MY 51 WON'T CRANK VERY FAST

[Plymouthy Adams]

this is true, it could have been checked, it could have just as easily been tossed components that are also defective in the very bid to Easter Egg the system with new components.  Just because it is new does not mean there could not be a manufacturing error.   Remember you want to read the cable and connections...that means no direct probe contact to the center of battery posts and in turn read the centers of connecting posts down stream on components.  By not reading the post but a part of the clamp you will test the connection of clamp and battery, by reading the center of connection posts you are testing the contact patch of the connector and component.  Do read a few articles on voltage drop testing, each are written by different folks where often one will explain it a bit clearer than the other....you need to be grounded in the theory as they say to perform and interpret your findings.  Good luck, just remember if you find all good cables, solenoids etc.  its a good thing and now officially ruled out as questionable.  As you have the repair manual and should you pull the starter yet again and do a tear down...follow the testing procedures....it will walk  you through the process.  If all else fails, get a stand up cutout of Dr. Lucas with a roll of electrical tape in his hand and place in front of the car....intimidation often goes a long way...

Edited November 19, 2018 by Plymouthy Adams

[Raindance654]

4 hours ago, Don Coatney said:

Remember three things are required for an engine to run. Compression, fuel, and spark delivered at the correct time. What one is missing? I have seen these engines start at a very slow cranking speed as long as the 3 aforementioned things are in place. With the air cleaner removed using a flashlight can you see a good squirt of fuel in the base of the carburetor when you pump the throttle? Have you done a compression test? Have you done a static timing procedure? 

 

Given the remarkable simplicity of the cars and boiling it down to those three things, you wouldn't think there could be such a problem, would you.........??

Of the three, I'd say that I am kinda missing the fuel side of the equation. Although there is plenty of fuel in the carbs and the booster pumps seem to work just fine and give a good jet of fuel when the throttle is opened.

No matter how much fuel I tip down the carbs the plugs remain prety much bone dry. so my feeling is that I'm not geting fuel/air mix down to the cylinders.

Even under cranking, I'm getting a pretty decent spark and on the occasion that I got three buddies to push start the car down the street, it started quite easily and ran sweetly enough, so even though I didn't physically check the timing at that point, I have to think that the ignition and timing must be in the ballpark.  

[Raindance654]

30 minutes ago, Plymouthy Adams said:

this is true, it could have been checked, it could have just as easily been tossed components that are also defective in the very bid to Easter Egg the system with new components.  Just because it is new does not mean there could not be a manufacturing error.   Remember you want to read the cable and connections...that means no direct probe contact to the center of battery posts and in turn read the centers of connecting posts down stream on components.  By not reading the post but a part of the clamp you will test the connection of clamp and battery, by reading the center of connection posts you are testing the contact patch of the connector and component.  Do read a few articles on voltage drop testing, each are written by different folks where often one will explain it a bit clearer than the other....you need to be grounded in the theory as they say to perform and interpret your findings.  Good luck, just remember if you find all good cables, solenoids etc.  its a good thing and now officially ruled out as questionable.  As you have the repair manual and should you pull the starter yet again and do a tear down...follow the testing procedures....it will walk  you through the process.  If all else fails, get a stand up cutout of Dr. Lucas with a roll of electrical tape in his hand and place in front of the car....intimidation often goes a long way...

I like the idea of intimidating my Plymoth into co-operating.

In the meantime, I'll do some homework on voltage drop testing and I'll get the starter motor off once again for some more in depth testing and checking. I've learned the hard way in the past that new does not necessarily mean defect free, so I will be checking ALL components very thoroughly, if only as you say, to eliminate them as questionable.

[austinsailor]

My 48 B1B had similar problems, just very slow cranking. I’d checked everything, including the guts of the starter. Cleaned the armature, brushes bearings and all. Cleaned connections. 

 

One day I got particularly fed up and just pulled the starter off another truck I had and presto - all was good, cranked very fast.

 

might save yourself a lot of headaches if you just buy, borrow or steal another starter.

[Raindance654]

9 minutes ago, austinsailor said:

My 48 B1B had similar problems, just very slow cranking. I’d checked everything, including the guts of the starter. Cleaned the armature, brushes bearings and all. Cleaned connections. 

 

One day I got particularly fed up and just pulled the starter off another truck I had and presto - all was good, cranked very fast.

 

might save yourself a lot of headaches if you just buy, borrow or steal another starter.

That's a great idea..........but as I'm in England these cars are quite scarce. Although admittedly I've only had my Plymouth for a few days, I'm not aware of any of these or similar cars anywhere near me............................ahh the joys............

[Raindance654]

UPDATE. I just did another amp draw test when I was sure the battery was fully charged. The reading was approx 280 amps but peaked at just over 300 amps. To my mind this is WAY over what it should be drawing. My conclusion is that in spite of the starter being apparently in good shape, something is amiss inside............possibly a short in the windings. Before I spring for an eBay special starter could there be any other possible causes for such a high draw.............?

[jeffsunzeri]

Properly testing a starter requires not only a visual inspection, which you've already accomplished, but the field coils and the armature should also be tested electronically.

The most difficult to bench test is the armature. You use a growler to test the armature for shorts, and generally a good ohmmeter can be used to test the field coils.

 

[kencombs]

4 hours ago, Raindance654 said:

UPDATE. I just did another amp draw test when I was sure the battery was fully charged. The reading was approx 280 amps but peaked at just over 300 amps. To my mind this is WAY over what it should be drawing. My conclusion is that in spite of the starter being apparently in good shape, something is amiss inside............possibly a short in the windings. Before I spring for an eBay special starter could there be any other possible causes for such a high draw.............?

don't have my  book handy. but that sounds like about normal at 6v..

[soth122003]

Hey Rain,

Just looked in the book and the amp draw is listed at about 335 amps for your year starter.  You said you tested the battery. Did you load test it with a load meter? I just replaced my battery due to a lack of ass for the battery. It would barley turn the engine and load test showed it was  good but weak. 

 

Joe Lee

 

[Raindance654]

3 hours ago, jeffsunzeri said:

Properly testing a starter requires not only a visual inspection, which you've already accomplished, but the field coils and the armature should also be tested electronically.

The most difficult to bench test is the armature. You use a growler to test the armature for shorts, and generally a good ohmmeter can be used to test the field coils.

 

Whilst the starter is off, I'll get it checked properly......but sounds as though my "good" battery could be weak............

[Raindance654]

3 hours ago, kencombs said:

don't have my  book handy. but that sounds like about normal at 6v..

Ok......so my starter might not be shot after all then...............

[Raindance654]

41 minutes ago, soth122003 said:

Hey Rain,

Just looked in the book and the amp draw is listed at about 335 amps for your year starter.  You said you tested the battery. Did you load test it with a load meter? I just replaced my battery due to a lack of ass for the battery. It would barley turn the engine and load test showed it was  good but weak. 

 

Joe Lee

 

I did drop test (load test)the battery after a full charge with the correct apparatus and it showed very little voltage drop but I have had batteries which test ok under a load test but fail to crank satisfactorily...............perhaps the battery is to blame after all............!!!

[9 foot box]

   Thank You for the reply, Raindance. Being that you are new here, at the top of this page is a technical tab, it's a good read, for everyone.

[Raindance654]

12 hours ago, 9 foot box said:

   Thank You for the reply, Raindance. Being that you are new here, at the top of this page is a technical tab, it's a good read, for everyone.

Thanks for that. I did click the tech tab......and found thousands of threads. The sheer number struck a little torror into me as I'm not sure how I would have found what I was looking for...........lol

[Don Coatney]

Have you tried using jumper cables and a 12 volt battery?

[kencombs]

I don't know if it is possible on this model starter but:  Some cases can be used for both 12 and 6 v field coils.  Since yours seems to have been worked on a lot before you got it, is is possible that it has the wrong set of coils?  Use an ohmmeter to measure the field resistance, and compare to the specs.

[JBNeal]

I had the slow starter on my '48, struggled with it for years...eventually I put a torque wrench on the pulley crankshaft nut to turn it and found that it required over 100 ft-lbs...by comparison, my '49 that ran great required only 40 ft-lbs...considering a problem that I saw when I put the engine together during my ignorant youth, I think I have a spun connecting rod bearing that is binding the crankshaft...so that's on the to-do list

[Tom Skinner]

Get Betsy a Flame Thrower Starter Coil.

Worth every Penny. Static Time her, then Dynamic Time Her. Bang. She will start like a Gun Shot every time

[Los_Control]

6 hours ago, JBNeal said:

I think I have a spun connecting rod bearing that is binding the crankshaft...so that's on the to-do list

You may have a good point there, we all pointing fingers at the starter and it could be something else.

 

Recent thread in another forum, guy put together a fresh 327 and it was to tight for the starter to turn it over. Everyone thought 45# torque to turn the motor was average.

Think he was around 100# torque. .... Maybe he should have installed a 6 volt starter 

He had to pull the motor and then started swapping rod caps around until it turned over as should.

Not the correct fix but he liked it.

 

Putting a torque wrench on the op crank may give more info.

[Ricky Luke]

2 hours ago, Los_Control said:

You may have a good point there, we all pointing fingers at the starter and it could be something else.

 

Recent thread in another forum, guy put together a fresh 327 and it was to tight for the starter to turn it over. Everyone thought 45# torque to turn the motor was average.

Think he was around 100# torque. .... Maybe he should have installed a 6 volt starter 

He had to pull the motor and then started swapping rod caps around until it turned over as should.

Not the correct fix but he liked it.

 

Putting a torque wrench on the op crank may give more info.

 

Actually, try just removing all the plugs. It should turn over easily by the fan.

 

Rick

[P15-D24]

Check the obvious first.

What is your battery voltage fully charged and after you try starting?

Run a capacity load test with a proper battery tester and report the results. (I'm sure you can find a garage that has the correct testing equipment.) I'm betting a tired, slowly dying battery.

Also check the specific gravity of the battery acid. 

With these three pieces of data you should have a good idea as to your battery condition. 

Report what is found. 

 

[MackTheFinger]

2 hours ago, Los_Control said:

 

He had to pull the motor and then started swapping rod caps around until it turned over as should.

 

 

I hope there's a pool on how long that's gonna last.. 

[Los_Control]

11 minutes ago, MackTheFinger said:

 

I hope there's a pool on how long that's gonna last.. 

Yeah he swears he had them marked and installed correctly, just the last 2 when tightened down put the crank in a bind. He swapped those and then only one caused a bind, then he swapped it with another and no more bind.

A pool would be a good response to the thread .... I wonder if any pool going on my build thread yet  

[MackTheFinger]

1 hour ago, Los_Control said:

he swears he had them marked and installed correctly,  just the last 2 when tightened down put the crank in a bind.

 

 

I like to get rods resized so they all match. Maybe it's just me..

 

1 hour ago, Los_Control said:

I wonder if any pool going on my build thread yet  

 

Well, me and my big mouth. You weren't supposed to figure that out!!  ?

Edited November 22, 2018 by MackTheFinger

[Los_Control]

11 minutes ago, MackTheFinger said:

I like to get rods resized so they all match. Maybe it's just me..

In fairness to the guy in that thread, claims all was done by a qualified machine shop, including line bore and they ordered the bearings etc to go with the engine.

The owner put it together and ran into this issue.

 

The engine in this thread has obviously had some work done to it, and looks very nice to me.

Just turning it over by hand should tell a lot. My engine I can hold a beer in one hand and turn the fan blade/engine with the other, it turns very easy and a easy life for the starter.