70 HP 'rude, where's the adjustment for idle timing?

[jimogeek]

I've got a 1996, 70HP evinrude. It starts fine (a bit harder than it used to be, but acceptable), but once it's through with the fast start cycle, the RPMs drop from about 1100 and the engine cuts out. I've watched this with a timing light, and it's really not close-running about 5 degrees ATDC behind the specs. When in quick start mode, it runs at about 6 ATDC, and goes all the way to 18 ATDC when it 'kicks down'. The idle when it dies is around 600. The clymer shows an idle adjustment screw, it looks like the other end of the adjustment point for the high speed screw! Where the heck is the low idle timing adjustment? Is it the same screw? It doesn't have any noticable difference when I ajust it. It runs fine, usually when backing up or just shifting I have to give it a bit more throttle to keep the engine going, it's getting pretty darn annoying though and I want to get the engine running correctly. I'm still getting about 5500 rpm at wot.

 

[Hooty]

Re: 70 HP 'rude, where's the adjustment for idle timing?

There is no "low idle timing adjustment". Pick-up timing is done with the link & sync adjustment. The idle speed is adjusted by the idle speed adjustment screw and it sounds like it is idled to low. I think it should be idling at 700-750rpm in gear and in the water.<br /><br />c/6<br />Hooty

 

[mcginleyc]

Re: 70 HP 'rude, where's the adjustment for idle timing?

Hey I just did a link n sync on a 97 johnson 70 today in school (MMI). The idle fuel adjustment screw should be set 2 and 3/4 turns. This mean screwing all 3 idle screws (On the starboard side of carbs) in all the way and backing them off 2 and 3/4 turns. Then the motor should be run and the idel screws adjusted in 1/8 turn increments to select the highest RPM in the neutral range. The manual can explain it a little better, but 2 and 3/4 is where to start after you sync the linkeages. Good luck, that is a bullet proof engine!

 

[jimogeek]

Re: 70 HP 'rude, where's the adjustment for idle timing?

Thanks for replies! I feel much better knowing that there's no low end adjustment, it was driving me crazy! I'll go through the link 'n sync again and get everything dialed in. <br /><br />What controls the timing for the idle? If it's off by that much, how is adjusting the idle adjustment going to affect the timing?

 

[Hooty]

Re: 70 HP 'rude, where's the adjustment for idle timing?

I just do the link & sync and the wot timing and don't worry about the pick-up timing. <br /><br />c/6<br />Hooty