Engine loses power under a load

[BIG MIKE]

Took the tank out teasterday in a Large field she ran good untill I took her up a steep hill then back down. This hill was so steep that none of anyones cars here would make it. after getting back down to the bottom the Motor started sputting, and the motor would quit when trying to turn to lock her brakes from left to right. I would put the pedal to the floor and she would completely stall, even trying to run her thru the tall grass she would not accelerat. She starts up fine Idles Great dosent smoke , and was not that hot in the Rad. plugs were a light brown with good mixture could it be ?

Rust particles got past the filter into the carb?
Fuel pump rod no good?
carb fuel pump acc?
vapor lock?
maybe varnish in carb?
Vacum line? goes from top of manfold to Dist
Motor is a 36 Flathead

Basiclly it was hot and humid and everytime i try to accelerate she would lose power, any help would be great, Asdo I cooked like a Lobster Cheers BIG MIKE

[Scott H]

I'd give it a day to see how it acts after being cooled down. Sounds sort of loke vapor like, especially when you consider not just the weather conditions, but also you probably got it a bit hotter tackling that hill.

[Frank The Plumber]

If the hill was so steep that none of our cars would make it consider this, I had a 4x4 with very large mudders, she could go through anything, over anything up anything, but she had injection and that is why she could, your floats are gravity balanced and when you went up the hills you flooded and leaned and starved your carb and engine, just that momentary flooding is enough to fuel flood and foul your plugs and can foul your oil and wash your cylinder walls and trash your block. This is why I put fuel injection on my big 4x4, she fuel washed the cylinders and locked up. Check your oil, clean your plugs and stop climbing hills without the proper fuel setup.

[Mick/mo]

Yup, your right on. If it were in an airplane it wouldn't fly upside down very well.

[G.M.]

Sounds like you shook up the dirt in the gas tank and it is partialy closing the pick up tube in the tank. Once this starts it don't go away until you clean the tank. Blowing back through the gas line with the cap off usually clears it for a short time. I just cleaned my tank a few weeks ago and the problem is gone. G.M.

[BIG MIKE]

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thought that was the case GM , going to put and extra fuel filter in after I drain the tanks gas tanks then the lines and clean out the carb and mech Fuel pump , Cheers, Mike

[G.M.]

That won't fix the problem. It will keep the dirt out of the fuel system parts but still stop off the pick up tube. G.M.

[BIG MIKE]

It's eith the gas tank clogging up the fuel lines or it must be aswell the Points and or the dist parts as well I will be checking everythingxt event ain't until middle of Oct. Cheers Mike

[FlatheadTed]

Run the moter with one plug wire to a head bolt ,Rev it and see if the spark doesn't jump the 3/8 to 1/4 gap .If not then start looking at all the electrical s Points ,condenser swap out the coil ,Strip & Clean the carb with compressed air

[BIG MIKE]

Ted She Ran Great Just starting her up and a good idle , But as I tried to lock her up on either side to turn her the engine started to putter out, pedal all the way to the floor this was absouluty no power. this is something that I never had dealt with before. Big Mike is worried

[G.M.]

Run it off a gallon can of gas and see what happens, this will save a lot of fooling around. G.M.

[FlatheadTed]

When it runs bad switch of and lift the top of the carb and see if the fuel level has dropped ,this should show you that the pump or fuel line has a problem.try a wire direct to the coil ,if its the old stock one ,make it a quick test only ,this will show if its a voltage drop .Ted

[BIG MIKE]

Lads I Ran Motor today, took off oil bath breather tube Noticed snap poping noise coming from carb, carb needs to be cleaned?, also noticed bubble's in the glass bowl???? Fuel pump reg read 3.5 psi, Rod and Diaphrams looks to be stably good in pump, I ran motor about an Hr and still could not get the right mixture . Also took off a plug wire held it tro a stud it gave a good orange glowing spark, after that took out gas tank drained it out lots of guck on bottom , will be putting in a new fuel line filter this week. Also can I put in Premuim or high test gas in my motor? if I want to clean carb can i use a air compressor without takeing the carb apart? or can I dip it in paint thinner?, No oil in Gas , No oil in Water No gas in Oil. all is good on these fronts , any adivise agasin would be great , Thanks Mike

[G.M.]

What kind of gunk? If it's varnish get a gallon of denatured alchol at the hardware store and soak the inside for a day or more. Set the tank on saw horses in the shade and roll it around once in a while. The new gas will melt the old varnish and bring it up in the carb and gum up the needle valve and other parts. You could dunk the carb in the alchol for 4 or 5 minutes before useing it in the tank Blow the carb out and put some MMO in it. See what the tanks looks like, it my need a stronger cleaning. Nothing works better on the varnish then the alchol

[FlatheadTed]

When cleaning carb .pull the top off , undo the small jets & mixture screws ,blast out the holes with at least 100 psi ,As i said pull the top of the carb after running it see if the fuel level has dropped . ,Did the spark stay strong when Revved ?

[BIG MIKE]

yes very strong long Spark yellowish orange

[Mr 42]

The spark should always be Blue nothing else.
Replace Condensor and or coil.
I do it on that order since the condensor is cheapest :-)

[FlatheadTed]

Yeah should be blue .Did you try the jumper wire to the coil ,this could improve the colour of the spark, then do what Mr 42 says .

[BIG MIKE]

thanks Mr 42, Ted I have a new Coil and Condensor anyways, will change those, plus new plugs. A few other ? i need sum answers too
can I use premeum or super unleaded gas?
I have bubbles in the glass bowl , is that normal?
when I take off the air Breather on top of carb I hear snappy poping sounds , like on a frying pan, whats that all about. Thanks BIG MIKE

[FlatheadTed]

Ether gas is OK .The bubbles could be sucking a bit of air .run a hose from the pump to a safe place from the motor and catch some gas to see how strong the pump is,The spitting sound is pretty normal,