Yamaha Valve Adjustments

Dora~Jean

Active member
Any Yamaha F75, 80, 90 or 100 owners (all same motor) attempt to do the valve adjustments on them? Involves considerable disassembly including the flywheel, then purchasing 'calculated' shims to make up the difference measured vs specs on intake and exhaust valves. I'm about to do it just for the 'sheer pleasure' of learning more about my engines (2003 F80's) -- and -- I'm not crazy about the closest Yamaha mechanic/dealership.

Steve
 
Steve - I have a 2003 F80 with about 180 hours. I haven't done it yet but I've been considering it, so I'd sure be interested to hear how it goes. I have the same reservations about my local dealer. If you don't have a shop manual, there was a direct link to an online factory manual for a 2005 75 HP Yamaha posted last week, which should be the same basic power head. It was in the "Yamaha internal anodes" discussion. Good luck.

Jim
 
Jim,

Yes, I have a shop manual, bought it within weeks of bringing home my new boat. I've been burned in the past when trying to order them after they've gone out of print for my particular model.

I don't have reservations about doing the work, just wondering about the 'hidden' instructions that so often aren't in the manuals. I have about the same amount of hours, hearing ticking noises on startup that go away after a few seconds, just good to check per mfr recommendations. Also plan to sync the carbs right after. I'll post my observations.

Steve
 
Piece of cake mon! It is a superior system too boot. I came to prefer valve adjustments this way, over the lock-screw types that need more frequent services.
Best to actually buy a kit of shims, and the little adjuster thingy, before you tackle it though. I was lucky enough to have a long history with the same valve system (DOHC) on every motorcycle (high performance street bikes) ever owned... this system like I just mentioned, is not only more simple with less-moving-parts, but does not need much servicing!

I checked my 2000 F-115 a couple years ago, and all the clearances on all valves were exactly in tolerance, and needed NO adjustments even after 1300 hours of torturous use on the RedFox -- Wahoo! :D :thup

I bet I will have to do it this season though. :| I notice they tend to wear and the gaps widens, not the other way, and get tighter (a bad thing that could lead to burned-valves)! :cry:

Back when doing this inspection, I needed NOT to remove any "flywheel" it is much simpler than that. If I recall right, one does have to remove the pulleys on the cams (not a big deal and kind of 'innerestin anyway) :)

Go for it bub! :tux

Greg
 
Great catch Greg! I 're-read' the manual on the flywheel -- it said to remove the "flywheel magneto cover" -- big difference. I remember reading the many pages of this procedure and becoming overwhelmed thinking how complicated it is. Now that the time has come, re-reading it seriously, it's got a lot of fluff to repeat long procedures to just put a belt back on or cover or other minor item... you're right, should be a piece of cake. Thanks!

Steve
 
Well thanx for the feedback :thup another thing; you don't need to replace any gasketing at all either. Just a tiny bit of gorilla snot (silicone) in the corners, make sure it is free of dirt and oil, in the places you do ad sealant. :!:

Now, if it were like my old "Kawasaki GPZ 550": shims under buckets, then I would warn of a tough job involving critical timing and more tools and expertise. But it ain't --- go Yamaha! :beer
 
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