Mule spring maintenance

M274 Mechanical Mule Wanted, For Sale (NO AUCTION or EBAY), and Knowledge Base
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nickd
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Mule spring maintenance

Post by nickd » Sun Mar 14, 2021 11:54 pm

Welcome spring!
With warmer weather on the horizon its time to get our mules ready. Here is what I do. The mule gets started and ran a couple times during the winter. Don’t forget to check for the awful mouse nest on top of the cylinders. I check for air flow at the bottom of the cylinders at the openings of the cooling shrouds. If you notice reduced air flow ,remove the top cover and inspect. If you find one I use a shop vac and a coat hanger to fish out the junk from the top. Don’t forget to reach up from the opening in the shroud on the bottom. I also check for air flow at the opening as well.

Fuel. It’s best to keep the tank full to reduce condensation in the tank. Fuel stabilizer is a must. These engines were in use during the leaded gas era. I use lead additive and a shot of marvels mystery oil in the tank. Don’t have any scientific evidence for any positive effects of the additives but I have put 240 hours on the running motor it came with. I did change the cylinders, pistons with new cranks, and heads along with the fuel pump, both fuel filters and the carburetor when I added the new hour meter.the magneto was also rebuilt.

Steering box. Check sand add 90wt oil in the filler plug. I drain the steering box yearly to check for metal fragments. Steering box replacement parts are not easy to find so maintain what you have.

brakes. Check for signs of wear, adjust cables and don’t forget to use some graphite dry lube on the emergency brake cable.

Drop axles check and add 90wt oil. I drain them once a year to check for metal particles. I rebuilt my drop axles 240 hours ago yes they leak some but check the boots for tears.

Transmission I drain the oil yearly. If you shift roughly and grind the gears you’re in for some pita repairs. Mules are not racing machines.

Clutch. Check and adjust as needed.

Engine. I change the oil yearly. I add a shot of marvels mystery oil here as well. I added a spin on oil filter adapter 240 hours ago. Always pre fill the spin on filter. I check the oil regularly and look for leaks. It costs about 25 bucks for 3 quarts of Hd 30wt oil and the NAPPA 1515 oil filter. Cheap insurance for reliability.

Shift rod supports. Get under the mule and lubricate them once a year.

Steering tie rods. Not much to do other than check for extra sloppy ness in an already sloppy steering arrangement. According to the manual somewhere it states the amount of normal steering wheel play.

Tires. Check for proper inflation.

Front axle. Drain and add 90wt oil.

Spark plugs. I pull the plugs yearly and check for carbon build up. Re gap them and reinstall.

Electric start. Mine had a starer so battery maintenance is important. I opted for a small auto battery tucked up out of sight under the deck. Lawn tractor batteries didn’t work well for me.

Spare parts. I bring a magneto rebuild kit, spare spark plugs and my mule tools with me to shows. In the spare parts box I keep fuel and oil filters, a fuel pump, carburetor, extra spark plugs, air cleaner, spare rubber intake manifold hoses, brake shoes axle boots and spark plug wires. I have a pile of other parts but keeping the parts listed above will keep the mule running without needing to source parts should you run into a problem. I did rebuild my magneto at a show once. It ran fine at home once I got to the Aberdeen show one year it ran fine for the first day. The second day the mule lost considerable power (weak spark). I bought a rebuild kit from David Kelone and we rebuilt the magneto and was running in about an hour and a half. A couple of mule owners were on hand to witness the tutorial.

Maintaining your mule annually with periodic checks will make mule ownership a pleasant experience.
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Air Doug
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Re: Mule spring maintenance

Post by Air Doug » Thu Apr 22, 2021 2:55 pm

This is really helpful, thanks.

markrdje
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Re: Mule spring maintenance

Post by markrdje » Thu Apr 22, 2021 5:17 pm

Ya, I second that, my mule been setting a while(battery probably is dead)) this will help me alot
Thanks
change user name to mark

Chuck W.
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Re: Mule spring maintenance

Post by Chuck W. » Sun Apr 25, 2021 3:04 pm

Nick has covered the main maintenance items. I will add two more, from my own experience: check the rubber hose and clamps between the air filter canister and the left frame tube. Remove the drain plug at the rear of the right frame tube and check for water, might be a good idea to spray some WD40 into the frame tube, they rust from the inside out.


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