90-S Fires... But not at the right time?!?

[Ranger01]

1964 Evinrude Star-flite 90-s. Model# 904935, serial# E03005. Having trouble getting spark, when referring to my manual the belt timing appeared to be correct but we were getting no spark, tested all the wires and all that for continuity and it was all good. It looked like the rotor wasnt pointing at the lead at the right time so we adjusted the distributor pulley so the mark lined up with the kill switch as suggested in my book. But upon further review we found that while we did obtain spark, the marks no longer lined up (obviously because the pulley was moved) so my question is, with the marks lined up there is no spark, with the marks no longer lined up, there is??? What’s going on here?

 

[WillyBWright]

Re: 90-S Fires... But not at the right time?!?

Changing timing shouldn't affect whether or not there is spark. You disturbed something. My guess is that the bracket was badly grounded and twisting the fasteners reestablished a ground. Remove it and clean the mounting surfaces and hardware. You might try adding ground wires between the distributor and heads to assure a good ground path where it's the most vital. All those gaskets and bolts ... it's not hard to lose ground on an older motor. Corrosion is everywhere.

 

[Ranger01]

Re: 90-S Fires... But not at the right time?!?

It seemed like the rotor wasnt getting to the contacts on the cap at the right time to cause a spark. Thus the reason we thought of moving it to make it. I would have thought a bad ground would have made itself evident when we were doing the continuity testing?

 

[seahorse5]

Re: 90-S Fires... But not at the right time?!?

A rare problem unless there is a lot of time on the motor is a worn keyway in the distributor shaft and pulley area. It can shear or even wear a large groove and will make the rotor point in the wrong area. If all else fails, remove the pulley and inspect.

 

[Ranger01]

Re: 90-S Fires... But not at the right time?!?

Unfortunatly i dont know the history of this motor except for what i can see myself when inspecting it. I have determined that obviously we can't leave the rotor pointing out of time, so we have to move it back. In doing so i will use some sand-paper or emory cloth to clean all the ground connections like Willy suggested. Seeing as how i have to pull the cap and breaker point plate off anyway i should just take a look at the keyway. What do i need to do to inspect this part? Pull the pully off? How do i do that?

 

[seahorse5]

Re: 90-S Fires... But not at the right time?!?

Originally posted by Ranger01:<br /> 1964 Evinrude Star-flite 90-s. ...the belt timing appeared to be correct ...so we adjusted the distributor pulley so the mark lined up with the kill switch as suggested in my book.

It's been a lot of years since I've worked on a 90hp, but if I remember correctly, the timing mark does not line up with the safety switch. That is for the magneto equipped engines, not ones with battery ignition distributors like your 90. Ahead of the switch, there should be a raised line across the bracket arm that should be lined up with the notch or red tooth on the distributor pulley.<br /><br />What manual are you using to set the belt timing?

 

[Ranger01]

Re: 90-S Fires... But not at the right time?!?

That's right about the timing marks. The reason we chose to move it was because we werent getting any spark with anything that we had tried so when we read about the magneto timing mark we tried that. Low and behold there was spark. But like i said, now the timing will be off. I wonder if it was possible that at some point the ignition system was changed? But i doubt this highly because that year that battery ignition system was the one on that motor. so once again i'm at a loss.<br /> I havent had a chance to clean everything up and line up my marks yet, i'm hoping that the onyl reason i got spark was because somthing was diturbed like willy suggested. But in my case hope hasnt been going a long way...

 

[Ranger01]

Re: 90-S Fires... But not at the right time?!?

Well guys, once again your advice had been invaluabe. I took the distributer pully off and aligned the red notch and line to the raised line on the bracket arm like it should be. I also used a piece of sandpaper and cleaned all the ground connections along with adding another ground wire that went straight to the block. Put it all back together and crossed my fingers. turned it over and there it was, a thick blue spark. needless to say, i was pretty happy. I couldnt have done it without your guys help! I'm sure i'll be back with some more questions as i tear into the lower unit in the up coming months. Thanks again.