'46 starts great cold but just cranks when warm

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   My 1946 Willys (6-volt) starts great, but if I shut it off it won't restart for hours -- it'll just crank until the battery goes soft. Interestingly, in this state it will still quite readily bump-start.

Could it be that the starter is drawing too much juice when the engine is hot, such that there isn't anything left for a spark? What is the best fix for this? Are starters still available? All I know is it has a foot switch to operate it. Looks like a black cylinder.

Thanks,
Doug

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Doug65 Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 29 July 2008 Location: Appleton Status: Offline Points: 2	Post Options Post Reply Quote Doug65 Report Post Thanks(0) Quote Reply Topic: '46 starts great cold but just cranks when warm Posted: 29 July 2008 at 4:13am
	My 1946 Willys (6-volt) starts great, but if I shut it off it won't restart for hours -- it'll just crank until the battery goes soft. Interestingly, in this state it will still quite readily bump-start. Could it be that the starter is drawing too much juice when the engine is hot, such that there isn't anything left for a spark? What is the best fix for this? Are starters still available? All I know is it has a foot switch to operate it. Looks like a black cylinder. Thanks, Doug

TERRY Members Profile Send Private Message Find Members Posts Add to Buddy List Member Sponsor Member Joined: 22 May 2007 Location: BOULDER COLORADO Status: Offline Points: 3401	Post Options Post Reply Quote TERRY Report Post Thanks(0) Quote Reply Posted: 29 July 2008 at 11:17pm
	Sounds unusual, guess starting at the basics when the engine is warm, verify spark and fuel delivery. Maybe on a coast start higher rpms are achieved and the fuel flow is better? Check points etc, could the coil be warming up and delivering a weak spark/ All guesses, just approach it in a systematic way to find the problem, you already know the continued cranking doesn't work. Another place to look, make sure the connections to the battery, starter, foot switch are all sparkling clean and tight so the starter gets a full 6V. After all the positive connections and grounds are clean and tight recheck for voltage drops in the circuit.I guess that is the simplest and most likely to help place to start Terry
	BOULDER 48 2A

Jus*Jack Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 15 Mar. 2007 Location: so. Georgia Status: Offline Points: 1841	Post Options Post Reply Quote Jus*Jack Report Post Thanks(0) Quote Reply Posted: 29 July 2008 at 11:27pm
	I agree with Terry on the starting with "simple things first"...and I'd sure be looking at the grounds for everything that relates to the starter...from the battery to the floor starter switch and the key switch...and make SURE that they are making good metal-to-metal contact. One of the things that seems to confuse a lot of us amateur mechanic/electricians is that the BODY (Tub, fenders, etc.) IS A WIRE!!!! Not truly a wire, but it is used in lieu of the ground wire, to get the negative side of the battery or generator to anything else mounted on the Jeep. Lights, starter, electric wipers and horn, etc. Another simple item to look at would be to replace the condensor. They're notorious for causing little problems like this, and they're just about dirt-cheap. Check the one you've got, first, to be sure that it's well connected (clean metal-to-metal again), and if so, then pick up a replacement, and try that. It's a pretty cheap and simple approach.
	Seeya! <Jack> '48 CJ2A 197207 "Junebug" '48 CJ2A 191237 "Turquoise"

Doug65 Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 29 July 2008 Location: Appleton Status: Offline Points: 2	Post Options Post Reply Quote Doug65 Report Post Thanks(0) Quote Reply Posted: 30 July 2008 at 6:00am
	Interesting points to ponder and check. I have a couple of follow-up questions: - How does one best check to see if the coil is heating up and delivering a weak spark? I can wield a multimeter as long as I know what to look for. Or is it easier to replace it? - I am willing to purchase a new coil and condenser to see if either is the problem. What is the best source for parts like these? I've not been able to find one online. - Is there a way to eliminate the starter as being a part of the problem? My gut says it's being a power-hog and robbing the spark. Of course my gut is larger than I'd like and often incorrect. - I will remove, clean, and reattach all electrical contacts in the meantime. I'd be surprised if the problem resides here though. This jeep was restored recently and is immaculate. It even has the original 1946 canvas. After driving it all around the area yesterday (being careful not to stall it) I'm all the more appreciative. - Has anyone noticed a fair amount of heat transfer through the firewall? I was regretting the sandals I was wearing. What is a good temperature for this engine? It was sitting around 180 deg. F mostly, which seems fine to me. - Vaporlock? Maybe, but then it wouldn't bump-start. No, an electrical problem seems the most likely.

bkreutz Members Profile Send Private Message Find Members Posts Add to Buddy List Member Sponsor Member Joined: 17 Oct. 2006 Location: Fruitland Idaho Status: Offline Points: 7037	Post Options Post Reply Quote bkreutz Report Post Thanks(0) Quote Reply Posted: 30 July 2008 at 6:18am
	Doug, I'm thinking your gut is right, if it was vapor lock or an ignition problem, it wouldn't bump start that easy. If it were a ground problem, it wouldn't start that well cold. One thing you could do is find a shop that will do a starter current draw test, not an involved deal, amp probe around the cable to the starter, if possible test it cold and hot, you might have a starter that is indeed drawing all the available current when hot. Some modern starters will do this as well (especially when some "well meaning" mechanic left the heat shield off when he replaced the starter.) HTH
	Gale 47 CJ2A 142857 47 Bantam T3-C 16271 Photo page http://bkreutz.smugmug.com/

TERRY Members Profile Send Private Message Find Members Posts Add to Buddy List Member Sponsor Member Joined: 22 May 2007 Location: BOULDER COLORADO Status: Offline Points: 3401	Post Options Post Reply Quote TERRY Report Post Thanks(0) Quote Reply Posted: 30 July 2008 at 3:00pm
	A bit of resistance in wiring connections can cause voltage drops in the circuit that will slow the starter and weaken the spark. Electrical circuits develop higher resistance when they are hotter and that can worsen the problem. You can of course remove the starter, dismantle it and look for shorts in the field or armature, but I would think that a starter that runs isn't shorted but if it spins slowly has low voltage. A recently restored vehicle isn't a guarantee of good electrical continuity, fresh paint can make for bad ground connections at the engine or the frame connection. Are the battery cables and the braided ground from the engine to engine mount bracket of the proper gauge and are the connections paint free? Terry
	BOULDER 48 2A

Jus*Jack Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 15 Mar. 2007 Location: so. Georgia Status: Offline Points: 1841	Post Options Post Reply Quote Jus*Jack Report Post Thanks(0) Quote Reply Posted: 30 July 2008 at 4:09pm
	Condensor? Have you checked with NAPA, or Autozone or O'Reilley's, or Advance? I don't recall where I got my last one, but they're commonly-available, as far as I know. Might also want to do a little bit of searching here on the Page. I know that it's been discussed a number of times.
	Seeya! <Jack> '48 CJ2A 197207 "Junebug" '48 CJ2A 191237 "Turquoise"

X007925 Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 15 Aug. 2005 Location: Lavallette NJ Status: Offline Points: 167	Post Options Post Reply Quote X007925 Report Post Thanks(0) Quote Reply Posted: 30 July 2008 at 7:54pm
	So you don't feel alone I have the same problem. My 47 starts up with two or three shots on the gas pedal when cold but is a bugger to get restarted after a warm up spin. I changed plugs, points, condenser, cap, rotor, and coil and same issue. I get an "easier" restart when I remove the air horn from the top of the carb. I suspect mine to be a fuel issue where too much fuel is in the carb at shut down , or I get a drip,drip,drip from the carb bowl after shutdown. Mine "usually" restarts after 30 minutes with no issue. Rich
	Rich 47 sn 140278 on road 47 junker w/f-head sn 119281 48 project sn 210391

TERRY Members Profile Send Private Message Find Members Posts Add to Buddy List Member Sponsor Member Joined: 22 May 2007 Location: BOULDER COLORADO Status: Offline Points: 3401	Post Options Post Reply Quote TERRY Report Post Thanks(0) Quote Reply Posted: 31 July 2008 at 12:51am
	X007925, Check the carb float adjustment. Terry
	BOULDER 48 2A

hillbilly21 Members Profile Send Private Message Find Members Posts Add to Buddy List Member Sponsor Member Joined: 18 June 2006 Location: USA Status: Offline Points: 4964	Post Options Post Reply Quote hillbilly21 Report Post Thanks(0) Quote Reply Posted: 31 July 2008 at 1:11am
	GOTTA GO WITH JUS-JACK ON THIS ONE.. SOUNDS LIKE A CONDENSER !!!!!!
	1946 CJ2a POW-MIA 51 M38 ORIGINAL PRES NCFFC www.eastcoastwillys.org hillbillystoys.phanfare.co

Scott R Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 16 Mar. 2007 Location: Gaines, MI Status: Offline Points: 1392	Post Options Post Reply Quote Scott R Report Post Thanks(0) Quote Reply Posted: 31 July 2008 at 1:44pm
	This is off the wall and anybody is welcome to shoot down my theory. Have you checked the voltage coming from the regulator? I just replaced a regulator on a tractor that was sending a very high voltage to the battery all the time. Basically I was cooking the battery, how I found out is after shuting down I could hear poping and crackling coming from the battery. Suppose in this condition its quite possible to get limited amperage from the battery until it cools. Just a theory.
	Michigan Flat Fender Club on Facebook 1949 CJ2A #221621 1965 CJ-5

Turtleherder Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 15 Jan. 2006 Location: Asheboro, NC Status: Offline Points: 303	Post Options Post Reply Quote Turtleherder Report Post Thanks(0) Quote Reply Posted: 02 Aug. 2008 at 12:09am
	Are you 6V positive or negative ground? What gauge wire are you using for bat /starter, bat/ground? Do you have ground straps installed from block to firewall and block to frame? Six volt systems require at least 2 ga for bat/starter/ground. Ground everything.