yamaha 9.9 4-stroke problems

[derekjl]

Sent my Yamaha 9.9 4-stroke off to have its annual service only to be told that it had dropped a valve and would cost £3000 (yes, that's three thousand...) to fix, or I could have a nice new one for £2200. Both options are a bit out of my league - so has anyone else had a similar problem and is it fixable?
Lets face it, if my Land Rover dropped a valve, I'd be able to re-build the head with few problems, but are outboards really such a different world?

 

[No Regrets]

Given the price of Jap spares, this is possible.

Ask exactly which parts are damaged though. It might only need a valve, piston and the barrell cleaned up. (Plus gaskets and labour)

 

[boatbuilder]

The problem with yam 9.9's is the corrosion . Try to find an engine that the leg has corroded. Use this to rebuild your power head.
You will need lots of WD40 and a hot air gun to take it apart.
Look in the multihull world as they are the engines of choice.

 

[Clyde_Wanderer]

First question here is, Was it running ok when you last use it, or did it give up the ghost on you.
If it was running ok last time, then I cant see how it would drop a valve while laying up.
Is it one of the older white ones with the belt on the flywheel?
If you can repair a dropped valve on A landrover then you should be capable of at least stripping it down yourself, infact you would only need to remove the rocker cover to verify a dropped valve, usually when a valve drops the engine will stop emediatly which helps to lessen any potential damage, so all might not be that bad, get yer sleeves rolled up, take pics as you go along to help in the rebuild and some notes will also help.

 

[Inselaffe]

Surely if it had dropped a valve you would have noticed!
From your post it seems that you sent it off just for a normal service & then they said that it had dropped a valve? This don't make no sense to me.
Or did you send it off because it had a big problem?
I cannot recommend this Clymer manual enough, it will tell you (almost) everything.

http://www.amazon.co.uk/Yamaha-9-9-100-4...7003&sr=8-1

I was recommended this through (where else?) this great forum & it has been a great help.

Good luck

PS I have a 1990 F9.9AM model Yamaha 9.9 4-stroke (white)

 

[Haven't-a-Clue]

Sounds VERY suspicious to me! /forums/images/graemlins/mad.gif Get it back from them and see if you can GENTLY turn it over. FWIW, it might have burnt out a valve, easy enough to rectify, most important, get it BACK from them. Where are you, 'cos there's bound to be someone 'round this forum who'd help.

 

[Spyro]

Can't understand why they would give the option of a repair at £3000 when a new one would be £2200. Sounds like they are just trying to sell you a new engine.

 

[derekjl]

To be fair, I powered it up to get some juice into the batteries while rigging the hoist to drop it into the dinghy - while I was doing this it went clunk clunk and then stopped dead - so it was delivered to the service shed already knackered - they didn't break it themselves. It is jammed solid, won't move at all, which is consistant with a valve dropping and then jamming against the top of the piston. Its a 2002 model with electric everything, so I'm loathe to junk it....

Right, time to order that manual and get the spanners out, methinks - thanks for the comments.

PS: I do also have an old white one with serious corrosion on the transom clamps and engine mounts, however the long (possibly extra long) leg and high thrust prop are fine.