Damn...been working on my 51 merc M1 since Aug. of last year. Already for her big first outing today and things were ok for about 8 blocks. She is stock, flathead, 6v, etc.
Pushed her over to the side of the road, and when i pushed the starter button, it engaged but failed to turn the motor over. No problem before, but all i got was the clunk...then nothing. Each time I pushed the button.
Had to tow it home and after letting it sit, started right up. Ran it for a bit, shut her down...then same thing.
Coil? Condenser?
Any help would be much appreciated.
Thx in advance
Rick

 

Sounds like it could be a coil if it stops after it getshot.

If it runs fine when hot but won't start when hot first thing to check is all battery connections. I had the problem of not starting after getting hot. I pulled every battery cable, from battery to block,battery to solenoid, and solenoid to starter. I wired brushed the stud on the started and replaced all nuts, lock washers and bolt with new. From that point on I have never had a problem starting. Most will suggest upgrading to 12 volt but if all connections are clean you shouldn't have a problem.

 

If your selenoid is hanging up you should be able to test ...when it fails just unbolt the battery side cable to the starter selinoid...this should release the "stuck" condition...and rehook the cable, should start or at least give you a different reaction (if its the selinoid), other than that I agree to recheck all ground points.
good luck with it.
Ed

 

I misread your post the first time. To me it sounds more like a starter problem. If you starter has worn end bushings what will happen is the amature will spin OK when cool but once the engine is warmed up the amature will warm up and expand. There is very little clearance between the amature and fields in the starter and if the bushings are worn they will allow the amature to come in contact and bind. When the starter cools the gap will open.

I would check the cables first.

 

I had this happen in a 49 Ford car with a flathead V8
Water pump seized and the starter wouldnt turn the engine over. After a few tries it started cranking but slow. I heard a squeel, the belt and pulled over and shut it off. I couldnt find anything wrong and tried cranking it over and it just grunted and then started turning but slow.
The gauge wasnt overheating,,, I was close to home and made it back. The belt was loose enough it let the engine run once it started and wasnt smoking the belt.
I scratched my head on it for a while before I figured out the water pump seized.

 

My truck quit when it started to warm up and the coil was shot. They will work when cold, but when they heat up they dump. So if it was just the starter, I'm wondering why it quit in the first place. Maybe you have two problems. Coil and starter. (are we helping yet?).

When it quit did it spit and pop and run for a sec then spit pop and die a little like running out of gas? Maybe a little backfire? That's what mine did with the coil problem - something to do with the oil inside the coil - got a "Flame Thrower" - solid core on those - no oil.

One other question....how is your generator output. Were you possibly just running on the battery and it went dead while you were running - low voltage to the starter? Let it sit and it comes back up a bit? Although it takes lots less current to run the truck than turn the starter - just throwing out ideas.....

J!

 

Well...here goes ...(appreciate the comments so far, but thought of a few things after i posted which might clarify a few things)
-New battery, new battery wires and clamps, new bolts etc.
When"Cold Starting", she turns over and starts with nooooooo problems.
After running (up until the short trip today) and idling, I would shut her off, and upon attempting to start, it would really, really be a slow, slow crank but would eventually start. Sometimes it would be the clunk after pushing the button, which kind of makes me think a dead spot in the starter...but the no turnover thing is weird.
I have the battery charger on it now. Will check and see when i get it running tomorrow that the generator is charging the battery.
I know i have to expect a few bugs so not panicking yet...lol.
One issue at a time. She was sitting around in the previous owner's garage for 18 years.
I do have an extra starter I could get checked, still want to start with the obvious to you guys and gals.
Thx again...hope this helps with more ideas...
Rick

 

dain this sounds oh so familiar ... like a certain 49 in the other drive ...........

 

I suspect it's the starter. The no turn over part is because the armature is sticking to the fields. As I stated above, when the starter gets warm the armature expands and binds up. The clunk sound may be the armature hitting the fields, which are basically big magnets.

 

dainit so much for me sounding wise , bob beat me to it . i reread the post and was thinking and it dawned on me you probably had a bad starter . oh well . good job bob !!!!!!!!!!!!!!

 

I know from experience. I also know if you crank on the starter too long you can melt the solder from the stud and field connection, again, I know this from experience.

 

Ouch I just thought of one more thing....after the other info, that sheds a little more light......Oldgreen51 just touched on it. Is is possible the engine is overheating and the gauge not showing it? Are you sure you have OIL PRESSURE when the engine is running?

I'm not trying to discount the inputs on the bad starter, and the coil could still be a problem, but I'm still not over the part where it was running then quit. Im wondering if the engine is getting too hot and starting to bind up and that's why it quit AND the starter wouldn't turn it (especially after you pushed it and the engine temp had a chance to climb more. When it cools off it will turn freely and start.

Very elementary, but if you just got it going, did you heat it up and cool it off a few times to get the thermostat to open and the coolant in the radiator to flow into the engine - top it off thing?

J!

 

If the coolant is the problem that's not good to run it until it stops. He didn't really make it clear in the first post if the truck just died on him, just that he pushed to the side of the road. On more thing he could try the next time it has this problem is to push start it. When my trucks wouldn't start when warm I could always get them started by pushing them. If it starts when pushed then it's something with the starter.

If you're not sure you have the heads filled with coolant you can vent the air out by loosening the sending units until you get water flowing out.

 

Yep Bob I'm with ya on that! I just wanted to avoid using the words SEIZING UP - ouch!

Good point about the push start. It might also tell you if the engine is bound as well if you throw it into gear and the wheels stay locked!

I might be tempted to do a little more warm up testing in the driveway before another road trip to avoid some possible serious damage.


J!

 

Julie,

You don't get it. You're suppose to take the truck out on the road, at least five miles from home for the initial test drive. That way it's sure to break down. To make it better do it on a Sunday night, that for sure will guarantee the problem will show up. If you stay in your driveway close to where you have all you tools, and some spare parts, it'll probably run like charm. Nothing will make the bugs come out like being away from home. Again, I know from experience.