I have a 40 mercury with a flathead v8. I'm pretty familiar with cars and this engine but have issues getting it started. My question is how would you know if it's being flooded vs starving for fuel? I never know if it's not started because its flooding or if I need to pump it several times while trying to start it. It has an electric fuel pump and it does start sometimes easily other times I just give up.
The one thing I have found that flatheads do really well is start. A small bit of choke, one pump on the accelerator, touch the start button and it fires right up. I could always smell if my engine was flooded. Make sure you pump is set to around 2psi - 2.5psi. What intake and carb do you have? What ignition system? Just because it has trouble starting, don't assume it has to be a carb problem. Chappy
That car just arrived so I have just started to dive into it and noticed it has a Holley electric fuel pump and no regulator so I'm assuming it's probably somewhere between 4 and 7 psi which may be part of the issue. I think the carb is a stromberg 97 but I'll have to check tomorrow. I have a regular 1940 6v system with original ignition, distributor etc. I appreciate your response!
Pull a few spark plugs. If it's flooded they'll be wet with gas. With the engine off, lean over the carburetor and actuate the throttle. If you don't see gas squirting down the throat into the intake that might indicate lack of gas. While you're at it, check for spark as Chappy444 is suggesting. Let us know what happens.
A Stromberg needs a regulator to hold it down to 2 lbs. Get one of these Holleys and a gauge that reads down into the two lb range to make sure what you are adjusting to. https://www.summitracing.com/parts/hly-12-804 https://www.jalopyjournal.com/forum/threads/exclusive-1-5-psi-fuel-pressure-gauge.1146708/
Update**** I put in a fuel regulator and put it to 3 lbs. It always is easily to get it fired up when cold but after I drove it around the block and got it heated up then I cant get it to fire back on. An old flathead guy around here said maybe try a new coil. Battery could be draining from initial start and making the voltage and spark weaker after it heats the coil up? I always have the battery on a charger so it's a full battery when I attempt to get it started.
I had a 53 Ranch Wagon that would start cold every time , but not when it was hot. Since it was my daily I needed it to be dependable. I switched to a 6volt alternator and my hot start problems were eliminated. I thought it was vapor lock or fuel related , but when I would jump it with 12 volts it always cranked. So that's when I went with the alternator.
I had hard starting problem with 46-48 Flathead in 34 Ford truck. I did not know the age of the spark plugs. Got some new ones and it fixed the problem. Sent from my iPad using The H.A.M.B. mobile app
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