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96 90hp 60 degree fuel issues

Run engine disconnect fuel line.---------Continue to run engine.------------Pump should then start to click rapidly when it runs out of fuel.
 
Whenever you even suspect that you might not be oiling, it a good practice to go ahead and mix the fuel to a 50:1 ratio. Then go thru the oil usage testing, and once satisfied you are using the right amount of oil, go back to straight gas.
 
Got the email notification from racerone about trying lid for vapor seperator. Did'nt show up here for some reason. Put a straightedge on it and it looks good. Put on new gasket. Am I missing something I can't see with straightedge?
 
Back in the water today. Had the pressure gauge on this time .5000rpm for maybe 2miles. Pressure from 2 to 7 pounds. Don't miss a beat. In the river so have to stop and turn around and while idling for a couple minutes pressure goes down and dies. After pumping bulb it's hard to start, had'nt done that before but after it cranks away we go with same result. Dammmnnnit!!!!!
 
daselbee said:
Whenever you even suspect that you might not be oiling, it a good practice to go ahead and mix the fuel to a 50:1 ratio. Then go thru the oil usage testing, and once satisfied you are using the right amount of oil, go back to straight gas.
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Put clear hose full of oil on again and it went down at a pretty good pace. Mixed a couple of gallons any way and smoked pretty much at idle. That part seems good.
 
Just put on the non vro pump. I unpluged the 4 wire connector from the pump and the 2 wire plug next to the trim switch on the motor. The 2 wire goes to the oil tank so I assume that is only the oil level alarm. Am I good to go? Have not cranked it yet (cold today) but when I turn on the switch the dash gauge turns on all the lights and then turns them off 1 at a time, just like before. Just want to make sure the check engine and overheat warning are still operational.
 
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Bundled up and went to the river. Had to see how it ran. The good part was it ran and idled and did fine except on sustained runs at wot. It did'nt fall on it's face like before but I could tell it was starving a bit after about 20 or 30 seconds. And no wonder according to the pressure gauge, it went down to near nothing at high rpm. Only about 2psi at idle. The VRO gained pressure at high rpm, Ranging 2-7. WTF
 
Davem02 said:
I forgot to mention, that there are two small hoses that come off the back of that solenoid & a large O ring where the solenoid goes into the fuel rail. Its possible one of the small hoses is loose or the O ring just needs replacing. Maybe not the whole solenoid. Check the hoses on the back of the primer, & the O ring.
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Replaced the red valve on enricher. Cured the leak, the oring was letting it by. Found out the air valve lookin thing was for injecting fogging oil for long term storage.
 
Seems as though nobody has anything else to say but me so I'll wrap it up for anyone that's been following. I took the wire spring clamps off pulse line out of desperation and used worm drive clamps instead and went back to the river. Gained almost 1 psi at idle, north of 3, and at 3500 was getting about 2 3/4. When I went to 5000 it dropped to just a bit under 2psi but no symptoms of starvation. Don't seem like alot still but the flow is strong enough to supply carbs so I guess I'll call it cured. One more thing that seems weird. When I tilted motor up to load on trailer the pressure went up to 4psi. Up and down the pressure changed with the angle of the motor. DamnifIknow.....
 
ss396fish said:
Bundled up and went to the river. Had to see how it ran. The good part was it ran and idled and did fine except on sustained runs at wot. It did'nt fall on it's face like before but I could tell it was starving a bit after about 20 or 30 seconds. And no wonder according to the pressure gauge, it went down to near nothing at high rpm. Only about 2psi at idle. The VRO gained pressure at high rpm, Ranging 2-7. WTF
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Well I will chime back in....OK so you have a new non-vro pump on it, and are mixing your gas.
So, at this point, you are saying it seems starved for gas at WOT, but doesn't fall flat like it used to do.

So, then, what happens when you pump the primer bulb at WOT when it seems to be starving a bit? Pumping the primer bulb forces fuel to the carbs thru the fuel pump, and basically acts as a manual fuel pump. If it picks up, runs right, then there is no doubt that there is a pulse strength issue, because you have a new pump on it.

I suspected a low pulse vac/pressure earlier in this thread, but I have not measured exactly what it should be...I have no VRO loopers to try it on either.

Low pulse vac/pressure is caused by a leaky crankcase sealing area. Either the crankcase joint, the crankshaft sealing rings, the lower crankcase to crankshaft seal, the piston skirt, or a leaky reed. This pump is driven off the cyl#4 crankcase, Right?
Of all those, the reed is the easiest to look at, but it is still a hard job.

I wish someone with a running VRO engine would volunteer to put a vac/pressure gauge on the FP pulse line of their motor to measure actuals...the swing back and forth, so we could at least try to compare.
 
Seems to be ok now. I tryed to put the new pulse hose that came with the pump on and without making it way too long it would'nt make the bend without kinking. So I reinstalled the original formed hose with better clamps and I believe I'm good to go. Think the non vro pump is a more constant pressure setup and although it don't get up to 7psi like the vro, it don't have to, and 2 or 3 lbs is enough to keep gas in the carbs. Very clean engine and would think any crankcase sealing issues would be leaving a mess. And somebody said a reed would show up spitting out the carb. Compression good. I admit I don't know as much as you guys but it's running really good and smooth. Would be interested to know if my fuel pressure numbers are consistant with other engines with this setup.
 
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