1968 9.5 looses RPM

[Lion hunter]

Re: 1968 9.5 looses RPM

Have you replaced all your hoses, whether they look good or not? Before you go drilling holes, run it with the cover off. If it runs the same drilling holes won't do any good. They pull plenty of air from behind the plastic plate on the front of the cowl. If it runs good with the cover off you mau have a bad exhaust gasket, or ot's not sealed right because of dirt.

 

[Viper2872]

Re: 1968 9.5 No Top End

Re: 1968 9.5 No Top End

I have replaced all the hoses from the tank all the way to the Carb. The motor is still cutting out on the top end. I took apart the carb and blew out what I could with a can of air. I can't see either of the jets to make sure they are clean. As long as I run the throttle at about half, I can maintain the RPM. Anything more than that and it starts Surging and dropping. If it goes too high, it completely starves and dies.

 

[Lion hunter]

Re: 1968 9.5 looses RPM

Did run with the cover off? It wasn't spitting fuel out of the carb was it?

 

[Rick.]

Re: 1968 9.5 looses RPM

You say your blowing passages clean with air. Are you using cab. cleaner and then air or just air? Your symptoms are that of a dirty carb. I am glad you replaced the all the hose as that would be suspect but I hate to say it but it sounds as though your high speed orifice needs cleaning. I had mine surging and it turned out to be the points were a wee bit wider gap that .020. The difference is that mine never stalled, just surged. Rick.

 

[Lion hunter]

Re: 1968 9.5 looses RPM

Agree with Rick...As simple as these motors are theres enough parts there to complicate things. Pretty well have to check point, carbs, spark, compression. Check everything and slowly narrow it down to the cause. There are alot of things that produce the same symptoms.

 

[Viper2872]

Re: 9.5 looses RPM

Re: 9.5 looses RPM

Finally I am pretty sure I have fixed it. I don't know where I read it but I figured I would try it. I pulled the carb back apart and flipped the top half upside down and found that the float wasn't level. I didn't replaced it but bent the bracket so the float would sit level. Then took it back out tonight and it ran like a champ. I started faster than it ever has before and ran without cutting out or dying or anything. Thank you guys for all your help.