HELP! 1981 Honda prelude non-starting issue!


#1

Guys, I’m a pretty decent mechanic but I’ve got an '81 Honda Prelude with 1.8 liter four cylinder that has a gas-fouling/non-starting issue. The car has 98k original but sat for the last five years.

I got it started by installing new plugs, plug wires, distributor cap, rotor, igniter and coil. It ran great for five minutes. I killed it and restarted it several times but when it died on it’s own I found that the two spark plugs on the passenger side of the block fouled. I’ve replaced the plugs twice more since and gotten the car to just barely run but only for a few seconds before the same two plugs (side by side BTW) foul again.

It spins over great and has great spark but will not fire because of those same two plugs gas fouling out! HELP!!!


#2

If the vehicle sat for five years, you can pretty much figure the carburetor requires rebuilding from the bad gas.

The carburetor in your vehicle is a Keihin 3 bbl.

This carburetor is a very sophisticated in that, the primary and secondary venturi’s deliver a lean air/'fuel mixture to the combustion chambers. Simultaneously, the third venturi which is a completely separate fuel metering circuit delivers a small (in volume) but a very rich air/fuel mixture to the pre-combustion chamber.

RockAuto sells a rebuild kit for this carburetor. But not a remanufactured carburetor.

https://www.rockauto.com/en/moreinfo.php?pk=987327&cc=1169580&jsn=345

If you’ve never rebuilt a carburetor before, I don’t suggest that you learn how with this one.

Tester


#3

Are you using gas that was sitting with the car, or fresh gas? Could just be old gasoline.


#4

I don’t see how the carb or bad gas would foul only two of the plugs.


#5

Are you saying they’re just wet with gas, or are they black?

If just wet, then they aren’t firing.


#6

Guys, thanks. I grounded each plug while the motor was being cranked and each sparked. When I (briefly) got it running it ran like a new vehicle!


#7

Old gas or new gas?


#8

The first thing I would do is check the compression.