timing off/high speed miss???????????

[008wagon]

my 1989 60 horse johnson has been having a very intermint high speed miss/kick. i took it to my mechanic he said that the timing was off 10 degrees at idle and 5 degrees at full throttle. would this cause my miss? how would it have got out of time? thanks

 

[008wagon]

Re: timing off/high speed miss???????????

anyone?

 

[levi_tsk]

Re: timing off/high speed miss???????????

what he may have meant is that it needed a link and sync these engine dont really "go out of time " but if the carb(s) have been removed the linkage between the spark advance and the carbs can be out of ajustment once they are reassembled ... theres a link in the top secret file on how to do it and all you need is a timing light and someone to hit the key for you

 

[levi_tsk]

Re: timing off/high speed miss???????????

and yes if it spit back a little at idle and at WOT this was the cause...

 

[Midnight Krawler]

Re: timing off/high speed miss???????????

A common cause for a high speed miss: A lot of good mechanic will miss this one and throw expensive parts at the motor trying to fix it. It sounds like your shift dogs in the lower unit are worn and it is jumping out of gear. It will only do this when under load, so troubleshooting can be difficult. If the "miss" is more like a kick or a bang then this is usually the cause.

 

[008wagon]

Re: timing off/high speed miss???????????

he already tore the lower unit apart and said there is no way it was jumping out of gear

 

[levi_tsk]

Re: timing off/high speed miss???????????

i reiterate what i said before ..........

 

[008wagon]

Re: timing off/high speed miss???????????

would the timing being off cause it to miss very hard at full throttle though. when it was doing this it was like it was losing all power for a split second and the would come right back. could my timer base be bad? thanks

 

[008wagon]

Re: timing off/high speed miss???????????

do timer bases just go bad all at once or do they slowy act up?

 

[Jogin]

Re: timing off/high speed miss???????????

short of there being damage caused to the timer base or flywheel they generally don't go bad. I would still check the sync and link, but if you feel the timing is off it is possible for the jam nut on the timing screw to loosen and over advance your timing. I have also seen in other applications where a carb can be dumping too much fuel into the cylinder and causing it to miss intermittently due to the plug getting too wet, so this could definitely be changed by a sync and link or even a high speed adjustment.

 

[viciousfishes]

Re: timing off/high speed miss???????????

Where is the link the goes to the spark advance from the carb? This sounds exactly like what my motor is doing and Im trying desperatly to get to the bottom of it.

 

[Jogin]

Re: timing off/high speed miss???????????

it is not a link from spark advance and carb, it is just that you may have the synchronization linkage for your carb or carbs with your throttle mis adjusted, I believe there is a sticky on the forums that goes over it with you, also your carb may need a high and low speed adjustment which generally should be done in water so it will then be under a load, if it is not something you can figure out on your own, i would suggest bringing it in to a mechanic and ask them to adjust the carb and make sure that the sync and link is where it should be

 

[008wagon]

Re: timing off/high speed miss???????????

he said my timing was advanced by 10 degrees at idle and 5 and full throttle . just trying to figure out how this would have happened .he thaught my the timer base was worn some and threw it out of time?but wasn't sure or something come loose. it has been fouling the plugs lately though too.

 

[Jogin]

Re: timing off/high speed miss???????????

sounds like you are running a rich condition based on your plugs being fouled, if that system has the means of timing it that i think it should be off the same at idle and WOT. I am not saying your mechanic is lying to you but I am also saying that he could be too, I would bring it to a different mechanic to have look at it to get a second opinion, also do not tell that mechanic what your other mechanic had said so you can get a proper diagnosis with out any preconceived notions.

 

[008wagon]

Re: timing off/high speed miss???????????

it was also smoking quite a bit at trolling speeds .this is the thrid mechanic it has been to and the only one that seems to trouble shoot instead of just throwing parts at it. so i guess i was just wondering if the timing being off would cause it to miss? thanks