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D7 3T pony motor not starting

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11 months 1 day ago #248561 by V14
Replied by V14 on topic D7 3T pony motor not starting
Carb rebuilt but still doesn't want to run without choke, only thing left could be the float is bad and I missed cracking. Still running much easier now since there was still some blockage in the passage I was able to get with those tip cleaners.

Any of you know what the difference between oil filter element 4a332 and 4w4840 would be? Was looking to get new oil and filters and the manual shows I need 4a332 but I opened up the housing and the previous owner was running 4w4840 filters. I'd generally just buy whatever was already in there but was curious because they do not show up as compatible in my digging.

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11 months 1 day ago #248562 by ctsnowfighter
Choke required - means the fuel mixture is too lean -- engine is starving for fuel
A cracked float would generally overfill the bowl, creating a high level of fuel and too rich. The float would not "float" and properly shut off the needle/seat.

Check you float level, check to ensure you do indeed have full flow to the carburetor, needle and seat are working correctly.
How did you set and check the float level? Low level in the carburetor will result in LEAN fuel mixture/delivery.

Every symptom you describe continues to point at fuel delivery/lean mixture.
Those can be caused by everything from improper venting of tank, dirt/debris in system, problem in valves, sediment bowl, lines, etc.
Then you also have to elimniate any issues of vacaum leaks between the carburetor and engine.

You do not mention anything about backfire or shooting back through the carburetor - those symptoms could be indicating intake valve problems.
CTS
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11 months 1 day ago #248564 by V14
Replied by V14 on topic D7 3T pony motor not starting
I forgot that hole in the header could be still causing too much air, I'll have to try and plug that and check again. If that doesn't fix it then I probably have the float too high, not sure why I thought cracked since that would drop it. I'm not getting any backfiring and gas still coming through clean. I'll give the stick method a shot shortly and if not fixed lower my float.
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11 months 1 day ago #248566 by V14
Replied by V14 on topic D7 3T pony motor not starting
I had it set to the 2 1/16" before tried it with 1 9/16" as the rebuild kit states. Seemed to be slightly better but I still had to feather the choke plate closed and open to keep it going good. Stuck a stick in the exhaust hole and didn't make any difference. Tried covering it with my finger (welding glove on) no change either. 
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11 months 1 day ago #248567 by V14
Replied by V14 on topic D7 3T pony motor not starting
I should also note that the air cleaner has been off during these tests just in case that may affect my results.
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11 months 1 day ago #248569 by V14
Replied by V14 on topic D7 3T pony motor not starting
Looks like not having the air cleaner on will make me run lean so I may actually be good once it's put back. Once I go pick up 10 gallons of oil I'll put some in the cleaner and see if that solves the issue, I'm fairly optimistic it will.

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11 months 1 day ago #248571 by ctsnowfighter
Air Cleaner On or OFF does not solve the issue of running lean. The air cleaner may help restrict the flow but it does not control the fuel/air mixture per say.
Carburetor has no feelings, no knowledge wheather the air cleaner is on or off. Many engines were produced without any type of aircleaner and ran just fine.
(as example Model T Fords - well over 15 million of them long before production ceased)
You have a fuel/air mix problem. find the cause and you can cure.

Your settings are very far apart, without knowing the individual specs, I am incline to believe you are way too high and way too low.
Needs to be JUST RIGHT

Where are you located?
You might seek the help and advice of local ACMOC or other "old iron" addicts. One cylinder engine enthusiasts, etc. They all deal with like issues.

These situations can be very frustrating and often the problem is very simple but easily overlooked, especially when one has been wrestling with it multiple times in rapid succession. There will be a "light bulb" moment and then the "why didn't I see that?"
CTS
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11 months 1 day ago #248572 by V14
Replied by V14 on topic D7 3T pony motor not starting
I'm in the western WA region. Reason I'm thinking it could be air cleaner is that I went from (after having the float higher) needing full choke to run period to now needing to feather it between open and closed to run nicely. Maybe I'm wrong either way I can get it running that's a positive.

So you are thinking my float should be somewhere between what the rebuild kit said for the different models or am I'm misreading?
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11 months 1 day ago #248574 by V14
Replied by V14 on topic D7 3T pony motor not starting
Well I went and tried with the air cleaner on just to rule it out and can't even get it started at all with it on. Take it off starts up just fine then have to do the choke stuff again. 
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11 months 1 day ago #248583 by trainzkid88
might be worth getting it sonic bathed. you can pick em up fairly cheap online. a tip is to put the item in a plastic container and only fill it with solvent filling the main tub with just water. saves money and time cleaning the unit its also safer.

most small engine shops have sonic cleaners and will do it for a small fee.
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