H in trouble

Hey I have an H that had sat around 15 years and I just got it started again. The problem is it is running really rough, it is skipping badly at all RPM's although it tries to hit on one more at lower RPM's, I filed the points and changed the plugs and the oil with no difference. My question is, is there a way to tell if I've got valve or head gasket problems or if it needs wires cap rotor etc... there is no smoke , no water in the oil and as far as I can tell no oil in the water. I have spent a fair amount already and don't want to do a tuneup if it's a lost cause. Thanks all, you'r feedback helps a lot with these old tractors

you can run a compression test and see if there is a bad cylinder or valves. firt, isolate the bad cylinder. with the engine running, short each spark plug with a screwdriver to ground and listen for a change in the engine. if you get a plug that makes no change, start with that cylinder. pull the valve cover and re- adjust the valves too.

i would remove the valve cover and make sure you dont have any stuck valves.

Lots of good advice here already, troubleshoot, don't just change parts that you aren't sure are bad.

can't afford to that's why I am slowing down to see what I have here, spent enough already, not to mention the tires and rims are in sad shpe. Thanks

I would use a spark tester to make sure you are getting good spark to all cylinders first off, Then I would take the valve cover off and make sure all the valves are free and moving as they should. Next on my list would be a compression test. One of these should reveal a problem.

One that has sat that long could well have sticking valves and I know the rings will be sticking. I would pour some ATF in each cylinder and a little down the exhaust pipe and let it sit 24 hours. Then spin it over with the plugs out, put the plugs back in and try it again almost bet it runs better

My experience with H's is that the carb is probably gummed up and the float could be sticking from sitting and having the gas in the carb dry out,leaving it gummy. Get some carburator clean and spray it in the throat of the carb with the tractor running, the higher the RPM's the better.
In the case of valves sticking ad a can of risolone,or even duralube and let the engine run ,work it a bit if you can and sticking valves usually let loose. You can always remove the valve cover and watch for movement of the valves,like others say,do some diagnostics before throwing parts at it.

Also you can drain the oil with engine warm refill with atf and run it just above idle for 15 mlnutes drain refill with fresh oil but substitute 1 quart with atf or marvel mystery oil. Also add a pint to the gas.

some basics.
1.) makes sure all ignition components are in good working order. Plugs, wires, points, condensor, rotor, and cap. No corrosion, good connections. I realize that you don't want to waste money, but there are no shortcuts here. Clean it shiny clean or replace it. 15 years of sitting WILL take it's toll.
2.) Take valve cover off, and either start it or turn it over by hand. are all valves operating and do they have full travel. Even if a valve is moving, it needs to have full travel and close completely.
3.) Check fuel delivery. Clean out carb, sediment bowl, and lines. New fresh gasoline is an absolute MUST.


After all this, if you still have issues, post back and we will go from there.

ps. if you find a stuck or sticky valve, apply your favorite penetrating oil FROM THE TOP. Also, you can use a heat gun or propane soldering torch to heat up the valve guide. Alternate heat and penetrating oil. Moderate to light raps with a brass hammer can start to break a stuck valve loose, BUT DON'T OVERDO it. For a really badly stuck valve, you will have to remove the head. It also helps if you can keep it running long enough to heat up the head before you start this, it will really help. running the engine with the valve cover off is not a big deal for this procedure.

Had the same symptoms on my H. It sat for 25 years. Turned out that #2 intake valve was stuck open. Allan.

A distributor shaft/bushing, loose at the points/cam, will cause that issue as well as the ideas below. If you can wiggle it up and down, and or toward the engine and outward, and feel ta little play, it is bad. That shaft needs to be within .001" to keep the timing correct. Jim (visiting California)

actually I added Marvel mystery oil to the old oil and ran it before I changed it and then added some to the gas, maybe I just havn't run it enough yet... The back rims are rotted out bad around the valve stems so I didn't want to drive it much and I wasn't sure about damaging the engine running it skipping so bad. Maybe I'll check out the valves before I do anything else, it really wants to run

Hey guys new info, I just noticed that the coil is cracked I'm told it's surprising it runs at all! I have one off an Allis D-19(both 12 volt) I'll put it on to see what happens that should tell me what I have to work with without having to buy things I don't need. Thanks for all the responses, it'll be a long road yet the rims are rotted seriously around the valve stems and when I drained the rear case a huge amount of water came out and then finally muck. Anyone know how much gear oil it holds by the way? But at least it will be nice to hear it run well, it's amazing how well it starts in spite of all. Thanks Eric

Six gallons on the rear gear oil and I believe you have two drain plugs; one on the back and one up front. The level check pipe plug is on the left or clutch side - good luck with your other issues, Hal.