Sachs flooding problem

[Mpolly500]

I have a single cylinder sachs motor in my Amphicat. I just rebuilt the carb. It will run great when you first start. I drove it around a while made a couple carb adjustments to the high because it wouldn't open up. I let it idle a few minutes the. Drove it more. The. It died an the motor was so flooded with gas that I had to pull the carb an pull it a few times to get the gas out. I let it sit a while an out the carb on. It still won't start this is the second time it's done this. Any ideas?

[Mpolly500]

Ok so I went over everything again still floods very easy. My question is this, my gas tank is in the front under the dash when I turn the gas on a stream will come out of the other end. I have a diaphragm carb could this extra pressure of gas be too much for the carb to handle?

[LarryW]

Is there a return line? Maybe its plugged? I think the extra pressure would be fine. I dont know a lot about the 2 strokes or I would help more. Sounds like your close though!

[Mpolly500]

Yeah there is a return line. I already checked that though an blew it out with air. It's all clear. On the original set up the gas line goes up to the dash to the shut off then down. Idk if that's a problem or not. I broke that shut off an just put a regular shut off under the tank

[ArgoDude2350]

Is it gravity feed or does it have a pulse tube? What kind of carb? Your problem may be the reeds in the intake, if it has em. Make sure they aren't bent and that your float isn't sticking. You may also want it see how far the float opens. I had this problem with my carb.

[Mpolly500]

Yeah I seen your post I Think I relied to it first. No it's not gravity feed or not supposed to be there is a lot of gas flow. It's a tillotson HR carb with a pulse hose hook up. I just rebuilt the carb an even tried a different HR carb. Same problem. No reed valves either. Everytime i think it's fixed it something else. I'm running out of ideas

[ArgoDude2350]

Check your intake manifold gaskets, to make sure they aren't leaking. Also, check where the carb attaches to the manifold, to make sure they aren't leaking. Try using some gasket sealer...the tacky stuff. Also, make sure that you didn't adjust the gas flow too far. This could also be the problem. Sometimes if the inlet needle will get dirty, or opened too far and severely flood the engine. Be careful not to bend a connecting rod from engine locking. Hope this helps!

[Mpolly500]

I just out all new gaskets an checked everything. I even pull the motor again today an drained about a pop bottle worth of gas out of it. I blew it all out an cleaned everything again an it still won't start last time i let it sit for about 4 days and it started an ran for about 10 min. Then it died an still wont start

[ArgoDude2350]

You may want to run a compression test on it. Did you replace the crank seals? This may make a difference. Did you make note of the carb needle positions before you began adjusting? Maybe it is just getting too much through. Did you check the float?
Is the gas going straight through the motor; as in coming out the exhaust pipe? If it is, you may have a compression problem. I have a 400cc Kohler doing the same thing with a tillotson carb. I think it is my rings or crank seals. It could be something simpler for you. Next time you get it to start, let it run. If it shuts off, pull the spark plug, wipe off any gas, and crank over the motor. If there is no spark, this means that you are not burning the right amount of gas and has a bad condenser. Sorry to bombard you with so much stuff.....so many options and I know how frustrating it is. Let me know......

[Mpolly500]

Already did a compression test right at 119 psi. I counted the turns in the new screws as I turned them in an set the new ones a little tighter like a 1/4 of a turn. There is no float but the needle thing an yeah I believe it is set right I really don't think it's the crank seals I've had that problem on other engines an this isn't showing those signs. I'm leaning more to the fact about the gas tank an all the natural pressure it's creating. I'll have to leave it sit a couple days I guess an when it starts I will check the crank seals with starting fluid. This machine ran great before the diaphragm ripped in the carb.

[Mpolly500]

If I pull the plug an turn the engine over a couple times then put the plug back in a try to start it. It won't start so I pull the plug an turn the motor over some smoke will come out but the engine never fires

[ArgoDude2350]

The only other things I can think of would be spark or your carb. Is the diaphragm seated right? I think the diaphragm part number is L404. You know, I remember hooking a primer bulb up to the main line on my HR. I'll bet that the pressure from your fuel tank is holding he diaphragm and the needle open, allowing free fuel into the motor, no matter how you adjust the main fuel flow needle. Maybe try another gas tank, like an outboard tank or something hooked up outside the machine with no gravity pressure. I have an Argo where the tank is under the seat, and I don't have a problem getting the gas to the carb. You may find that it really is that pressure. Sounds like an impractical design on Amphicat's part. Is it the original engine and carb?

[Mpolly500]

Yeah its the original motor an tank. Only difference is the fuel shut off not being in the dash which would make a a difference because instead of the line coming out of the tank an going up an then down. It comes down to the shut off an then to the tank.

[ArgoDude2350]

I'll bet that's your problem. Too much pressure to the diaphragm, leaving the float needle open. Maybe try routing the line differently, or acquiring a shutoff, or a quick disconnect, something that could change the route of that fuel. Hope it works!

[Mpolly500]

Well I got it started last night. It was running bad dint want to open up I tried 3 new plugs be fore it ran good. I think I just got a batch of bad plugs. I do have to shut the gas off an let the engine run out of fuel if the gas will pump into the motor. I reran the lines an it helps some. Idk what else it could be.