Trying to find a rootcause for my engine that generally runs great, but when hot it starts to studder... and if i stop it, its difficult to start again. When hot it runs great in idle, but when its time to perform, like just starting in 1. Gear it studders.... when om at 3. Gear and my speed is ok i release the throttle and it runs great... with occational studders... The thing is that i thought it was waper lock, but i have just measured the carb temperature and fuel, and its 35 degrees.. i can easily hold my hand on it. The fuel line is 40c. The engine top is 80c.. all in degrees centigrade. I had the problem both with a newer holley carb, but also with my new correct stromberg 79. The ignition capasitor is new, and was 60 degrees, together with the ignition coil. Engine is stock 32, carb is jet as stock. Help? Sent from my SM-G850F using H.A.M.B. mobile app
Regardless of temperatures...be VERY suspicious of coil and capacitor/condenser. This is exactly how they act when in poor shape. Try replacing with others (there is a simple adapter, like Ford Germany used to use, to use a normal coil like VW on the '32 distributor), and a cpacitor from almost anything will serve for testing that. Also, when idling hot pull off a plug wire and hold it near head...with coil failing you will see a thin yellow spark. If coil good, spark will be fat and blue.
Thanks. How about bad fuel pump. Can that have same symptoms... or vaper lock at the pump maybe ? Sent from my SM-G850F using H.A.M.B. mobile app
The old trick was to cut a grapefruit in half and stick it on top of the pump when you got vapour lock! The new trick is an electric pump,either way you know what your battleing.
The condenser is new... nos that is... probably not as good as a new one. Sent from my SM-G850F using H.A.M.B. mobile app
I will look into a electric fuel pump to rule out that part... Sent from my SM-G850F using H.A.M.B. mobile app
How about the carburetor's condition? Is this a 1 bbl Ford carburetor? (You said '32) A good cleaning of the carburetor, and dead sure of needle and seat operation; Take the main jet and polish the bore with cotton twine. Examine it first, under a magnifying glass...it'll look like barnacles on the inside. I'd perform this task to give it the benefit of the doubt prior to buying/installing an electric pump... Only AFTER doing as Bruce suggested. The blue spark can be observed under a roof, i.e. in the garage.
"Like near your forehead, your ear, your nose, or what?" User option! A good spark is a multi-media event! If you hold wire near cylinder head, you can SEE it. If you hold it near your head, you can HEAR it. It will sound like "AAAaaayEEEEE!!! ##%#& the ^&%$@#$ #!#%$!!!"
A new part in the box, does not mean that it is good part. Have had many new electrical parts that not good. Follow what Bruce is telling you.
This is good info and should apply to about anything. LOL stick your finger in it then hold the other hand near anything grounded, I guess you could use your nose instead but when you are that close it is really had to tell what the spark is doing unless you are near sighted. By the way we used to put a close pin ( wooden) on the fuel line for vapor lock.
Heard about the cloth pin too, but doubt it would work. Ill take the fuel pump apart in a moment.. it seems dodgy... no real pressure on the lever no matter how much i pump. Seem to remember it used to suddenly feel resistance when carb was full... Sent from my SM-G850F using H.A.M.B. mobile app
By the way we used to put a close pin ( wooden) on the fuel line for vapor lock. I thought close pins were for nipples!! Oh Thit!! Wrong Forum!! Pete
I found that the outlet of the pump i could just as easily blow into as suck. So i found that the outlet valve thingy was not tight in the body, i gave it a shot at rivit punching it in place and that worked. Now it pumps much better.... but the problem is still there... when people say vaper lock, do they realise that the pump is closer to the engine than the carb... the pump was engine hot.. ill definatly do a setup with a electric pump when in setup.. but it had better acceleration responce... Sent from my SM-G850F using H.A.M.B. mobile app
Great fat snappy blue spark... but discovered a hissing sound when the engine died.. i took the top of the pump and saw boiling gas... thats my problem... Sent from my SM-G850F using H.A.M.B. mobile app
Boiling fuel in the fuel pump. Its not as bad in the video as when i initially removed the lid. Sent from my SM-G850F using H.A.M.B. mobile app
Have taken the pump and pump stand off, ill experiment with some heat isolating spacer both between pump stand and msnifold and between stand and pump. And have some cooling surface around it. Sent from my SM-G850F using H.A.M.B. mobile app
http://www.fordbarn.com/forum/showthread.php?t=136480&highlight=vapor+lock Real good information!! Pete
Thanks. Indeed good info. Somewhat the same take on the problem. But i want to try something slightly different.. ill be back with the results when i have the parts in house.. Sent from my SM-G850F using H.A.M.B. mobile app
Don't space it out too far or the push rod won't be able to actuate the lever arm on the pump. Might risk having it hammer away on the pump arm too if the clearance is opened up.
Correct. Looking into extending the rocker lever in the pump, and moving the pivot hole, then there should be lots of space for a spacer Sent from my SM-G850F using H.A.M.B. mobile app
I've been thinking on this in terms of the carburetor heat shield GM used on some performance applications long ago...thick gasket, then a plate of aluminum under the carb about the size and shape of the carburetor's shadow, thin gasket on top of that. Obviously anything like that here requires an extended push rod compensating for the thickness of the heat shielding. Also...for running, look into OJ's return style pressure regulator, a small valve the sets pressure to carb and returns bypassed fuel to tank. This keeps fuel in fuel pump continuously renewed by cooler fuel from tank. For starting...the inlet valve of pump needs to seal well and be able to pull a good vacuum and hold it for a while.
Have been thinking about that solution too, read it on the net, but im unable to read pressure between pump and carb.. but the carb do get fuel, so thinking its very close to null pressure, but as long as it works. I will insert a printed circuit board plate between pump and stand with the copper facing the pump, that way its isolated, and the surface desipates heat on the copper surface... worth a try. Sent from my SM-G850F using H.A.M.B. mobile app
Problem solved.... systematicaly changing or renovating each component. Time had come to the distributor and points. Having it in a fixture for checking the open and close times it was found that ignition positions were correct..however the dwell time was way off... setting up the dwell and it runs like new... and the coil is not getting nearly as hot as before. Before i could fry eggs on the coil.. now its normal... dwell time is definately something to take seriously... Hope it helps others. Best regards Kom mortensen Sent from my SM-G955F using The H.A.M.B. mobile app
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