Tech. question about 72 Evinrude 125 timing

[John Bett]

Hello, I have a question about my 72 125 Evinrude. After finding that my PULSE pack was bad, I converted the ignition to the points type from a '69 85hp motor I have. I switched the whole ignition system, even the alternator. It runs great, but I am wondering about something. On the stock 125's PULSE pack (breakerless) ignition, the timing is set with a timing light at the marks on the flywheel. But on the breaker type system which came off of the 85hp, you simply ajust the distributor advance to a mark near the cap and a specific mark on the throttle. My question is, should I be using the timing light to time it now since I converted it? Will it matter? and why are there 2 ways to time the motor since the differences are small except for how the spark is obtained.<br />Thank you all.

 

[John Bett]

Re: Tech. question about 72 Evinrude 125 timing

Well, let me reiderate my question. With a little more cubic inches and a slightly larger carburator bore difference between the 125 and the 85hp evinrudes, and with the spark advance being controled the same way between both and the only difference that I can see being the way the spark is obtained (points or sensor), why have the 125 require a timing light? Whew..

 

[slyshar3]

Re: Tech. question about 72 Evinrude 125 timing

If this thing runs great, my advice is not to mess with it. I have the same motor and it has had an intermittent miss since the day I got it. It is nickle and diming me to death, and I am about to blow it up.

 

[R.Johnson]

Re: Tech. question about 72 Evinrude 125 timing

You time both engines with a timing light. Even though you changed ignition systems, the timing has to be in sync. with crakshaft position. The timing would remain the same.

 

[John Bett]

Re: Tech. question about 72 Evinrude 125 timing

Dear R Johnson. Thanks for advice.<br />72 Rude, Dont give up. Your 125 is really nifty and hydroelectric shift is nice when maintained propperly. Have you removed all of the individual spark plug wires and coil wire and tested resistance on them and compaired to new ones? I had a couple with high resistance and actually removed the crimped on ends and found corosion and trimmed back about 1/2 inch and recrimped the end caps on and it fired hot on all. If your wires are high resistance and corroded that might be why your motor runs good a while on brand new plugs, but then starts missing.

 

[slyshar3]

Re: Tech. question about 72 Evinrude 125 timing

Th resistance is = on all wires through the cap. Thanks for the support though.