110hp Johnson v4 with VRO won't keep running

I accidentally posted this in the wrong section, yesterday.

My 1988 (I think) Johnson v4 with VRO won't keep running. This started with engine failure while underway, then it would start again & run fine for a while. Coil & some electronics changed by mechanics who "knew exactly what was wrong.) Installed new fuel filter yesterday.

I'm leaning to fuel pump, since it would keep running, roughly, if the primer bulb was continuously pumped.

Any thoughts & expertise greatly appreciated.

Re: 110hp Johnson v4 with VRO won't keep running

You are pointed in the right direction - fuel issue. I'd look for air leaks in the fuel line connections before I throw parts at it. Also I would convert to a pre mix system & get rid of the VRO - and I have a pair of 1987s.

Re: 110hp Johnson v4 with VRO won't keep running

If you can keep it running by constantly priming the hose bulb, it could very well could be a weak fuel pump. Those VRO pumps are pretty pricey, at around $410 or so. The newer ones are pretty reliable anymore. Rough running could be a spark plug miss or problem with the fuel passages in the carbs. Check the spark while running with an inductive timing light-all 4 plugs.

Re: 110hp Johnson v4 with VRO won't keep running

Windjamer said:

I accidentally posted this in the wrong section, yesterday.

My 1988 (I think) Johnson v4 with VRO won't keep running. This started with engine failure while underway, then it would start again & run fine for a while. Coil & some electronics changed by mechanics who "knew exactly what was wrong.) Installed new fuel filter yesterday.

I'm leaning to fuel pump, since it would keep running, roughly, if the primer bulb was continuously pumped.

Any thoughts & expertise greatly appreciated.

Click to expand...

I had a very similar problem years ago. Same symptoms, similar work by "expert" mechanics.

Right after I acquired the boat it I took it to a local 'expert' for routine maintenance and a tune up.

I got the boat back, she started and ran fine at low throttle speeds, as soon as I tried to open her up she would sputter and stall out. She'd start up again just fine.

I took her back to the "Expert" and he said it must be the coils etc.

He replaced the coils and some other electrical bits. I'm back on the lake - same problems.

Turned out to be metal shavings in the carb(s?)

I took the boat to another dealer who suspected a fuel problem rather than electrical, he checked the carb and found metal shavings. Probably for the initial tune-up.

I paid the dealer for a tune-up and sent a letter to the "expert" explaining why I put a stop payment on the check for the coils and electrical components adding I'd be willing to meet him in Small claims court if he cared to sue.

So my advice, have an independent expert check the carbs.