Erratic engine firing wd 45

Sat in a pasture for 3yrs. I do not know who the previous owner was except the person who gave it to me. Starts easy, while I have never had to hand crank anything I think it would start. My problem is every 5 to 30 seconds it pops through the exhaust. Tonight I drove it home in the dark and did not notice any spark jumping. It is converted 12 volt, new wire harness, new coil and plugs and condenser, cap and rotor. Plug wires were slightly chewed on by pack rats hence the 12 volt conversion. Back to the miss fire. No spark jump in the night but misses every 5 to 30 seconds and pops and I can see fire out of the exhaust. Sticking exhaust valve? Timing off? Maybe a carb issue and I say that because pulling chock rod out doesn't seem to drastically change things. To me it seems to be running rich. But it does start, idle and run like a sewing machine except for this occasional miss.

Running lean will let it pop in the exhaust too when it misfires and gathers fuel in the exhaust manifold.

Gerald J.

I would guess sticking valves. Will proably clear up after more running.   Bill

If you think its the timing loosen up the distributor wile the tractor is running and turn it left and right slowley and see if it smooths out.

Hello, Went over tractor to possibly find what was wrong with the misfire. Correct me if I,m wrong but shouldn't the firing order be 1-2-3-4 with the front cylinder toward the radiator be #1? I saw this information somewhere in  my manuals but can't find it. Before I try changing plug wires around I thought I would ask. Sitting in the garage right now chomp"n at the bit. It is currently wired 1-2-4-3. Please help before I give up on all hope except for a valve job which I can't afford at this time. It's a WD 45 226 ci high octain built in mid 53.

Thanks Orange but it's not what I wanted to hear. Will continue to run it slow. But i did get ahold of a friend who still has a timing light but busy this weekend so it will have to wait. Darn it.

what rpm or rpms are you getting the pop? Is the pop slight or loud? Could it be called a flutter type popping? Some flutter type sounds at low rpms would be normal. Louder pops at a higher rpm would lead me to a compression check for a leaking (non seating) valve. Timing will do it also. Hard to hear sounds thru other peoples ears. (:^D

Edited by Dick L - 30 Sep 2011 at 7:42pm

If you are getting a loud pop and fire out the muffler, then my first test would be like Dick said, a compression check followed by a leak down test.  Those will give you a good idea of the either the valves or the rings.  If you get good numbers with this non invasive test, then you can dig deeper into other things.  However that being said, I think you idea of chekcing the timing is the first priority.

Yes Orange , Dick is probley right. I'm just in denial.

Thanks Gerald, taken into consideration when I try this tomorrow morning. The Mrs has book club in the morning till we leave for inlaws for fish and game feed. Either way this weekend is looking good and have some good info before I have to have a real tractor mechanic look at it. Nice guy in his 70's but has a wealth of info. Does it for a hobby. I just for the life of me can't figure out where you guys get the time to restore or maintain these tractors. If I came home with another tractor it would be me and it sleeping under a bridge. The Mrs just does not quite understand LOL. Just kidding but I've seen some serious collections since I've joined. Have ya'll a good evening.

Thank you for being patient with me. Sat morning I tried adjusting carb main and idle adjustments but no real changes in erratic firing. But then it all of a sudden it completely quit. Took #3 and #4 plug wires off and held to valve cover and no spark. What the heck? Returned to original carb settings still no fire or spark. Today I went through it with my voltmeter and everything was as supposed. Pull distributor cap and rotor and found the dust seal had come out and cover the rotor contacts. Cleaned crude off and tried to replace dust cover without the seal fibers coming out. They still did but it fired right up. Should I lube the dist shaft coming up to the rotor and with what? I'm ready to pull this seal and see if it consistently fires. Maybe I could pull this fiber seal and turn it upside down and lube? Any coments welcome. Thanks, Butch

Thanks Brian, I was told points, condensor, cap and rotor are 3 yrs old. They look good. I checked gap on everything. I have what I think is the seal on the dust cap, the fibers or seal in the dust cap coming out and  covering the rotor contacts if I'm seeing things right. I'm talking about the bottom of the rotor where it makes contact with the dust cover under the rotor. The original mess covered half over the rotor contacts. I appreciate your help. Maybe I'm wrong but I didn't know if that seal is conductive or not. I almost feel foolish for even posting this. Because I do not know how the rotor makes contact with the points.

Points plugs cap and condenser that sat out for 3 years in all kinds of weather draw moisture. Check the simple things off the list first. A plugged/lean carb will cause it to shoot fire at high speed. Did you clean the tank, carb, and sediment bowl/shutoff valve? My WD45 draws moisture and is very picky about fresh gas.

calmers bob hello. i guess the point I was trying to make wasw hat is in question is the at the bottom of the rotor could not make contact to #3 and #4 contacts on the bottom of the rotor because of this fibrous materail coming out of the center of the dust shield. It completely covered a 1/3 of the rotor contact area. pulling it and cleaning and sticking the fibers back into the dust cover it fired right up. but it still missed like it always had and when to pulled the rotor again the seal under the rotor was covering the contact area between rotor and dust cover.  If I'm not mistaken those contacts on the top of the dust cover (star Shaped should make contact with the bottom rotor tab. Also I have already checked the above posts. The only fuel problem I had was the previous owner relined the tank and I was getting residue from that in the fuel blow. New pliug, points both gapped. Dist cap and plug wires look good but? Rewiwered 12 volt. Used volt meter to confirm new switchs are working. I wish I could show you this dust seal in the dust cover that I'm talking about Butch

The dust cover doesn't have contacts that contact the rotor. The shiny material is a snap ring to hold the seal in place.The only rotor contact is at the top and side. Bob