H Low power under load

Tom Lane · Dec 7, 2009

Have an H which misses and lacks power under load, has trouble pulling itself when in high gear ETC.. Have cleaned fuel system, and checked igition timing. Cannot understand what problem is. Have changed carbs,plugs, etc.. Seems to smoke(black) and miss bad, but idles and throttles great at standstill. Help! Would like to use tractor!

D7fever · Dec 7, 2009

adjust your carburetor again for under load, check your plug wires, if they are radio suppression carbon wires, they might be bad, get new ones with copper or steel. Did you put new spark plugs in? I use non resistor plugs. I also had the same problem in my H with Champion spark plugs , changed to different brand never had another problem. I know there are a lot of guys that don't think that about Champion plugs, but I don't use them anymore. If they work good for someone great.
Good luck.

gene bender · Dec 7, 2009

Rule # what is the compression test say.

Bob · Dec 7, 2009

GREEN "H", RED "H"???

El Toro · Dec 7, 2009

You need to check the fire to your sparkplugs. Pull off a plug wire and hold it about 1/4" away from plug. Should have a good hot spark. You may be overfueling the engine with having black smoke. You may need to close the main jet adjusting screw to lean it out some. Just close it 1/2 turns until it quits smoking. If you have weak fire could be your coil is getting weak. Hal

Jerry Coulter · Dec 7, 2009

Is the air cleaner clogged? Disconnect the cleaner from the carb and see if you have increased power.

John B. · Dec 7, 2009

Yes always test the compression before a tune up! Back fire may be caused by a bad intake valve or play in the distributor drive train.

Low Octane gas can cause film to build up on the spark plugs that can't be seen but cause them to miss also.

showcrop · Dec 8, 2009

I'll just insert the 1 after # and add rule #2 what does the vacuum gauge say.

Anonymous-0 · Dec 8, 2009

Thanks d7fever, I also had a problem with Champion plugs in a car. have autolite plugs and have tried old and new with no change.Have run it without air cleaner and muffler, ho change.Does not smoke accept when it misses so hope it is not compression. Will have to check that and vacuum. Thanks for reply!

Anonymous-0 · Dec 8, 2009

Thanks Jerry, Have run it without air cleaner and muffler no change.Runs great at idle and throttles up full without a hitch.

Anonymous-0 · Dec 8, 2009

Thanks Hal, Have swapped coil with my 8N and no change, have rebuilt and swapped carbs also no change. Will check for spark again looked ok to me.Have adjusted main in and out.

Anonymous-0 · Dec 8, 2009

It is a Farmall Red H Bob Thanks

Anonymous-0 · Dec 8, 2009

Thanks Gene, Have yet to do that always scares me to do that, no smoke so will hope. What is acceptable? Around 100pounds with less than 20 difference in cylinders? Thanks

Anonymous-0 · Dec 8, 2009

Thanks John,Will be trying a compression check and vacuum check next.

Jerry Coulter · Dec 8, 2009

It doesn't sound quite like a problem I had with an H once. A farmer brought it in to get tuned up. I put it on the dynamometer and couldn't get power. Finally dropped the carb, stuck my finger up the manifold intake, and it was closed down to a small hole. I had to remove the manifold, take a hammer and chisel, and chip out a lot of carbon. Then the power got right. It seems that back then, FS gasoline was especially bad to cause this.

H Low power under load

Tom Lane

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D7fever

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gene bender

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Bob

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El Toro

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Jerry Coulter

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John B.

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showcrop

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Anonymous-0

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Anonymous-0

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Anonymous-0

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Jerry Coulter

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