hit rock's once, and that was it, Once! A mississippi wing dam will make short work of most any gearcase. A half dozen damaged gearcase's in the shop on any monday morning was not uncommon.

Well maybe it makes a difference how fast you are going. I'm talking about going slow where I know dang well there are rocks in the way. But I've clobbered a few at high speed too. Santa Fe or Suwanee rivers here in FL during the dry season are a couple of good places to try it. Lots of motors running around with no skegs.

 

[R.Johnson]

Re: '89 Johnson 30 HP too small to tube with?

An outboard is engineered to tolerate some impact, same as the family car. 10 to 15 MPH. above that, expect problem's, serious problem's. Measure a gearcase with the skeg broke off. I have that surface plate, and dial indicator you speak of, Not a piece of plate glass. 3" thick black granite. You will find that case way out of tolerance. The service manual will not give you that tolerance. I got those tolerance figure's from OMC tech service's back in the early 70's. A gearcase does not like being bent very much.