Is this a rumor or true?

[turbodriven]

I've got a Mercruiser/Alpha 1 setup and here in Florida the water levels can get a bit low at times. So when approaching a portion of water that is 2 feet or less (under the keel) I made it a habit to raise the outdrive up and propulse through with the little bit of thrust that a raised outdrive gives you.

Someone today told me that that is a BIG no no. He said that the u-joint get's worn at an expotential rate when run "at that angle". He also said "he learned the hard way" when he had to replace his after one season from doing that.

Any truth to this? This is my first boat and it's been a "learn the hard way" first season for me with a lot of things. I'd hate for this to be another.

 

[Don S]

Re: Is this a rumor or true?

IF you have the drive ALL the way up till it stops, it will destroy a lot of very expensive parts.
Running at low rpm (Below 1200) with it up above trim but the prop still in the water where it will do some good, can be tolerated on occasion. But a steady diet of high trim will damage the gimbal bearing and ujoints just because of the extra angle they weren't designed to run at at high rpm. Even high rpm (FULL) turns will make new ujoints sing and age quickly.

 

[ziggy]

Re: Is this a rumor or true?

just think about what a u-joint does. that will answer yer question. if it's at an extreme angle it will not like that and ya can expect to replace earlieier than usuall.
personaly, i've run my trisonic at 5k, trimed up too high. (wot 4400 perhaps, opps) i know, don't dog me. many years ago when i wasn't hip and i was a yougster. trimed that baby up. i got a modle 1 drive with the only the trailer mode operational. so i can trim wherever i want. includein too high. so far that aint' made much difference. my boat is toast. so who cares. there anit nothin not spent about my toy. be carefull with yers. ya will be replacein u joints if yer not carefull. think about what will happen if the ujoint goes. what else will it take out. $$$$$$

 

[turbodriven]

Re: Is this a rumor or true?

that's the thing... it seems to me that when the outdrive is raised that the u-joint is actually at less of an angle. That would create less stress on the joint, not more. Maybe I'm looking at the design wrong?

 

[Don S]

Re: Is this a rumor or true?

that's the thing... it seems to me that when the outdrive is raised that the u-joint is actually at less of an angle. That would create less stress on the joint, not more. Maybe I'm looking at the design wrong?

Yep, you're looking at it all wrong.

 

[ziggy]

Re: Is this a rumor or true?

dons. please correct me if i'm wrong. i feel that my model1 is at a negitive angele when trimed full down. the u'joint is bent down and at an angle. if i'm trimed up a bit i'm straight with the joint. up, past that is at an up angle on the joint. i can go past a point of no return where i get to tight on the u-joint and run the ristk of destroyin it....is that what yer talkin about tubodrivin?

 

[Boomyal]

Re: Is this a rumor or true?

How's come, you suppose, that Mercury does not use a Constant Velocity Joint instead of U-Joints?

 

[dodge1971340]

Re: Is this a rumor or true?

Hi! Turbo D. You are looking wrong your setup is a strait shot with your drive shaft into your motor coupler that's why they make a tool to line it all up when you put it together. but the universals are there for when you are under power and you you move your trim up and down, Kinda like a car when it goes up and down the rear end moves up and down and the universals are there so you don't rip your drive shaft out. but with your trim up that far for a long period of time like Don said you will rip the gimble bearing out and universals. and ran with those bad you will do damage to the drive its self. If you do it do it at low rpms and not for a long period of time. Hope we helped Good luck to ya!! 8) Dodge

 

[djvan]

Re: Is this a rumor or true?

We have a lake (my favorite lake) that has two parts a small end and a big end, connected by the "narrows". This is a no wake zone about 300 yards long. It is also shallow for most of the way. This requires me to trim up quite a bit. I have learned how much I have to trim up and keep it to a minimum. That being said I have been doing this for 5 years at least 4 times a week (June thru September). I have had to replace the gimble bearing but not the u joints yet. I probably just jinxed myself and will need to replace them this fall during winterization. But I don't notice them clicking yet.

HTH's

DougV>

 

[turbodriven]

Re: Is this a rumor or true?

What are the signs that my U-joint and/or gimbal are going bad? Right now everything seems fine. No abnormal noise or vibration at idle, in gear that I can tell. At least out of the water where I can see/hear it best. I'm just curious so I can watch out for it in the future.

 

[AdamB]

Re: Is this a rumor or true?

When I first got my boat a few years ago with a 20 year old outdrive, I used to run her on the muffs with the drive all the way up. Then I was educated quick when the gimble started making nasty noise. The marina changed the gimbal but said my u-joints were still okay. I never rev'ed her when trimmed up (or on the muffs for that matter).

I've abused my boat for 3 seasons now, high revs, lots of skiier and tube pulling and knock on wood my u-joints are still fine. But that's probably because I stopped running her trimmed to trailering height.

 

[djvan]

Re: Is this a rumor or true?

My gimble sounded like it was "groaning" all the time not an alarming sound. I actually thought it was normal as I bought the boat used and it sounded like this from day one. Almost like a old 4x4 when locked in 4wd sounds. The u joints from what I understand "click" and get worse when turning and when trimmed up. Up north we winterize partially to prevent freezing our blocks and such. But you should consider doing annual maintenance (this involves removing the outdrive) so that you can inspect/grease the gimble bearing and u joints. Do a search on winterizing and you could probably read about it for hours.

DougV>