Inherited a nice 85 Spree, but can't get it to start

[adubb]

I recently inherited a 1985 Spree that's been in our family since it was purchased new (I have all the paperwork). It's been garaged the whole time and was running as recently as a few years ago. I'm not much of a mechanic, but here's what I've tried so far.

1. new battery, spark plug, air filter
- electric starter turns it over fine, but it won't start

2. took off the carb, disassembled, soaked and blew compressed air through all openings, re-assembled (it looked pretty clean)

3. suspected carb wasn't getting gas. eventually I sucked on the vacuum tube and could hear what sounded like a little click in the petcock and the sound of fuel flowing. I then disconnected the fuel feed to the carb and was getting lots of fuel .. more than a line full. Subsequent to that, it just seems wonky. I suspect the petcock valve is shot. Ordered a new on from Amazon only to find out they must have sent the one for > 85 because the threads don't match! Ordered another one from eBay this time.

4. A short burst of starter fluid sprayed into the air intake definitely fires it for a few seconds! (was this a bad idea?)

5. Experiments with just filling the fuel line haven't produced any success. If I open the drain on the carb, it has fuel. Pretty convinced the float mechanism is working.

So .. I'm sort of scratching my head at this point. I think the fuel valve is bad, but that shouldn't stop if from firing a little with the line manually filled. Could I have two problems? Seems unlikely.

[vintagegarage]

Leave the air filter in place. Fill a pump type oil can with gasoline and a little bit of 2-stroke oil. Then unscrew the top of the carb (the round piece that the throttle cable goes through, and lift the top up just enough so you can squirt a couple of good squirts from your oil can directly into the throttle slide, but not enough to remove the slide. Then screw the top back on. Then hit the starter button. If the engine runs for about 3 seconds and dies, then either you still have no gasoline in the carb float bowl, or your idle circuit is still blocked. Try the test again, but this time, once it fires, open the throttle quite a bit and see if the engine will run on the main jet. After the test is complete, open the drain on the carb and see how much gasoline runs out... then report back here on what you find.

Also take a minute and update your profile with your location. You may find someone close to you who can help.

[adubb]

Tests complete!

I mixed 4 ox of gas with about 2-3 droppers full of 2 stroke oil. Followed your procedure about 3-4 times and it definitely fired up and ran for 4-5 seconds. I tired to be aggressive with the throttle on the last 2, but it didn't keep running more than a few seconds. When I opened the drain, I didn't see anything drip out at all (and I have seen this work in the past).

Thanks so much for this little test. It was exciting to hear and smell it run if only for a few seconds. Next steps?

I did update my profile. I'm in the San Francisco bay area, near Stanford U.

[vintagegarage]

When nothing came out when you drained the float bowl, that is pretty good proof that there is no fuel in the float bowl. Either your fuel line is blocked somewhere, or the vacuum petcock on the bottom of the gas tank is not working or there is no vacuum in the line to the petcock that opens it. Also make sure that you haven't got the lines to the petcock reversed. You should be able to put a piece of hose on the vacuum connection on the petcock, and then suck on that hose, and fuel should flow out of the other connection on the petcock.

In my mind, you have verified that your ignition system is working properly, and you have a fuel delivery problem. Once you solve that, you should be good to go..

[adubb]

Yes, seems to be. As I noted in my original post the petcock seems faulty. The suck on the vacuum hose thing seems to work the first time, but maybe worked too good as a lot of fuel flowed out. Now nothing comes out if I try the same thing. Maybe the diaphragm is dried up and rigid now?

I have this on order: Thread 14mm x 1mm Fuel Valve Petcock Switch For Honda Spree 50 NQ50 1984 1985

Thanks again for your help.

[motormike]

Let me stress the importance of "pilot jet flow"
and "bystarter operation". Both must be meticulously verified in order to
achieve good carburetor function and engine behavior...motor

[adubb]

Fuel value "petcock" is definitely bad. First ordered from Amazon was good quality, but wrong size (despite saying 1984-1985 in part name). Second ordered from eBay had the correct nut, but it did not turn freely on the valve and I snapped off one of the nozzles trying to wrench it on the the tank. Anybody have a tip on where to order a quality fuel valve petcock for a 1985?

[Meatball]

Its the threads on the fuel tank that are unique. I once destroyed a Spree tank by cross threading an Ebay petcock that “fits 84-87”. Ordered two others from different sellers just to have the same incorrect threads. Live and learn there.

Just get an in-line manual fuel valve and turn on/off the fuel flow manually every time you run it. Dont forget to block off the vacuum port since the vac hose will be removed.

[adubb]

Ok .. well I'm only out about 20 bucks but it's frustrating. I've got a new tygon gas line on with a poor man's valve (vice clamps). Where should I block the vacuum port? At the carb side (I guess it's not technically on the carb) or at the petcock?

[adubb]

I have a Tygon line on now for fuel, so I can see fuel in the line. When I pull of the fuel line, fuel flows freely from the tank, but when it's all connected I never really see fuel moving into the carb. I can turn it over with the starter and/or turn the experiment where I inject some fuel/oil into the throttle housing. When I do that latter experiment it fires for a few seconds, but I don't see any fuel moving, nor does there ever seem to be any when I open the drain.

What (other than gravity) allows the fuel to move. As I'm typing this, I realize it could be the float valve, but before I reassembled the two halves of the carb last time I did a test where I injected fuel while hold the float with my finger and then when I released it, the fuel did seem to spill out.

I'm scratching my head over here.