1872 is parked in the yard wearing a blue cape
 

I had been mowing about an hour when a friend stopped by so I stopped mowing to have coffee with him. That was the good news, the bad news is my tractor doesn't want to restart. Starter motor runs but doesn't engage with the flywheel. I turned the engine by hand to eliminate the remote possibility of flywheel teeth missing - no change. I think maybe the starter shaft is dirty from all the dust that gets churned up when I pass thru a spot where there is no grass growing. Anyway it looks pretty involved getting to the starter drive and shaft on this Magnum engine. Do I need to remove the engine to get the tins off? Is there a shortcut or work-a-round to cleaning the starter shaft or replacing the starter?

The 1872 sets in the backyard under a blue tarp until I can figure out/or get help with what to do next. It's raining hard and dark out so any fix is postponed until tomorrow. Lawn half mowed, now I wish I had picked up a real nice 2284 last week as a spare.

take the left tin shield off and you can look in and see the starter, spray some pb blaster on the starter shaft and try starting , leave the tin off temporarily it may be full of dirt / mouse nest in there , blow everything out good

You summarized what my intentions were, I was asking how to remove the tins. Maybe the heat box around the muffler has to come off first. Do you know if that it true? I can see much of the starter motor without removing any tin but the drive end is partially covered by the side tin and the end of the starter shaft appears to be covered by the flywheel/blower sheet metal. Doesn't seem to me that removing only the side tin will allow me to spray anything on the suspect dirty shaft end.

When I saw that it was going to be more involved than I initially thought I tried the starter one more time (tried it 20-30 times yesterday) ... well it did engage. I put the spark plug back in and a couple of bolts back in the side tin so I could finish mowing and then parked it in the garage were I could better work it.

I still would like to hear from someone who knows (from experience) if the motor has to come out to replace the starter and/or clean the drive end of the starter. Thanks for first hand knowledge on this, Steve

There are those with more experience and the right wrenches can remove the starter without raising the engine. Last time I did one, I removed the six bolts holding the motor plate in and then jacked up the engine, just enough to get the starter out.

yes the engine needs pulled to change the starter , no the muffler tin doesn't need removed to remove the side cylinder head cover , remove the bolts at the top and on the side and the spark plug. there are 3 bolts in above the frame that can be a pita. you can leave those in and just bend the metal out away from the head and you'll see the starter drive......how's around 40 yrs. of working on them rank me for having first hand knowledge.............I have changed the starters in the frame but it isn't easy and it'll need a good cleaning anyway . remove the flywheel and check the magnets to see if they're loose too

Steve, It can be done in frame but it is almost as fast to remove engine. It looks and sounds harder than it is. Disconnect battery, four bolts and headlamp wiring to remove hood and grill, six bolts on engine plate, two bolts on engine plate are right above front axle and are a little hard to get at, it helps to jack up front of tractor. Then four bolts on rag joint at front of driveshaft, choke and throttle cable, than engine wiring harness and starter cable. slide engine ahead to disengauge drive shaft and lift it out. Hope you have a cherry picker as it is heavy. While engine is out check rag joints and drive shaft coupler balls for and replace if needed. Pull all tins and check for oil leaks. You might be surprised what you find under the tins. Good luck with your project. It is not really as bad as it seems.

:IH Trusted Hand:

Thanks to all for your help. Farmall Fred you nailed it/speak my language and added some encouragement too - GREAT [ I'm saving your post for the day I decide to tackle this. ]

I have about 300 hours on this tractor since I bought it. Previous owner (a tractor mechanic that buys and sells tractors as well as repairs them for customers) had several Cub Cadets, Deeres and a big Farmall in his shop when I went to get this 1872. He had done a fair amount of work on it, piston rings and a new starter were included. No engine oil leaks and battery charging is fine.

Update on starter failure to engage
 

Update on starter failure to engage

I bought a new starter for my tractor but didn't install it because it continued to work. Decided to wait until the problem returned. This past Saturday the problem returned. My friend (another 1872 owner) came by to help me pull the engine to put it in. We pulled the deck, disconnected the lights then as farmall fred outlined started to disconnect the battery. Found a loose positive cable at the battery. Surprise, surprise! My friend cleaned & tightened it and said "try it now" - started up just fine. We surmised that there was enough juice for the solenoid and starter to turn but lacked the ability to throw the drive pinion into the flywheel gear. I'll keep the starter on the shelf but for now I believe the problem is solved. So far, I have a dozen or more trouble free starts to bear this out.

Good news:beerchug: