1979 Trailfire won't run

[NDR]

So I got some great help from everyone for my Trailfire 340 and it's electrical issues. After I got the electrical issue sorted I took everyone's advice and replaced the crank seals as well as all of the other gaskets. Yesterday I got the motor re-installed and started it up. It seemed to run good and rev fine with no load on the motor (had the back end jacked up). We got a light snow last night so I went out to see if it would putter around the yard. It ran fine for a short while and then started to bog. If I worked the rpms up it would go full throttle and just scream but as soon as I let out of it, it bogged again and died. The only way to get it restarted was to hold the throttle wide open and pull it over several times it will start to sputter and eventually rev up. It idles fine but won't rev up much past idle. I put fresh fuel in the tank and also tried adjusting the needle and air screw. Currently my clip position is the second from the top. I thought I had it going good (puttered around the yard for probably 10min with no bogging and a couple full throttle pulls) and that is when I filled it up with a full tank of gas. It started perfect and idled great but as soon as I tried to drive away it started the same crap as before. To keep it running after it bogs I can flip the choke open for just a second while pulsing the throttle and then flip it back off as the rpms come back up. I don't really know what to try next. I have plenty of fuel and if I do not shut the gas off when parked the engine will flood. Any ideas will be greatly appreciated.

[harleysportster]

Sounds like you need a new needle/seat in carb.

[NDR]

As in the float needle?

[harleysportster]

Correct

[NDR]

How is that creating my problem? Won't that cause flooding? Is that what's causing the bog? Sorry, not trying to be an idiot my brain just isn't really working tonight...

[harleysportster]

If the engine is flooding, the float needle may not be closing completely.

[sledhead16]

It definitely like Pat said sounds like a fuel delivery issue. Did you check Vintagesnow.com for the correct eclip setting maybe 3rd position also correct pilot air screw setting. have you gone through the carb? Sounds like your needle and seat are not creating a tight closed seal. http://www.newbreedparts.com/newbreed/i ... uct_id=194

[NDR]

I've cleaned the carb several times with no luck. I tried some different clip positions also. When I get richer the throttle seems to hang. It about got away from me. I cracked the throttle just a bit not expecting much and it reved suddenly and didn't come down very fast when I let out. That was on the third clip position. Was it loading up or hanging up due to lean condition? I agree the float situation needs addressed but will that cause the issues I have while it's running? Also the air screw was in past stock to get it to idle. Looking back on these issues now I'm thinking it's still lean. Plugs didn't show that but I could not keep it running long enough for that to be a valid test.

[NDR]

One other thing I forgot to mention. I do not have hose clamps on my impulse line. I plan on getting some just didn't have anymore left when I put it. Could that be killing my fuel flow when I get the case pressure higher at higher rpms?

[JDT]

You may also want to check for free play in your choke cable.

Without proper free play the choke may not close and that can cause flooding issues.

[JDT]

If your slide is sticking in the carb look for a bent needle.

[NDR]

Today I did some more tinkering. I tried moving the clip around and it seemed to be the best on the 4th position. I set the air screw at 1 turn out and I thought it was running pretty decent. I drove it around the yard a bit and I actually thought that it was fixed but after probably 10min of riding around the yard it started to bog again. It was doing fine at half throttle but after it started to bog it really only wanted to idle or go wide open. I could get it to keep running by flipping the choke on and then quickly off and it would kinda come back. If I left the choke open it would just start to blubber and die. I got it back to the shop and tried some different air screw settings. further out seemed to make it worse and eventually I just turned it all the way in. It's very inconsistent and that's what confuses me. After running terrible for a while it will go for 5 min with out a bogging issue. I pulled the carb tonight and took it apart again. When I pulled it off the boot on the air box side was very wet with gas and the air box also was wet. Way to much fuel or other causes? The floats float and the float needle has no grooving in it nor does it stick in the seat. The top pin on the float needle (the little springy part) is some what worn. It has a slight bevel to one side, will that cause huge issues? When taking the choke off I do not think that it has much play if any at all. I will adjust that tomorrow also. Will the choke issue cause that much of a fuel over flow?

For reference:
Main Jet- 190
Pilot Jet 30

[JDT]

I do not have a manual in front of me but I think 1/8" of frree play is what you want on the choke cable.
Otherwise when the cable moves(flops) around while riding it opens and closes the choke plunger intermitantly.

[NDR]

I have a manual so I will check. Will the carb kit that sledhead16 posted work for this carb? it says some VM34 trailfire carbs used VM30 rebuild kits.

[JDT]

I Don't know what your carb looks like on the inside.