Starting issue...I'm puzzled

[OMCfan]

Greetings fellows,

I have been working on a QD-16 and after much fuss I cannot get the bloody thing to fire. I have replaced the entire ignition system, including wires plug boots and new plugs. I had a leaky pressure tank and so, I have rebuilt the tank and the leaks have been taken care of.

I also installed a new carb kit.

The problem is that I am not getting fuel from the carburetor to the combustion chamber. I have fuel to the carburetor. To test my theory, I did pull the plugs and sprayed fuel into the cylinders and then replaced the plugs and she fires on the first or second pull.

This engine was squeaky clean when I bought it so it's not like I had to evict insects and grime out of it. Needles are set at standard initial settings.

 

[boltonranger]

Describe the carb rebuild. Did you soak it and/or blow out all the passages? This is crucial.

 

[F_R]

OK, you say you have fuel TO the carburetor. Do you have fuel IN the carburetor? If you do, and the needles are set somewhere near normal, and the choke is closing, and the throttle butterfly is synced and the reeds are OK and the engine is viable it will get fuel to the cylinders. Check out the "ifs".

(By viable, I mean compression, crankcase sealing, and unrestricted exhaust)

 

[OMCfan]

Here is what my carb went through. I disassembled the carburetor, soaked the upper and lower halves in carb parts cleaner for 24 hours then cleaned them with carb, choke and throttle body cleaner, I blew out the passages with more carb, throttle body spray and then installed the new kit including needle packings. I also blew out the small hole under the aluminum cap on the top of the carb and sealed the new cap after installing it.

The motor had no oil leaks when I bought it, has at least if not better compression than my '56.The exhaust ports are clear. I got it to run for a few seconds several times after the carb kit and before I redid the fuel tank ( I had fuel going every where) and the exhaust was clearing out of the port.

When priming the motor with the button, I have fuel filling up the glass bowel on the carburetor, so I know fuel is getting that far.

The choke seems to be functioning fine.

Should I take the carb back off and recheck everything?

 

[OMCfan]

When I disconnected the tank hose, fuel ran out of the line coming from the float bowl so, fuel is at least getting that far. The choke seems to be functioning fine. One thing I did notice involves the function of the advancement for the throttle. With the shifter is in neutral and the throttle advanced to start (that's as far as it will go) I noticed that the rubber advancement roller on top of the carb. barely moves the butterfly shaft at all at this point. However, the thing would not start when the choke was pulled out. So I don't know if my finding is significant or not. The low speed needle is out 1.5 turns and the high speed needle is out 1 turn.

 

[bspeth]

I think you should make sure your float/needle are not stuck.

 

[OMCfan]

Took the carb off and opened it up. The clip that attaches to the needle and the float had come off....I have no idea how. So it may have been just a stuck needle. I will find out tomorrow.

 

[HighTrim]

Did you have it on correctly? Tight wrapped side around the head of the needle. Larger side over the float arm.

 

[OMCfan]

Yep, that's how I had it. I tightened the portion that goes around the needle and then put it back. So hopefully it stays.

 

[HighTrim]

I find the Sierra ones loose fitting. The OEM ones have a very tight fit, you almost have to "pop" it on, which is good.

 

[OMCfan]

That is what I put in was Sierra....OEM next time!

 

[oldboat1]

Might be missing the boss gasket for the nozzle, or the filter bowl gasket is not sealing. Also possible that the sintered filter is clogged -- might try it without the filter in place if you continue to have problems.

 

[OMCfan]

Thanks oldboat1,

I wondered about the filter and tried it without and it made no difference. I soaked the filter in carburetor, throttle body cleaner and reinstalled it. I do have a new boss gasket in place, as I know that is pretty critical. I am going to make sure the glass bowl is snugged down tight before giving it another try. I also ordered a new one just in case. I am going to put it back in the tank tomorrow and see if I have any luck. The skeeters are so bad , I can hardly stand to be out of the house.

 

[oldboat1]

sounds like you are closing in on it, anyway. Hey -- good luck with the skeeters. Two months worth of near drought here this summer -- bad for corn crop, but fewer skeeters....

 

[OMCfan]

Oldboat1

I got it to fire today and run for a little bit several times so I think I just need to adjust the needles so she'll stay running and then go from there. I played with it all I could stand and the skeeters drove me back into the house.....miserable! Hopefully she will come to life and be a great motor...I have high hopes anyway.