Reply
 
Thread Tools Search this Thread
 
Old 18 April 2005, 07:06   #1
Member
 
Country: France
Town: PARIS
Length: 7m +
Join Date: Apr 2005
Posts: 14
Yanmar outdrive and trouble

Hi,

I have found in the forum Threads about outdrive. in one of them I've readen : "I just spoke with another Yanmar owner who's suffered a cracked block this week. He's done some investigation into the problem and found that they all(?) crack in the same place - near an engine mounting. The mounting in question uses three bolts, whereas the mounting on the other side uses four bolts. Also, he tell's me that there are internal oil colling galleries running close to this point. Apparently four bolts could have been used, but Yanmar have mounted some of the external components close by. I don't know if Yamaha do the same. He also tells me that builders such as Mark Pasco move these components and modify the mounting."

This thread was in 2003/2004, Is there still troubles with Yanmar outdrive ?

Thank

Phil
__________________

__________________
phildefer is offline   Reply With Quote
Old 18 April 2005, 07:18   #2
Member
 
Country: Canada
Town: Newfoundland
Length: no boat
Join Date: May 2000
Posts: 2,097
There are extensively reported problems with the Yanmar 300hp and Bravo 3 and 3x outdrive. Particularly on bigger boats. Do a search for 'Bravo 3' and you'll find lots of threads.
__________________

__________________
Out of the fog......
Alan is offline   Reply With Quote
Old 18 April 2005, 07:51   #3
Member
 
Country: Ireland
Town: Carigaline/Baltimore
Boat name: XS-600
Make: XS-Ribs
Length: 6m +
Engine: Merc Optimax 150 XL
Join Date: Feb 2004
Posts: 682
Has anybody got any experience of the new Bravo 3XR drive. Apparently they have solved the associated Yanmar troubles with this one.

http://www.mercurymarine.com/_bravo_xr
__________________
Steve G
If In Doubt, Go Flat Out!!
swginn is offline   Reply With Quote
Old 18 April 2005, 08:32   #4
Member
 
Country: UK - Wales
Town: swansea
Boat name: Too Blue
Make: BLANK
Length: 8m +
Engine: Suzuki DT225
Join Date: Mar 2004
Posts: 12,791
Quote:
Originally Posted by Alan
There are extensively reported problems with the Yanmar 300hp and Bravo 3 and 3x outdrive. Particularly on bigger boats. Do a search for 'Bravo 3' and you'll find lots of threads.

I know there are probs with the bigger 300hp - the drives can't handle the torque but what about the 240hp??? Would have thought it would be easier on the drive!!!
__________________
codprawn is offline   Reply With Quote
Old 18 April 2005, 12:59   #5
Member
 
Country: UK - Scotland
Make: HumberOceanOffshore
Length: 8m +
Engine: Volvo KAD300/DPX
Join Date: Oct 2002
Posts: 4,962
There might just be a bit of, 'It ain't what you do, it's the way that you do it.' involved too.
__________________
JW.
jwalker is offline   Reply With Quote
Old 18 April 2005, 14:54   #6
JIY
Member
 
Country: UK - Scotland
Town: Largs
Boat name: Spitfire
Make: XS850
Length: 8m +
Engine: 2 x 200 Verado
MMSI: 235905304
Join Date: May 2004
Posts: 174
My boat has the 250hp yanmar coupled to the Bravo3x. I chose the 250hp, as there seem to have been few problems experienced with drive failures on engines of this size or less.

I did experience a failure of the universal coupling joint at 280 hours - one of the needle bearings in the joint had run dry and failed. On investigation it turned out that a normal Bravo 3 had been fitted to my boat, rather than a Bravo 3x. Laurence Lock from Barnet Marine very quickly remedied this and a brand new Bravo3x was fitted to the boat. The Yanmar engine has now run 580 trouble free hours, the new leg 300 trouble free hours.

The problem with bigger hp engines seems to be related to torque and also overheating. RIBs spend much more time out of the water than other motor boats, so the legs themselves (or at least the gear casings) are often out of the water, and hence lack natural cooling (this is why Redbay fit a shower tube above outdrives). Also, leaping in and out of the water with large amounts of torque is inevitably stressful on gearing and drive shafts.

I'm no engineer, but this is the gist of what the professionals have told me!
__________________
JIY is offline   Reply With Quote
Old 24 April 2005, 09:27   #7
Member
 
Country: France
Town: PARIS
Length: 7m +
Join Date: Apr 2005
Posts: 14
Quote:
Originally Posted by codprawn
I know there are probs with the bigger 300hp - the drives can't handle the torque but what about the 240hp??? Would have thought it would be easier on the drive!!!
No bad experiences with yanmar 240 hp and Bravo 2 or 3 ?

Thank
__________________
phildefer is offline   Reply With Quote
Old 24 April 2005, 14:05   #8
Member
 
Country: UK - England
Town: Farnborough
Boat name: Eleven
Make: Arrow
Length: 8m +
Engine: 557cu, 700hp
Join Date: Jul 2003
Posts: 1,255
Out of interest, what is the peak torque on a 300hp yanmar?
__________________
Matt is offline   Reply With Quote
Old 24 April 2005, 15:14   #9
Member
 
ribraff's Avatar
 
Country: UK - England
Town: Dartmouth
Length: 6m +
Join Date: Feb 2003
Posts: 1,209
Yanmar 315

mmm, i think a lot of it has to do with the strength of engine beds and flex in the hulls.
__________________
Hypalon Tubes built in-house,retubing, repairs, Accessories
www.ribtube.co.uk
ribraff is offline   Reply With Quote
Old 24 April 2005, 15:23   #10
Member
 
Country: UK - England
Town: Farnborough
Boat name: Eleven
Make: Arrow
Length: 8m +
Engine: 557cu, 700hp
Join Date: Jul 2003
Posts: 1,255
Yeh, I understand that's the issue with the block failures, I was interested from the perspective of drives failing
__________________

__________________
Matt is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 09:18.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.