Worlds hardest starting Mule

[m56-mike]

All
so i bought a non-runner from a guy in Utah about a year ago it is a 4-wheel steer 2-cylinder unit. it had a nonfunctioning starter and alternator kit i replaced the starter... It had been a father son project, and they had been "fixin" lots of stuff. They had heads shimmed that did not need shims 2 bad magnetos a huge air leak in the intake tube. compression was just ok...
So I rebuilt it.. New heads cylinders matched pistons new lifters (from emory good correct stuff). New carb rebuilt fuel pump the whole 9. Presently has a new old stock carb installed. New pickup tube assembly in good clean fuel tank.
long story longer it has tons of compression 120's per side. It runs like an animal, once running, has good power no leaks no smoke. However, i have to crank forever to get it to run... Especially cold it's like it's kind of running it won't quite go then finally it does, then it runs like a sewing machine... it starts ok warm not perfect but will start. It has about 6 hours on the rebuilt motor//

What i know
-timing clicks between the marks of 28/18 with the factory marks lined up
-Fuel squirts out of the bypass tube 13" high while cranking
-choking makes it worse
-holding the throtle wide open when cranking makes it worse
-John Emory says the mag tests perfect

What i have done
-2 different carbs
-2 different fuel pumps
-lots of different Plugs
-Timing marks are lined up Mags flat i have tipped it every which way
-ive unhooked the switch mechanism and the hour meter ive been told they can short out
-Ive blown air into the tank forcing lots of fuel to the system while cranking
-plumbed a 3psi Fuel pump in line before the filter supplied fuel from a nurse tank.. Same deal
-Ive tried to hold and pin the throttle in every position assuming perhaps the governors not doing something correct

What are we missing here boys ready to push it off a cliff

don't those mags retard timing at low rpm to promote starting?? Ever see that goofed up?

 

[NDT]

Sounds like the only thing you haven't eliminated as a cause is the plug wires. Suggest you grab some solid core ignition wire and stuff it in the plugs and mag and see if that changes anything.

 

[SolaAesir]

I'm not a great (or even good) mechanic, but this

-choking makes it worse
-holding the throttle wide open when cranking makes it worse

would have me making sure it's able to get enough air. Things getting worse frequently means you're exacerbating the existing problem.

 

[M813rc]

Mules, in accord with their name, can be stubborn.

Back when I drove Mules in the Marines, our standard start procedure was -
Leave the accelerator pedal alone
Full choke
Ignition switch off
Four pulls on the starter rope
Ignition switch on
1/4" to 1/2" of choke (depending on the likes of the particular Mule)
Pull the starter rope and it fires right up

My personal Mule has electric start. Following the same procedure, but substituting a 1-2-3-4 count while pushing the starter button instead of the four rope pulls, achieves the same results.
Mine likes 1/4" of choke.

If I don't follow that procedure, I can crank on it all day and it won't want to start.

Cheers

 

[m56-mike]

Guys

A bit of an update i did the "start over" deal last night Plugs Ohlm the wires check for loose fuel fittings run a compression test.. AAAAAAAAAAAHHHHHHHHHHHHH uUUUUUUUUUGGGGGGGGGGGGGGHHHHHHHHH.. the left side cylinder when you l;ook at it from the rear hasa whopping 65 PSI compression.. It very occasionally 1 or 2 out of ten spins will go to the 120's .. I have an intake valve hanging open or a crappy lifter or something.. Ill get tearing into it ang get the group an update.. Never forget the "O" in NOS is for "old"

hate to pull it apart its all painted up like an actress wires & hoses tied up... Everything in its place.. Well at least now i know

 

[nickd]

Sorry to hear about your ordeal. If memory serves me correctly, you may be able to remove the cylinder head with the engine in place. I will look at mine shortly.

 

[glcaines]

Any updates? My experience with Mules is that if everything is correct, they will start easily. My Mule has electric start. When cold I use full choke and don't touch the throttle. It starts after 2 or 3 revolutions of the engine. If it has been sitting for a month or more, it will take 5 or 6 revolutions of the engine. Once started, I go to no choke, and it runs great. When warm, I never use choke - it will start with one revolution of the engine. I have always been amazed at how easy my Mule starts compared to other small engines I have.

 

[m56-mike]

Guys
Yes i have updates... IT LIVES Haaa haaaaa haaaa.. So i did a rebuild on this mule motor (the previous owner had just done it). The cyliners and pistons ere mismatched and very tight. Ebay stuff "A"'s mixed with D's, anyway i bought new matched cylinders from Jon Emerey new heads new Lifters. As i ran this after the work it became harder and harder starting. I finally found i had 135LBS compression on one side & 80ish on the other. So i put the motor back on the stand. As it turns out i had a NOS cylinder head that was bad, the aluminum blank that they started with was drilled off center. so if you can imagine looking down on this head the bore was literally into the mounting holes on one side while being 3/16 off he holes on the other. it was off center. This let combustion gasses get past the should be seal from the top of the cylinder to the head.
Now this gets deeper because i noticed the rings had not seated on that cylinder, it had almost 6 hours run time yet with the new head installed as i rolled it over (on the engine stand. I got all kinds of compression on the good side, and heard a loud Hiss on the bad side (what was the bad side).. The hiss was coming from the crank vent tube that feeds back into the air horn on the carb.. Keep in mind i was in the process of reinstalling all of the shrouds on thta frigging exhaust all installed all tubing etc. Once i found that leaking head i stopped. So i tore it all back apart i was certain that i must have had broken rings or something. Took it all back apart using (mommys car words) as my grand daughter might say. Rings were fine? Piston and cylinder looked perfect??? SO...i did notice there was a slight drag on that connecting rod / Crank connection. it seemed to roll not as freely as i thought it should with all new everything. Turned the motor over and pulled the bottom end apart expecting a smeared new rod bearing id guess... Hey maybe it had low oil press on first start up.. Bering looked fine but it was tight. So i took 1000 Grit we dry wrapped the journal on the crank with a shoe string and 1000 grit and polished the crap out of the crank shaft. None of the local shops here knew what a plasti gauge was so i just cleaned polished and reinstalled it freed right up.
My theory there is / was if there was drag on that rod it would in essence be lifting up and smashing down that piston vs smooth operation. Could this interfere with rings seating?? well i was not looking to do this all a third time so i was probably going a bit overboard. Re-assembled. got ready to reinstall.
Next challenge my flywheel was broken.... Yep the previous owner / hack had not lined up the keyway properly when he reinstalled the flywheel. I never removed it. My mistake clearly. The long flange taper fit snout on my flywheel was broken with a c

 

[m56-mike]

So the OTHER thing we found is / was i Had a broken flywheel, yep never took it off but the previous owner has not lined up the keyway correctly and pulled the flywheel on with the bolts just as they tell you never to do. it had a rattle i thought was a transaxle bearing not great, nope busted flywheel. so got a flywheel clutch pressure plate throw out & pilot bearings. All properly installed.

we are now running well i will do some short cycle oil changes cause im a bit of an over-dooer. It feels like were making good compression on both sides now

 

[glcaines]

I'm glad to hear that you got it sorted out. You never know what a previous owner or mechanic has done before you get the equipment.