Motor stuck ??

[51chief9k]

I recently picked up a 1940 Indian Four and the motor doesn't turn over. Before I remove the motor and tear it down, is there anything I can do to troubleshoot the problem while the bike is still together? The kicker pedal slowly compresses under foot pressure but the motor isn't turning. With the spark plugs removed and the transmission in gear, rocking the bike back and fourth, the engine still doesn't turn. The bike has been stored inside for the past 20 or so years but was reportedly "running when parked". Other than normal carbon deposits, the pistons and cylinders look ok. Could it be a transmission or clutch problem?

[PaulCDF]

51chief
Nice find. I am assuming you have tried pouring/spraying your penetrating oil of choice into each cylinder and let it soak for a time?
Any oil in the crankcase?
Note the Library has some Indian 4 books

[51chief9k]

Hi Paul, Cylinders have been soaking for about a week, the crankcase does have oil in it. I didn't think about the Library, I'll check it out. Thanks

[PRG]

Howdy sir,

If you’ve been able to push it in neutral without a problem then the transmission is possibly OK as that leaves only one small component connecting it to the bevel gear and then motor as you see in my 441 below: the middle gear which is the slider. Unlike a Chief only dog engaging third, Fours are dog on 1st and 3rd.

What I find odd if your description is such - and not related to a locked engine - is you describe the kicker pedal slowly descending while the motor does not budge. Slipping clutch? With 16 springs on a stock application and 8 if fitted with any modern clutch available in the last 30-40 years, if anything your clutch should not disengage or slip as they tend to stiction weld themselves together under high clamping pressure especially if fitted with Chalfants or similar material and inactive for long periods of time. As an aside, don’t know if you observed when found/purchased that in storage they might have the clutch lock enabled at the pedal in the disengaged position to portend that sticking issue. This can lead to the ears breaking off or bending on the two clutch fingers. Unfortunately, any clutch issues require engine disassembly and pulling the crankshaft. All can be done with normal tools. You will need to bend an open 1/2 inch wrench to get the trans apart if it is found to be the issue.

Locked engines on Fours not having obvious ring/bore issues is unusual. The rarity of parts for these and if you were fortunate enough to have virgin cases not showing damage at #2 rod under the mag/generator pad or flywheel housing from a thrown drive chain then I would be tempted to take the most cautious approach to putting this machine back on the road. I merely confirmed my very original 440 at the link below the 441 ran at time of purchase, got it home, took it entirely apart to inspect before pressing it back into service. Good luck sir.


http://www.patwilliamsracing.com/194...dianfour28.jpg

https://petergz.smugmug.com/Motorcyc...0-Indian-Four/

[vtwin74]

Is your bike a magneto ignition? if so, it's somewhat unlikely but it does happen where the magneto will get hot enough to throw tar and essentially lock up the magneto thus locking up the engine. I know this because it has happen to me on a early Henderson.

[51chief9k]

The bike does roll easily in neutral, when I first looked at the bike, the clutch pedal was depressed and locked (disengaged). as stated, I will have to pull the motor if I determine the problen is in the clutch. This is a magneto ignition so I will look into that.
Thanks for the help.

[PRG]

Howdy sir,

On rare occasions distributor models will experience binding at the generator- to-distributor drive interface if not lubricated at the grease fitting. Easy to determine as both mag and generator models use a rubber coupling at the drive shaft which can be observed to wind up and twist when kicking it over. Obviously, this isn’t a “hard” lock up, so to speak, rather growing resistance as one attempts to kick a motor suitably burdened, over.

If by chance you need to remove your mag you’ll note, unlike early Fours, there are no timing marks. 38 and later machines are not tuned with much interest for performance unlike their “upside down” predecessors with only reference to 5/8” inch piston distance to TDC for 45 degrees full advance with a head removed (this a rough approximation in my opinion). That an obvious very involved process to obtain this measure. To get one merely running for baseline reference you can remove the timing cover and easily observe cylinder #1 rod at TDC for ignition at full retard.

Also, interested at how someone determined the cylinder bores were OK with the heads fitted. As observed below, the spark plug access is hindered by a necked down port an inch or so below the last thread in the head and very offset to the cylinder as it is above the intake valve in the image below and the bore is at the bottom. Even threading a scope through an open exhaust valve with the header removed does not reveal much.

http://www.patwilliamsracing.com/194...dianfour57.jpg

[51chief9k]

Hello Peter, Thanks for the insight on the cylinder bore, I'm not sure what I was looking at but I have a much better idea now of what is and isn't visible. The good news is that after a couple weeks of soaking the cylinders, using a heat gun to warm the motor and oil pan, draining the oil and replacing it with fresh oil, I got the engine to turn over. The clutch is stuck, (the motor turn over when kicked with the clutch pedal both engaged and disengaged) and I have no spark at the magneto. Next is the mag and fuel system, then hopefully I can hear the bike run and see about freeing up the clutch.
Thanks again,
Steve