Fuel flow problems with 87 Johnson 35 hp.

[kdc2000]

I have a 35 hp 1987 Johnson (military model AM35B-1). It stalls when I go from idle to slow speed. The few times I've been able to get it past this point it runs great. How can I test the fuel pump? It looks like it can easily be disassembled. If it doesn't pass the testing should it be rebuilt or is it better to just replace it?

 

[Solittle]

Re: Fuel flow problems with 87 Johnson 35 hp.

kdc - Go to the red search and enter "test fuel pump." Plenty of info there. Also give some thought to rebuilding your carb.

 

[Yepblaze]

Re: Fuel flow problems with 87 Johnson 35 hp.

You test the fuel pump by giving the primer bulb a squeeze while it's starving for gas.<br /><br />If it picks up and goes, that COULD suggest the fuel pump but I'd look at the fuel connector, for an air leak first, followed by a look at the filter if so equuiped.<br /><br />If no increase in performance is seen suspect debris in jets, adjustment needed, or ignition maladay.

 

[alcan]

Re: Fuel flow problems with 87 Johnson 35 hp.

Hi Kdc<br /> There you are. I tried to respond to you earlier but something happened to the post. I beleive your model uses a manual priming pump. On the knob is an o-ring, this o-ring needs to be in good shape. Also when done priming be sure that the knob is pushed back in all the way. Go ahead and check the rest of the priming system for air leaks. Fuel pump overhaul kits are available for this model. Try to prove it has failed before you repair or replace. I don't think it's the fuel pump. If the primer circut checks out, then try to adjust the low speed needle on the carb. If you can't get the motor to respond (good or bad)then clean carb, paying close atten to the low speed circut.