One for the Experts.....

[rsimmons42]

OK, purchased boat about a two months ago and took it out, boat would idle but would not run when put in gear. Engine is a 1977 Johnson 70 hp(Model 70EL77S) I then completely rebuilt the carbs, replaced the fuel pump, replaced the fuel lines, and replaced the rectifier. Did a sink and link as best I could. Took the boat out last weekend. Was able to get the boat up to a plane, but would only travel at 29-30 mph (gps) Boat is a 1989 16' Sunbird. Don't know if this is a decent speed for this engine and boat. The engine sounds just a little bit rough. I looked at the plugs in it today and noticed that the plugs are Autolite 2634, I replaced them with Champion L77JC4's. Now here is the Question(s).

Is the Autolite plug compatable?

If not could this of caused the problems.

Compression is #120 all three cylinders, and the spark was about 3/4 of a inch with the new plugs.

Please let me know what you can.....Thanks

 

[Dhadley]

Re: One for the Experts.....

Champion plugs only. It may or may not be the issue.

You'll want to do a good job on the sync-n-link. If the linkages aren't going all the way it could cause a lack of power. Also the timing being off could be an issue.