1997 Johnson 60 w VRO

[Dukemeister]

Hi folks,

Saga continues trying to get this old motor to run. Had the stator and power pack replaced, cleaned the carbs and it runs. It idles a bit rough but starts quickly and runs, but at idle on the muffs it will stall after about 5 min, seems it runs out of gas. If I pump the fuel line bulb it will catch and keep running and I can watch it and when it starts to slow down, pumping the gas bulb gets it going good again. I think this means fuel pump is bad... correct?

Also, the VRO seems to be mixing and delivering OK, because blue fuel is in the carbs. But, sometimes just before it stalls (if I don't squeeze the bulb) the VRO alarm will sound. The alarm stops if I squeeze the fuel bulb and the engine idles on merrily. Is this a "normal" condition with a bad fuel side of the VRO pump? Reason I'm asking is because a rebuild kit is only $150 for the fuel side but a new pump is like $500.


Thanks, Duke

 

[racerone]

I would start with a compression test on that motor.------Many VRO pumps are replaced as a guess for no reason.---Take the VRO pump apart for inspection before spending a penny !!

 

[boobie]

Try to rebuild the fuel side of the pump and the if it runs go to 50:1 fuel mix. JMO.

 

[Dukemeister]

Compression is good on all 3: 120,115,122psi. I believe the VRO pump works of the lower cylinder - so probably not compression related.
VRO Pump is now in the garage waiting daylight before opening it up... What to look for? Cracks, tears? General hardness of the diaphragm?
If nothing obviously torn.... what to do next.... just buy kit and hope for the best?

 

[WernerF]

I would guess that you will find a leakage/crack/pinhole in the fuel piston. A leakage in the diaphragm would flood the bottom cylinder when you pump the primer bulb.
There is no clue that the oil part of the VRO pump is bad. A VRO alarm just before the engine starves for fuel is "normal", since the oil sensor senses the pressure pulses in the mixing chamber caused by the oil being injected.

 

[Dukemeister]

As feared, nothing visibly worn, torn, cracked etc with the internals. In fact it looks and feels "new". Could it get stuck from sitting for a year?
I'm loathe to buy a kit to fix nothing. Next I will clean it, then reassemble it and put it back on to see if it miraculously starts working.

 

[racerone]

The pump is driven by a + pressure pulse and a slight - pressure pulse from the crankcase.----Ckeck and make sure that fitting screwed into the crankcase is clear.

 

[Dukemeister]

Cleaned and reassembled, installed - slightly better but still running dry so not pumping. I put my finger over the open end of pulse hose and turned the flywheel by hand, I could feel the pulses. One thing I noticed was before disassembly no matter how much I squuezed the fuel bulb it would never get hard. After reassembly, it does get hard with the engine off, but not while running. Does this mean anything for a diagnosis? Very puzzled at present. Fortunately my wife has me romodelling the bathroom at the same time, so i have switch projects while I ponder my fuel pump issue.

Is there any connection between the VRO and the primer side? When I push the key in I hear a click in the primer solenoid, but no increase in rpm and it doesn't help with the starvation problem. Only squeezing the fuel bulb will keep it going.

 

[boobie]

If your VRO isn't working the primer won't either when running.

 

[SparkieBoat]

rebuild/replace your VRO pump.

 

[sutor623]

I just rebuilt the fuel side of my VRO. I did it for peace of mind. Basically I have a good air pulse and fuel pulse diaphram that were removed from the vro. If I had waited until I separated the housings I wouldnt have bought the rebuild kit because it didnt need it. Anyways PM me if you want to try these diaphrams out. Im sure we can work something out.

 

[Dukemeister]

I'm now looking for an air leak between the quick connect on the motor and the carbs.
Pulled the carbs and gave them a good cleaning, nothing looked out of whack, floats good, level good, needles good, etc.
I have tightened all the gas line connections I can, but some have the plastic zip-tie factory originals that can't be tightened.
I now notice the gas bulb goes hard when I squeeze it to prime engine off, I can see fuel fills the inline in engine filter, but when I stop squeezing I can see the fuel level in the filter drain down... does this indicate air leak... if so where to look?

 

[SparkieBoat]

did you test your fuel pump?

 

[Dukemeister]

To test the pump would I just attach a clear line to the output and look for flow? I can at least do that.
I sat the fuel tank on the gunnel so the bottom of the tank was about 12" above the quick connect on the motor.... runs beautifully with the tank elevated.
I'm 95% convinced it's the pump now.

 

[SparkieBoat]

test fuel pump by disconnecting the fuel line from the pump to the carbs, prime bulb till fuel comes out. turn engine over and fuel should shoot out in fairly strong spurts, pull your kill switch so that you get no spark to the plugs.

 

[Dukemeister]

To close the loop on this tread, I installed a new VRO pump along with a new pulse limiter valve that came with it. Problem solved, runs and idles like it should now.

 

[SparkieBoat]

great. glad you were able to fix it.