Trouble starting

[bobcat1/178th]

Hey troops, my 66 151a1 has been having trouble getting started when cold.....the engine cranks away but takes as long as 10 seconds + before it fires up....that's with full choke on....Once it warms up there is no problem starting back up....

On side note in the heat of the summer it vapor locks after shutting off ....I expect that this could be in part because of modern fuel but is there a way to prevent this....

[rickf]

A couple things come to mind right off, float level and fuel filter, followed by fuel pump. Are you running the factory electric pump or an A2 mechanical pump? Next question is what carb and has it ever been rebuilt? And you say choke full on but have you physically looked at the choke to verify it is fully closed? Could need cable adjustment.

[bobcat1/178th]

I'll replace fuel filter . Could use it anyway I'm guessing.....I'm running the original style elec fuel pump...replaced with NOS probably 6 years ago.....choke cable good....door closes fully ......carb is original to engine and was rebuilt 6 years ago.....

[rickf]

Ok, Back to basics then. Timing, points and condenser if you have them, valve adjustment and spark plug condition. What gas are you running in it? Premium gas can cause this issue, especially in low compression engines where it is not needed nor recommended.

[Mark]

Try starting fluid, if it starts up immediately, obviously that tells you something, I guess 1 spray is the rule?

[Horst]

my experience is that even a little bit timing off will cause starting issues, despite the engine runs otherwise ok. Check the timing with a timing light.

[bobcat1/178th]

Ok. Thanks.....will check timing....I run Reg Unleaded .....electric ignition.... No points....

[rickf]

Ok, As long as the gas is fresh then that is not the issue. With the electric fuel pump as soon as you start cranking it should run the pump and even if the carb was dead empty it would fil in a couple seconds if the float settings are correct for height and drop. You can take the fuel line off at the carburetor and do a flow test to see how much volume is coming through. You can do this one of two ways, You can pull the plug off of the oil pressure safety switch and with a jumper wire jump the #77 and #77a wires. Then when you turn on the switch the fuel pump will run and you can check the flow. If you are not comfortable with that then you can just take the line off and crank the engine with the switch off, it should start pumping fuel instantly as long as it is cranking and stop when cranking stops. Either way you are looking for a good solid stream of gas, I did not mention that you need a can for this to go into but a can is needed.

[bobcat1/178th]

Ok...will do