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TR2/3/3A TR3 Hard Starting

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SWFTR3

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!957 TR3, has been a good decent runner, but just very recently became very hard to start, almost overnight. When I can finally start it, can only keep running by continuously pumping the gas pedal. Shutting off, the plugs all look the same, very dry black soot.
Weak spark? Overnight dirty carbs? Can't figure out what happened overnight, and where to start.
Thanks for any thoughts and advice.
 
If you have an inline fuel filter, change it. Disconnect the fuel hose at the carbs and turn the engine over to look for adequate fuel flow. Use a can or jar at the open hose end for the gas that comes out. If the gas isn't there, clear the fuel lines. Blow a little compressed air thru the fuel line toward the tank from the supply line to the pump and from the carb supply line back to the pump outlet hose. This will dislodge any accumulated gunk. Having done these things, hook the fuel pump back up and check for output at the carb supply hose again Almost certainly not ignition related and almost certainly not the carbs themselves. Let us know what you find.

Hi from Everglades City,
Bob
 
Last edited:
bobhustead said:
If you have an inline fuel filter, change it. Disconnect the fuel hose at the carbs and turn the engine over to look for adequate fuel flow. Use a can or jar at the open hose end for the gas that comes out. If the gas isn't there, clear the fuel lines. Blow a little compressed air thru the fuel line toward the tank from the supply line to the pump and from the carb supply line back to the pump outlet hose. This will dislodge any accumulated gunk. Having done these things, hook the fuel pump back up and check for output at the carb supply hose again Almost certainly not ignition related and almost certainly not the carbs themselves. Let us know what you find.

Hi from Everglades City,
Bob
Click to expand...
Thanks for your advice, I will try it!
 
Sounds like the choke is stuck, or a jet not returning. Check to see if the choke return springs are in place then check to see if the jet returned flush to the bottom of the carb housing. If you can, take some pics with the choke out and the choke in, that would help. The picture needs to be with air cleaners off and close to the bottom of the carbs and get both carbs at the bottom at an angle. The black is carbon from running rich. SUs work by enriching the fuel mixture not by shutting off the air like most carbs. Plus make sure the pistons drop freely with the brass oil filler dampeners plugs removed.

steve
 
I would just give it the old "annual tune up". That includes setting the tappets, cleaning/gapping the plugs, checking compressions, checking the high tension wires, cleaning and setting the points, rotor and cap...and finish up with a cleanout of the float bowls and checking the fuel float level. Then clean out your fuel filter and set her idle mixture again... and I guarantee she'll go back to starting great.
 
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