Trying to keep an old yamaha alive. What should I expect to

[chrismele]

I have an old yamaha 250 (1991) that I'm trying to keep alive. I'm thinking of having the carbs rebuilt, need reeds and new fuel pumps installed. What should I expect cost wise? I'm in nj. 2510

 

[DaleH]

Why rebiild or replace? Do they need it? I've never replaced a reed yet and have owned or serviced hundreds of OBs in my life. I only rebuld carbs when they need it. My bro's twin 1987 150s are still going.

Prop the boat correctly to NO MORE than 200 RPMs off max RPMs at WOT, perform full waterpump/thermostat/poppitt service every 2-3 seasons and decarb w/ Seafoam every 50-hours and new plugs each season. With her age, a sync & link by a pro is probably advisable.

 

[chrismele]

Thanks Dale. She's been giving me issues all summer. Around 4600 to 5300 she run poorly, fluctuates rpm and bogs. I've replaced all the fuel lines, new filter on the motor, new Racor in the bilge, new plugs and ran Dunk's decarb method. Last week I ran her on an aux 6 gal tank with new gas and she ran the same.

Local yamaha guy ran it a while back and said she needs new reeds as she vibrates a lot at idle / low rpm. I don't think he wants to work on this old of a motor. When I pull her for the season I'll check compression..... If good I'll put some work into her.

 

[DaleH]

If it was the reeds she wouldn't run at all. Sounds to me like she just needs a good thorough carb cleaning and tune up ...

 

[chrismele]

Dale
When you say to give the carbs a good cleaning, do you think I should rebuild them or use a spray? Also what would you do to tune the motor?

 

[Kris360]

If it is fluctuating rpm, it could be a fuel starvation. I would rebuild the carbs and while doing it replace the fuel pumps, fuel pumps are cheap insurance to keep that engine alive .

 

[Spoons]

I agree with what Kris says. You need to clean and rebuild the carbs. The fuel pumps are cheap replacements.