Reply
 
Thread Tools Search this Thread
 
Old 26 August 2015, 03:18   #1
Member
 
dogboy's Avatar
 
Country: UK - England
Town: taunton
Make: zodiac
Length: 3m +
Engine: 10hp
Join Date: Dec 2010
Posts: 40
reboring 2 strokes

I have been sibing for a few years now with my little zodiac futura and trusty yam 9.9 four, which feels like it will go on forever, but I am now feeling the need for a new experience. Probably in the form of a late 15HP two stroke of the yam/merc/mariner variety.

My question is, most of these are now getting on a bit at 10 years old, so how do they stand up mechanicaly and are many now in need of a rebore ?

As a teenager of the eighties I am used to owning hard ridden two stroke motorbikes, and their subsequent need for top end overhauls. So, are most of the 15hp outboards now soon to be needing this work.... or is it different with a boat engine ? These engines still command a fairly high price and a rebore on top of that makes them rather pricey I guess ! Any thoughts or experiences with this one ?
__________________

__________________
dogboy is offline   Reply With Quote
Old 26 August 2015, 03:50   #2
Member
 
Country: UK - England
Town: gloucestershire
Length: 4m +
Join Date: Nov 2012
Posts: 340
I too was around bikes during the 1980's RD & DT time and did my own maintenance .

I have this year split my 90's 2 stroke suzuki OB, a decoke, de-salt of waterways and light hone of barrel was all mine needed.

I guess a compression test before purchase of motor might help to decide.

Working on one should not hold any terrors for you, if you were used to 80's bikes.

Good luck.
__________________

__________________
camelgas is offline   Reply With Quote
Old 26 August 2015, 05:03   #3
Member
 
Country: UK - England
Town: East Anglia
Boat name: Nimrod II
Make: Aerotec 380
Length: 3m +
Engine: Suzuki DF20 EFI
Join Date: Nov 2007
Posts: 3,275
I've owned a large selection of sub 25hp 2-stroke outboards over the past 20yrs. Late 70s Suzukis & Yamaha, mid 80s Mariners, late 90s Mercury, early-mid 2000s Tohatsu, Mariner & Mercury. Sizes including 2/3.5/4/8/9.8/9.9/15/20/25hp. About a dozen outboards in all.

All bar two have been bought privately, half of them with no demo before buying, and they have been between 6 and 25yrs old at time of ownership.

Not one has suffered any issues related to engine condition, just routine service work and the odd carb gasket kit, perished hose, seized tilt lock etc.

It's my opinion that in general smaller leisure use outboards get very little use so suffer minimal wear.
__________________
Fenlander is offline   Reply With Quote
Old 26 August 2015, 07:01   #4
Member
 
Country: UK - England
Town: Retford
Boat name: Spy-sea-one
Make: Mercury
Length: 3m +
Engine: Suzuki Outboard/25/4
MMSI: 235074042
Join Date: Oct 2011
Posts: 3,564
last year i bought a 1999 Johnson 2st as a project not my best choice of engine but still, it had running problems which i new was down to a fuel pump issue got it home cleaned her up gear oil, 20 fuel pump re-firb kit new filter & plugs compression test thumb over holes blew it off put it on a zodiac 310 solid went like s--t off a shovel.
total cost 550.00.
as fenlander says private engines don't do a lot they usually suffer the lack of TLC and a good service once a year if used or not i always use wd 40 or similar to keep the salt away and a good quality grease.if buying secondhand see it running in and out of gear,pumping water ok and have a look at the gear oil, also if its tidy under the lid.
your right about the yam it will go on for ever.

cheers
__________________
jeffstevens763@g is offline   Reply With Quote
Old 26 August 2015, 15:40   #5
Member
 
dogboy's Avatar
 
Country: UK - England
Town: taunton
Make: zodiac
Length: 3m +
Engine: 10hp
Join Date: Dec 2010
Posts: 40
Thanks folks for your thoughts. So it would seem its a fairly safe bet then. I.m glad they don't need the regular rebuilds like the old yam DT's did. It was fun at the time, but these days I'm a touch to busy for regular strip downs.
__________________
dogboy is offline   Reply With Quote
Old 26 August 2015, 17:29   #6
Member
 
spartacus's Avatar
 
Country: UK - Scotland
Town: Aberdeenshire
Boat name: Sula
Make: Ribcraft 4.8m
Length: 4m +
Engine: Tohatsu 60hp + aux
MMSI: 235087213
Join Date: Jun 2007
Posts: 3,267
RIBase
Unlike a motorbike engine, 2-stroke outboards are likely to suffer seized head-bolts, so the old adage, if it ain't broke, don't fix it certainly applies. In addition, outboard gasket sets can be rediciously expensive. As suggested, check the compression and maintain a rigorous service regime and there should be no need to strip it down.
__________________
Is that with or without VAT?
spartacus is offline   Reply With Quote
Old 27 August 2015, 15:10   #7
Member
 
Country: UK - England
Town: bicester
Length: no boat
Engine: outboard only
Join Date: Feb 2009
Posts: 894
If you do need a re-bore after all, find F,J,Payne eynsham Oxon. when I worked they did all our re-bores on OBMs, and I have used them on big engines as well, blind boring or just a straight re-bore.
__________________
uncle al is offline   Reply With Quote
Old 27 August 2015, 16:07   #8
Spammer
 
Country: Canada
Town: Southern Ontario
Boat name: -Unknown-
Make: SeaMax
Length: 4m +
Engine: Merc/Minn Kota
Join Date: Mar 2012
Posts: 216
Yes, a wet/dry compression test tells it all. Unlike most bikes, outboards are water-cooled above 3 HP. Before buying, even though the seller may say all cylinders are with 10 Lbs of each other never believe. In addition to doing both a wet/dry compression test, using a good light source look into each plug opening and inspect the cylinder head. If there's any sparkling particles on them don't buy it. It's been overheated somewhere along the line.
__________________
Nightfisher is offline   Reply With Quote
Old 29 August 2015, 12:21   #9
Member
 
dogboy's Avatar
 
Country: UK - England
Town: taunton
Make: zodiac
Length: 3m +
Engine: 10hp
Join Date: Dec 2010
Posts: 40
Lots of useful information. Thanks again to all offering their advice.
__________________
dogboy is offline   Reply With Quote
Old 26 September 2015, 02:52   #10
Spammer
 
Country: Canada
Town: Southern Ontario
Boat name: -Unknown-
Make: SeaMax
Length: 4m +
Engine: Merc/Minn Kota
Join Date: Mar 2012
Posts: 216
Sure a reboring's necessary? I mean there is a way to to do it cheap and write. But one who has not done it before needs to on how its done, i.e. skone-pressure, number of turns per minute, number of times to work the skones or stones as some call'm from one-end to the other per minute..so there's a lot of counting involved and all cylinders must be the same. Then there's the rental of a micrometer to ensure diameter even-ness and to know what size rings to purchase. I did it twice, both times successful just really need to read and understand the importance of exact counts per cylinder.
__________________

__________________
Nightfisher 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 04:07.


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