Before Posting, Please Read Our Posting Guidelines Below.
1. Use the full 4 digit year for everything you are asking your question about. Example: 1962, 1988, 2000, 2011 2. Include the correct name of your Whaler model. Example: Montauk 17, Montauk 170, Outrage 26, Outrage 260 3. Include the length when necessary. Example: 16, 17, 18, 20, 22 4. Do not post your email address anywhere on this site as it is already in your user profile.
Does anyone have any suggestions on why my 1989 Johnson 70 HP will idle fine in neutral but will shut off once I try to put into gear? I can be idling in neutral and go to full throttle okay but motor will die if I don't drop the hammer right out of the hole. Runs fine wide open and when not pushing boat but kills in low throttle when trying to trailer the boat. It runs perfect with muffs hooked to it at the house but once it trys to push the boat, it dies. Any help would be great.
My first guess would be a fuel issue.
Check your gas tank and filter for signs of water.
If the engine has been sitting for a while the carbs could also be gummed up from stale fuel.
An air leak in the fuel line or a kink could also be to blame but most likely it is fuel quality that is the problem.
I hope this helps.
WhalerEric wrote:
My first guess would be a fuel issue.
Check your gas tank and filter for signs of water.
If the engine has been sitting for a while the carbs could also be gummed up from stale fuel.
An air leak in the fuel line or a kink could also be to blame but most likely it is fuel quality that is the problem.
I hope this helps.
X2....sounds like a fuel / carb issue to me.
Cliff
1966 13' Sport with a 1993 40hp Yamaha 2 Smoker
Larry, I had the same 1989 Johnson 70, and had EXACTLY the same symptoms. Nothing, but nothing, would make it idle for any extended period. It always ran great once you got over around 1500 RPM, but 20 or so seconds at idle, in gear, was all you got. I sort of got used to it, but never really got comfortable - very much a pain when docking.
I rebuilt the carbs, including the core plugs, did a full link and sync, changed out the fuel pump, experimented with different idle jetting, decarbed the motor, you name it. I came to believe that's just the way it is for some of these motors. Great motor otherwise!
Your engine should run properly. The 3cyl -J70 has been around a long time. If it does not idle, there is a problem that can and should be fixed.
In other words,
Fix it... don't risk wrecking your motor. (lean means no oil to your cylinders)
If you aren't willing or capable, take it to a tech.
Start by doing a compression test and post your numbers. A big part of the reason it runs better on the muffs than in the water is because the exhaust backpressure is different.
