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Old Gal - Still won't start

Started by racertb, April 11, 2014, 10:13:11 PM

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racertb

Here are latest observations and symptoms:

Car turns over, distributor turns, etc.  Tried two sets of points and condensers.

First set, car turns over, but sounds like starter getting hung up every few revolutions.  Take off distributor cap, car turns over and no weird starter hang up issue.  Intermittent spark of coil wire jumping to head bolt when checking for spark.

Second set of points/condenser, no starter hang up sound every few revs, engine turns over fine, but no spark from coil wire.

I've tried setting both point sets at both .18 and .20 and it doesn't seem to matter.  At this point, not concerned about timing until I get consistent spark. 

Running out of ideas, but I'm thinking its got to be electrical and a hopefully simple fix.

Thoughts??  Going crazy here. 


racertb

I'm wondering if the small wire going to the side of the distributor that attaches next to the condenser wire is not insulated correctly and grounding out affecting the points and causing the no spark condition?

How should that be attached so this isn't an issue?  Anyone ever deal with this?


imoore

If the points are funtioning properly the amp meter should fluctuate when cranking. This means current is flowing through primary circuit and points are opening and closing.

Now a way to test the points is with a test light. So what u do is put the clamp on a good metal connection then put the tester on the distributor connection. When the point are closed the light will be off. When open the light should glow. If u can do this with cranking the engine to make sure it is a continued on-off flash. If the light is allows on it means the distributor or points are not earthed. If the light is allways off it means your have a short to ground at the points or terminal connection.
I would also make sure the HT side of the coil is either conneced to ground or to a spare spark plug. This will stop the coil from burning out.
This is also a good method to set your ignition timing. Called static timing.
The spark from my 6v ignition will jump a good 30mm

I hope i have explained it correctly. It is something i just do and don't think about.
Ian
1928 Q tourer (Holden bodied)
Several vintage stationary engine

Old Man

#3
"starter motor getting hung up every few revolutions" This could be be kick back from the firing taking place too far before top dead center (TDC). So this could point to the timing being way out. Also account for the "back firing" out the intake.
   Trying to make sure you have a good spark is OK but if it's way off the correct timing point it will be useless. When testing for spark in open air,I have noticed in the past that I seem to be missing sparks also. This seems to be normal but I have no explanation for it. I only ever watched to see if I had spark across a spark plug ,clamped to the cylinder head, and left it at that. But in any case if the distributor is turning, a spark would happen every time the points open and close, you just wouldn't know if the spark is on time or not.
  I keep a can of ether around for troubleshooting this kind of problem. A spray down the throat of the carb will make any engine run at least for a few revs. If you have never used the stuff before BE CAREFUL. It's explosive. If you have a remote starter cable and are around the carb when the ether fires way before TDC,you can get a cheap brush cut. But the ether takes the fuel out of the equation. If you get a stable engine for a few seconds until the ether burns off, then you know it's fuel. If you can't even fire the ether then it's spark. If the engine fires with the ether,you can also pour A SMALL AMOUNT of gasoline down the carb along with a snort of ether and see if the engine runs on that. With the added gas down the carb the engine will run for several seconds. (This is a good way to get a hesitant engine that's been stored for a while to start and draw gasoline up from the gas tank. I do it all the time. But BE CAREFUL and always have a dry chemical fire extinquisher handy. A charged garden hose is OK but it won't put out spilled gasoline. The gas will float on the water and continue to burn. I've never had a problem as I was a trained firefighter for 4 years as a young man and have great respect for how people burn up things. You'd be amazed.)
  Somewhere along the line it should occur to you what has gone wrong. A further point on the gasoline. Most people do not know you actually do not need a carb on the manifold for an engine to start and run. All other things being right, a small amount of gasoline poured down the open intake manifold will fire and run for a few secionds. However be careful as the engine will try to run at full throttle. But I put this in to show that gasoline feed is the easiest to troubleshoot.               

chetbrz

Racertb,

Ian & Old Man have given you some good advice.  Based on your statements in both emails here is my take.
Your statement "felt a slight loss of power then some misfiring and then a few loud bangs/backfire, but not from all from the exhaust."  Based on other statements this leads me to believe that your timing had changed dramatically and was shifting from before and after TDC.  Many things can cause these symptoms but the advice to check the distributor time gears seemed real good to me.

Your next statement "Tried to restart several times, finally started and ran for a few seconds then shut off again.  Some more backfire."  Backfiring through the exhaust is the plug firing with the exhaust valve open and likewise backfire through the carb is the plug firing with the intake valve open. 

When your engine is cranking and appears to slow instead of start you are firing the plug to much in advance of TDC.
In these combined instances I would suspect a catastrophic time issue which could be timing chain or distributor.  In the case of our old motors the distributor timing gears should be checked.  (As Old Man Mentioned)

The other issues with poor point timing or a shorted distributor coil may have been caused by the trouble shooting process.  Ian troubleshooting process is a good one to follow.

My 2 cents
http://www.1948Plymouth.info           Web Master - Forum Administrator - AACA member

racertb

Update.   I can open and close the points rapidly to assimilate the distributor turning like the car is running.  I am now getting spark consistently from the coil wire to a head bolt (easy to observe).

The issues seem to be I have to open the points REALLY wide (rapid manner described above) to get the spark to fire from the coil wire.  By wide I'm talking 1/8" wide.  But, I am getting spark so I'm assuming the coil is good.

The other thing I noticed with the points is that it also looks like the spring/bend (curved part) is sparking/shorting against the inside wall of the distributor housing.

I believe this is the issue and because I only get the consistent spark when opening the points really wide is because its pulling the spring/arm away from the inside wall.

I've got other things to do today, so will focus more on this later.  Anyone ever deal with something like this before?

I hope I'm on the right track here and am convinced this is a simple electrical issue.

Thoughts???

racertb

Thanks for the replies, but see my update above to see if that changes anything.

Also, fuel feed is not an issue and carb is loaded with fuel, as it probably flooded last night.  This is because the car has an electric fuel pump and was not too concerned last night since I was only checking for spark.  However, this morning I disconnected the lead to the pump so I could continue checking for spark (see update above) without the fuel pump running when I have the key on.

You guys are a great deal of help and more knowledgeable than me, and I think it is timing with some points shorting out which could be what caused the initial problem.  I hope the above further narrows down the diagnosis.

I once had an old Ford Torino that started cutting in and out and found out the hard way that it was a loose negative side coil wire that was not properly connected/secured.  That major running issue was a simple electrical connection.

I hope this Plymouth issue is a simple issue to fix as well.  Before I did my major tune up, everything had run fine for many years.

chetbrz

racertb,

All you can do now is fix the things that you can see which are obviously a problem than go from there.  As soon as the points open the ckt should fire.  The point gap only needs to be open long enough to allow the coil to discharge fully and to ensure that the points stay closed long enough to recharge the coil.  The differences between .016 and .018 are functionally negligible.

Chet...
http://www.1948Plymouth.info           Web Master - Forum Administrator - AACA member

imoore

My dustributor now that you mentioned the points spring did have a piece of insulating paper between the spring and housing.
A coil should fire evertime the points break open  if they don't it would obviously cause a missfire. All it takes is a very fine hair gap. Not even noticeable. For a spark to occur. All the points gap does is to charge and disscharge the coil for the best possible spark the next time round. 

Also back to setting the timing make sure when u are setting its static timing (engine off) that you remove all backlash from the distributor. By turning the shaft towards the stopper not against the advance mechanism. This will remove any slack in the gears ect. You also need to make sure you only rotate the engine clockwise. If you do go backwards go past the point you want to set it,  then bring it forwards again. This will remove any slack in the cam shaft gears.
1928 Q tourer (Holden bodied)
Several vintage stationary engine

frankp

Ian,  You are correct about the paper or insulating material between the body and the spring.  I checked a spare and it is there.  frank
frank p

racertb

I've never static timed before, but it doesn't sound complicated, however I have a few questions.

Are there visible timing marks on these cars that should be lined up or on the gears themself?  I don't plan on taking the timing gear cover off.

The Instruction Book mentions making sure #4 cylinder is TDC and everything else I see mentions #1 cylinder

Whichever one it is, how do you verify?  The way the pistons are offset from where the plug holes are, a tool or whatever won't exactly work to check.  Should the exhaust stroke air blowing out be used to find tdc?

Hopefully I'm not over thinking this too much,  just trying to verify how off the timing is.

frankp

There are no timing marks visible.  There are marks on the camshaft and crankshaft gear to synchronize the pistons and valves, not the distributor.

#4 piston is nearest the firewall.  On the head there is a screw that allows access to the top of #4.  I put a coat hanger wire to determine TDC (top dead center).  The book says #4 should be going up on the exhaust stroke and stopped .050" before TDC.

Now the distributor is set to fire #1 plug.

My Sixth Edition Instruction Book gives more details on this set-up, page 40.  Pg 39 - 40 gives trouble shooting methods.
frank p

racertb

Thanks Frank!  I never knew about the access screw.  This makes sense with the manual.  I'm not sure what edition manual I have... I'm first going to fix my points.  I looked at them a few minutes ago and the breaker arm is against the inner wall on the distributor.

frankp

Glad to help.  A note on that insulation strip.  On my spare, it has slipped downward and is not between the spring and the body the way it should be.  As I think about it, seems the last time I put in points, care had to be taken to get this correct.  It tended to move as the fastening nut was tightened.  You'll get it figured out.
frank p

imoore

Sorry frank but the 28 engine does not have that access hole. The way i do it is by removing cyl1 plug. Put your finger over the hole and rotate engine over untill compression is felt. Then With a torch look at top of piston untill it is at the top.
Crankshaft to piston orientation is cyls 1and 4 being pairs and 2 and 3 being pairs
By pairs i mean both will be at the top or bottom at same time just on different stroke.  As you can see the firing order is 1,3,4,2. You will notice that only one of the pairs will fire at a time.

A 6cyl as pairs of 1 and 6, 2 and 5, 3 and 4. With a firing order of 153624. 
A little off track but give u an idea

Ian
1928 Q tourer (Holden bodied)
Several vintage stationary engine