87 EZGO Starts but no Power

[volvorcr]

New member here needs some help. I have an 87 EZGO 2 cycle gas three wheeler that I have used at the race track for about 15 yrs. This spring it wouldn't start after sitting for about 6 months (no spark). Got that fixed with new plug, plug wire, coil, and ignitor. Now it starts but it has almost no power. No gas in the fuel filter. Replaced the filter, lines, and fuel pump - no improvement and still no fuel in the filter. Pump just doesn't feel like it's working. Reasonable compression (125 psi). Any suggestions? Could the fuel pump problem really be no vacuum in the bottom end? Reed valve issue? Suggestions?

[cart around]

Remove the fuel pump, and put your finger over the hole while you crank it over. You should be able to feel the pulses that drive the fuel pump.

If not, you can use this manual for changing the crankshaft seals.

[volvorcr]

Thanks cart around. I tired that and I'm getting a pretty strong signal at the hole. I feels more like blowing than vacuum. I put a vacuum/pressure gauge on it and it's fluctuating around 0-15" vacuum so that seems to confirm a strong signal.

[volvorcr]

Update. Since I have a strong crankcase signal, I put the new pump back on. No pressure/vacuum at either inlet or outlet. Put the old pump back on, nothing connected, and i get a nice 3" vacuum at the inlet and similar pressure at the outlet. When I connect the supply hose to the inlet, I get a good stream coming out of the outlet. But when I reconnect the supply and drive it - same problem. When I leave the output connected to the carb and pull the supply line, I no longer see any vacuum on the inlet. That seems to say that my carb is somehow clogged?

[cart around]

Yes, give the carb a good cleaning. There is a vent line on the carburetor that just dangles. Maybe it got a mud bug in it. Another option is the float valve stuck closed.

[volvorcr]

OK. disassembled the carb. It was very clean, as it should be since it's only a couple of years old. Found the jet with the tube (emulsion tube?) loose and backed off about a turn. Fixed that. The float seemed way off so I adjusted that per the instructions in the manual. Put it all back together and the problem is still there. Both new and old fuel pumps produce 1-2" vacuum on the inlet and seem to pump gas when the carb is disconnected but the cart is still very slow. I did notice that it seemed to be more like normal power when running in reverse! Any other thoughts on what I might try next?

[Spicyunicorn]

Compression check may be in order if that checks out crank seals are likely bad

[volvorcr]

Spicyunicorn, did compression test first. 125 psi. Also, good pressure signal at the hole where the fuel pump sits so I assume the seals are ok.

[Spicyunicorn]

Oop sorry missed the compression part in your first post... On the old two strokes when the run better in reverse it was always one of two things rings were getting bad or bad seals it maybe worth looking into you know what they say about assuming

[volvorcr]

No problem spicyunicorn. Wouldn't the good compression and strong crankcase pressure signal indicate that it's not rings or seals? I'm now convinced that I don't have a fuel problem. Good crankcase pressure signal. New pump is working. All new lines and filter. Carb is clean and float adjusted. Float bowl is full when I take it apart (as I have now done many times!). 125 psi compression. It will start and seems to run as normal in reverse but fwd is down on power. Doesn't feel like anything in the drivetrain is different fwd and reverse, at least by just turning the clutch by hand. I'm now totally out of ideas.