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I have an older Johnson 70hp that's giving me trouble seems like a fuel issue. Was running fine up until recently. It's a very clean motor for the most part. I'm looking for a good person or place I could take it to have it looked at or repaired without breaking the bank. I tried the search feature but didn't turn up much.
Before taking it to a mechanic I would Seafoam (and DeepCreep) the engine. If you've done that, then check and tighten the low pressure side of the fuel system to see if it is sucking air in anywhere (an outboard has numerous fittings that can go bad). Those are the two most common problems I've seen. Wouldn't hurt to see that all plugs are getting fire.
Joey Woodly over on County Road 4 by the Oyster Bay Bridge has been fair to me on pricing (251-981-4348).
If it's bogging down when trying to accelerate, check your fuel bulb and lines, especially if they're older. The older rubber bulbs and fuel lines don't like the new ethanol blend fuels. The bulb and hoses tend to deteriorate from the inside out and turn to a gummy substance. There are now ethanol rated bulbs and lines (they will be marked "ethanol resistant" or something along those lines. I had a bass boat that, one day while heading up the river, wanted to bog down every time I tried to get up on plane. Got to doing some research online and changed the fuel bulb/line from the fuel tank to the engine. Put it back in the water the next day, and it ran like a brand new engine.
Bulb and line is brand new. I know what you mean though.Quote:
Originally Posted by hammerhead
Did it run ok before replacing the bulb and line??? Could it be a bad bulb/line!!
if you run ethanol gas I'd try the SeaFoam.
If you can find no ethanol gas I'd switch to it. It's actually not to hard to find. Running no ethanol is much better for the fuel system.
If you try all of these things with no luck, and it will run momentarily with starting fluid, it's likely the fuel pump. I've seen this twice on old Johnson 70 outboards. Fuel pump is sort of a misnomer. It's really just a reed type check valve. They are very simple to replace.
Do you have a fuel water separator? If you do, change the cartridge. If no, install one. It helps with the ethanol problem.
Check for water in your tank, is it portable tank or permanent install? Can you get to it?
If you put in a fuel water separator and run the boat for 30 minutes or so, then pull the cartridge and pour it out into a bucket. If there is water & gunk in the gas, you know your fuel tank is contaminated.
Check the connections on the new lines & bulb make sure they are tight.
Next, check any fuel bulbs/filters under the cowling. Sometimes they get filled with water & junk and it will act like you describe.
Spray the carbs with carb cleaner.
Depending on the size of the fuel tank, put one or two cans of SeaFoam in the tank, run it for a while.
If none of this fixes it, you either have a bad fuel pump or (more likely) your carbs need cleaning (most likely a clogged high speed jet that the Seafoam cant clear).
Given the age of the motor, a complete carb rebuild, replacing all the jets, gaskets and seals with modern ethanol-resistant ones, would not hurt.
I used to use Rod & Jan's at ICC Marine, on the north side of the HWY 59 Bridge. But that was 15 years ago. Not sure if they are still in business or who owns it.
Is this problem intermittent, or does the motor not run at all?