johnson 1985 115hp ob ideal but wont run when in gear?

[licketdsplit756]

got spark to all plugs rebuilt carbs. starts fine aliitle rough at idle. takes 2 seconds to start so i think fireing fine.twc3 oil getting plenty. gas 93 octane. it has set for 4 yrs. checked ohms at stator/ rectifiers volts where nessasary.noticed the left 2 cyclinders seam to be running colder then the other 2. but there is spark there..doestnt seem as thow im running on all 4 cyclinders. they should all be warm im sure..when i put it in gear it just stalls. i can get a few feet with it. thats it.is there a diafram of something in the fuel system i might be missing...?? or compression whitch i havent checked. any advice i would appreciate. model j115tlcos

 

[jtexas]

Re: johnson 1985 115hp ob ideal but wont run when in gear?

Dies while idling in gear, before you give her any throttle?
Have you done a link & sync?
What are your idle RPMS?
Whats the compression?

do a cylinder drop test:
With the engine idling, pull and then disconnect each spark plug wire one at a time. RPM's should drop noticeably with a wire disconnected, otherwise that cylinder's not making power. Use a plastic spark plug boot tool to avoid electrocution.

Is the fuel line holding pressure (primer bulb still firm when the engine dies)? If so then fuel pump is unlikely to be the cause. If you can get it to run by manually pumping the primer bulb as you put it in gear, that would indicate a weak fuel pump.

Using any gas over 87 octane is a waste of money, IMHO - extra octane is only required by engines designed with high compression ratios.

 

[Dennisanoka]

Re: johnson 1985 115hp ob ideal but wont run when in gear?

First you don't need the high octane for your engine, others here will confirm that. Secondly, if you mean the gas has set for 4 yrs. get rid of it, or do you mean the engine has set for 4 years? If the engine has set for 4 years were the carbs re-built before or after the 4 yr. storage?

 

[ezeke]

Re: johnson 1985 115hp ob ideal but wont run when in gear?

I'm with those who want the compression test results. Do it first.

 

[licketdsplit756]

Re: johnson 1985 115hp ob ideal but wont run when in gear?

ill get back with this after a compression check. and no the buld is soft after it stalls. when you say firm no the bulb doesent get firm beond being able to squeeze it and tock both sides together. i can feel pressure there thats all. carbs have been rebuilt.

 

[jtexas]

Re: johnson 1985 115hp ob ideal but wont run when in gear?

The primer bulb should get firm when you pump it up - not quite hard as a tennis ball, but you shouldn't be able to touch the sides together. Listen for the sound of sucking air when you pump the bulb. If the bulb has been sitting around for 4 years, its time for a new one anyway - go ahead and spend the extra $7 or so for the BRP brand....the aftermarket primer bulbs don't have a great reputation for reliability.

Inspect all the fuel lines/fittings under the cowl for leaks while somebody squeezes the bulb.

If gas runs into the carb throats when you tilt the motor full up, the float valves are leaking.