yam 70b problems

[frankie]

I have a yam 70bhp engine which drops revs after about 10 mins, she runs fine at first but then significantly drops revs for no reason. Can anyone help me to identify the problem. cheers frankie

 

[vanner]

Re: yam 70b problems

maybe you are reaching a high tep limit and it is going to get home mode

 

[JB]

Re: yam 70b problems

Ahoy, Frankie

Welcome to iboats.

Could be a heat related failure in the ignition, dropping spark to one cylinder. Put her on the muffs and use a hair dryer (NOT a heat gun) to heat up the ignition parts. See if you can reproduce the problem.

 

[Ray Neudecker]

Re: yam 70b problems

jb is likely right on the target. Concentrate on the CDI since they can be an intermittent failure on the 3 cylinders.

 

[frankie]

Re: yam 70b problems

thanks mate i'll try that, boat is coming out of water today to be cleaned so i'll be able to have a good look inside

 

[frankie]

Re: yam 70b problems

jb is likely right on the target. Concentrate on the CDI since they can be an intermittent failure on the 3 cylinders.

dont know if it's intermitent as it happened twice in a row, had to limp home last time thank god ive got a back up. cheers i will look into it
frankie

 

[frankie]

Re: yam 70b problems

hello there mate, can you tell me where i can find the cdi unit as i have looked through the manual and there is no mention of it. i'd be gratefull if you can help.
frankie