Outboard diagnosis?

Got a ’97 Johnson 70HP. Periodically it doesn’t want to accelerate, like there is a fuel restriction or possibly an air leak in the line. The fuel line, bulb, etc., are only a year old and I checked all the clamp/connections. I run sea foam on a regular basis also. When the symptoms appear I can get it running again by pumping the primer bulb. The symptoms appear sometimes weeks apart and I ran it almost every week all summer and fall. The last time out (Dec 6) it was doing the same thing. Anyone have a starting point or anything I can check before (last resort) taking it the shop?

i use to work on johnson/ evinrude and i would start by cleaning the carbs and if that dont work i would replace the fuel line from the tank to the motor primer bulb and all i would think that should take care of your problem the little check balls in your primer bulb could be shot and letting fuel flow back threw the line and the carbs could have a piece of something floating around in there it never hurts to take and clean them and maybe also to a carb kit hope this helps ya out

For what they cost I’d start with a new primer bulb. Only a year old don’t mean much nowadays.
We’re a throw away society as that’s how stuff is being manufactured.

If it was me and I checked for airleaks and if it runs fine pumping the bulb I would look at the fuel pump since you replaced every thing else. I myself don`t beleive it is a carb issue other wise pumping the bulb would not make a drastic difference. In my Opinion

Edited to add… Unless it is a 4 stroke then carbs could be an issue. Especially on exceleration.

Mr. hook: If your fuel line from the tank is say 3-4 yrs. old,or older I’d replace it with a good quality line.I like the OMC, seems to be the best product out there. Welcome to IDO.

the fuel line is a good place to start but it could very well be a carb problem it depends on if the primer bulb is going soft or not before he pumps it dose just pushing the choke help any

I agree with replacing the primer bulb. I had to replace mine on my motor after only one year. It was a bad bulb and after replacing it again it worked great.
It was a very cheap fix.

You didn’t say if you had a built-in tank or portable but on built-in tanks there is a check-valve in the nipple coming out of the tank.I’ve had one of those gum up on me,
you can unscrew the nipple and punch it out with a screwdriver.

Welcome aboard. See what a great bunch of folks are out there?

Hey, many thanks to the guys that responded. I’ll try another fuel line/primer bulb. And yes, it is a built in tank. I’ll also check the valve in the tank. Didn’t even realize it had one. Nothing worse than boat and motor problems. Takes the fun right out of the fun. I’ll probably check the carbs also since there will likely be time to do it before we see a lot of open water again. Likely time to replace the spark plugs too. Don’t think I did that last spring and they are usually fouled in a year’s time. Thanks again.

Borrow a 6 gal. can from a fishing buddy, use his hose and mix up some fresh gas, if you still have a problem with the remote tank and different hose then it’s time to look under the hood.