OHV16 replacement carb

blues124

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Hello
I have a Tecumseh OHV16 204211B. It was left out for several years and I need to replace the carb. The carb on the mower is a Walbro LMK41, Tecumseh P/N TEC-640000. See picture below.
In shopping around, I have been told by vendors that 640330A is the replacement carb, however that model has a fuel solenoid that mine does not. See a pic of 640330A here.
If I buy the replacement, how do I power the solenoid? There is no electric connector on the harness that could be used. I dont mind splicing wires, but dont know what to connect where.
Any advice?????
2014-10-29 21.56.59.jpg2014-10-29 21.56.37.jpg2014-10-29 21.56.15.jpg

BTW, thanks to all of you who do come here and answer everyone's questions. I greatly appreciate it.

-Steve
 
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Rivets

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In researching your engine I come up with a replacement carb of part number 640000. Don't know if this help you or confuses the problem more.
 

blues124

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Yes, thank you. The Tecumseh part number is TEC640000 (not TEK as I originally wrote) or just 640000. But I cannot find that carb available anywhere. The one place I did find it wanted over $100. I would settle for aftermarket, but couldnt find that either.

I did find one vendor on E-Bay who had the new part number and the photo shows a carb without a fuel solenoid (web link). ALL the other vendors show the same part number with the solenoid, so I've written the vendor to confirm. Perhaps that's the one I'm supposed to use?

Thank you.
 

reynoldston

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but dont know what to connect where.

Seeing the wiring harness is a lot different in different brands, models, and years it would help to know what this engine is in?? I would say wire it to the ignition switch. You might need a relay in doing this? If you just want to make the wiring very simple just wire the carb solenoid to a toggle switch. You will just have to remember to turn it off every time you are finish mowing or you will run the battery down.
 

blues124

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Re: OHV16 replacement carb - what to do with fuel solenoid?

Good points. Attached is the wiring diagram and parts list for the original mower and carb.
Wiring a toggle between the carb and the battery would be easy enough, and I could mount it next to the key, so I'd be unlikely to forget. I could even use an illuminated switch. A relay is easy too.
I guess it would be helpful if I could see the wiring of a mower with the new carb to be sure that it only needs +12 VDC and that it's controlled or timed in some manner.
wiring parts.jpgwiring.jpg
Thanks.
 
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reynoldston

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Looking at the wire diagram and key switch the only way I can see is. Looks like the white wire go's to the lights and the lights come on with the key switch. You could use that circuit to operate the solenoid but the mower would only run with the lights on and the mower would turn off in the run position. Another idea is a different style key switch.
 

blues124

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What would happen if I didn't wire it in at all? Would the solenoid prevent fuel from entering the carb?
I know the solenoid is supposed to prevent backfires, but I wonder how it can do that since the carb bowl holds enough fuel to running for several seconds after the key is turned off.
 

Rivets

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If you don't wire it in, the engine will get NO fuel. The solenoid stops the fuel from entering the carb throat, which means no fuel to the engine. Both the 640330A and 640000 carbs are readily available. The 640330A runs roughly $75.00 and the 640000 runs roughly $100.00. $25.00 seems to me to be cheaper and less headaches in the long run. Just my opinion.
 

reynoldston

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If you don't want to wire the solenoid, just a guess here, remove the solenoid and cut the plunger off?? It just has to hold the bowl on and not leak.
 
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