Pliant

Ok so i have seen a lot of threads and have lived with the SX-M drive vibrating fairly hard on turn's left of right only...trimming is another world only at very high (high articulation) does the drive shrudder. So the drive is off and the knuckle's are as free and easy turning as one could hope for...that is not loaded.... so i cam across the below post and asked myself the question...could it be..i would just hate to throw away a good pair of joint's so i am asking for some input i really hate that damm vibration in the turn... so what shall it be... Toss out the old and in with the new????


http://www.*****************/boat-for...-wheel-cranked


The thing with our drive shaft bearing crosses (aka U-joints) is that when under power (for the majority of the time), we are pretty much nagivating straight forward.
This places the drive shaft geometry in a fairly straight alignment.
Unlike the automotive counterpart, there is minimal articulation.

What this means, is that the bearing "cap" and bearing cross "trunion" are contacting more so in the same location....... rather than a rolling needle bearing pattern where there is more articulation.
What we get is a wear groove that actually accelerates the wearing out of our bearing crosses.

They may still feel rather smooth, but may not be in good working order.
This is very likely the source of your vibration.
For the cost of replacement, it becomes the thing to do.

BUP

iTrader: (9)

I did not read all of your thread .Sorry about that.

Volvo Penta only recommends buying the complete assembly and not to change out just U-joints. Volvo claims they are all matched and come as a complete balance assembly plus do not want to compromise new U joins in old possible worn assemblies. Have no idea if this will help or not about your app and are you 100 % sure your U joints never been changed ?

I am not saying u can not change out just the U joints alone as I have as well many of times. If you order thru Volvo they do not have just U joints to sell for their input driveshafts to their dealers.

With that said I have heard thru some and some complaints that boat owners have reported vibrations even after brand new U joints only (not assemblies) were installed. Just saying.

BUP

iTrader: (9)

https://www.marinepartsexpress.com/b...P-44-1-5_1.pdf

here is one of the SB about some of it and possible help to maybe your cause

Pliant

Bup i do not know how to thankyou enough i have the 3855714 drive incredible.

BUP

iTrader: (9)

Your welcome, what is hard about posting OEM information is I can not post it - so I remember the Service bulletins & numbers off the top of head and then have to search for them if all possible thru google in which you can only find some. Then post that link up here.

If you can find Volvo Penta service bulletin 44-2-20 If I recall that has info about U - joints to that might helpful. .

All my reference and service manuals are in storage so thank whomever my memory is still somewhat good but I am getting old so that will only last for so long.

Again look for Volvo SB 44-2-20 if I recall correctly.

SB

iTrader: (1)

Here is one thing on it:
http://www.marinemechanic.com/volvo/sb-44-2-20.htm

BUP

iTrader: (9)

Thanks SB that is it, but I think the real Volvo SB had a bit more info about it. but that is the jist of it in the link you posted. I knew that SB had some info about U-joints.

We mark all positons for the U-joints , yokes and related parts before disassembly then upon reassembly we put it all back in the exact position even if new parts being installed - they all go back in the same exact positions so we hopefully eliminate any unbalances.

IMO I think that is were some of the complaints come from after new U-joints alone were installed. But it is very wise to inspect all yokes and other related parts for wear, cracks and any out of rounds.

waterproof lipstick works great for marking all parts Just saying.

Pliant

BUP i again thank you for your input...I owe you more than a few beer's.

BUP

iTrader: (9)

Whatever came about this ? Also can you tell me what year you have here along with your engine model number.

Also can I get more pics of your U joints Thanks.

BUP

iTrader: (9)

In your post number 1 you have a link listed in blue - what is that link to ? Can you direct me to it and or any other links about this. I have a reason and I will tell you later. THANKS.