Houston we have a problem…  This thing has too much compression and the stock M starter just doesn’t have enough go-nads.  Result; she won’t spin over.  That is what I’ve been fighting for the last week.  A weak starting system.

Once I had the engine buttoned up I could easily spin her over by the fan and pistons, valves and cylinder head all cleared each other (thank God).  I set the injectors to 1.460 and set valve lash, cold, at .013.  I went through the manual procedure to determine how the engine was timed without taking it apart and the results say that the engine is timed “straight up” or standard.  One more round on the torque wrench to make sure everything was tight (190 ft-lb isn’t a picnic on those cylinder head bolts) and we were ready to see if she’d run.

The engine turned over but slowly.  Then the standard push button solenoid sparked, smoked, glowed and I can still smell the thing as it is lying on the shop floor.   I thought, for sure, that the starter was shorted somewhere internally and was just drawing too much current.  My load tester and multi meter both said the battery was good and fully charged and all of my battery cables measured nearly zero resistance. So I pulled the starter and disassembled it.  The commutator has nothing left to turn off of it so the armature is toast.  But I didn’t find any internal issues other than that.

To systematically eliminate issues I robbed a starter off of my other M, which I know is good and installed it.  Still no joy.  Replaced battery cables with larger ones.  Still no Joy.  Installed a standard automotive 4 post solenoid to remotely actuate teh starter with a remote button and finally I robbed the 2nd (new) 965 CCA battery from the 560 Diesel and put her into service on the M.  Finally she spun over and to my surprise the little Detroit came to life.  The little engine must have been full of fuel from turning it over continuously because it wet stacked and blew raw fuel all over the shop ceiling, the tractor, me and everything else in a 10 foot radius and filled the shop with smoke.  I could have killed every mosquito for a half a mile if this had been Summer.

I let her run for a minute and then killed her.  After that the battery was getting a little low and the starter rather hot and I never was able to spin it fast enough to get it to catch again.  Time for a starter with more oomph.  This though is turning out to be more challenging than I had anticipated.  Short of some pricey starter put together to turn over big inch M pulling tractor engines there isn’t anything commercially available.  Being the never satisfied engineer that I am…. I am now on a mission to “cobble” together a later, more powerful, starter from something like a 560 Diesel so that it will fit the M bell housing and ring gear.  So we need to find a motor that will accept the 2 bolt nose cone and M bendix and spin CCW… That will be another “how to” post once I get it worked out and proven.  I have a spare D350 starter from a Super WD9 that we’ll be experimenting with next week and a few other starters of various flavors to do the same with.   So stay tuned for this continuing journey.