MrCnos

So I have a 61 dynamic 88. Have done a bunch of work to get it running smoothly, which it does. HOWEVER, it's not the easiest car to start. When I turn the key, I get great cranking sounds, but the car won't start in the fully cranked position. Instead, it prefers to start right as I release the key back to neutral position. Once it has done this a time or two (If i am in and out in a short period) it seems to start a bit easier each time. I just bought a NOS ignition switch off eBay in case that was the problem and have recently had the wiring redone by a reputable mechanic, so I'm not sure where else I should expect the problem to be?? Any thoughts?

MDchanic

It's almost definitely the wire between the Solenoid R terminal and the coil (+) terminal, or else the solenoid itself.

- Eric

Charlie Jones

Don't be too quick to replace the ignition switch. The problem may be in either the starter solenoid or the wire that runs from starter to the coil.
While cranking the starter solenoid supplies battery voltage (12v) directly to the coil to provide a hotter spark when cranking.
When you release the key, power is sent to the coil through a resistance wire which cuts it to about 9 volts to help increase point life .
To check your problem put a test light on the " I " terminal on the cap of the starter solenoid while you have someone attempt to start the engine . You should have voltage. If not replace the solenoid. If you do have voltage then check the wire between the solenoid and the coil .

MDchanic

The problem can't be in the ignition switch. If it were, the starter wouldn't crank.

- Eric

MrCnos

Ohhhhhh, I thought since the key in the ignition was loose perhaps it was not making contact with the switch to bypass the resistor or something, and the quick release was somehow making the connection??? I don't know. I will definitely check the wiring in the morning when I have some light. Thanks for the advice!!

nsnarsk65cutlass

Agreed looking for battery cranking voltage to + side of coil.

billmerbach

Actually I would replace the ignition switch the contacts are more than likely bad ivehad this problem many of times.9 times outta ten it was most definitely the ignition switch

JPMDaddy

Really??? LOL

rocketraider

It can. Seen this on many 61-66 cars. There are cranking contacts and run contacts in that switch. You may be getting power thru the switch to the solenoid which will allow the starter to spin, but the internals may be buggered up to where the "run" contact doesn't allow voltage to the coil to get the engine running.

Look at a wiring diagram and you'll see how this can happen.

m371961

Looking at the diagram I see 12 V to the coil through the solenoid contact, the power for that contact comes direct from the battery. I'm with MD. I have seen the opposite, only runs with ign. switch in start position caused by ign. switch.

MDchanic

You're right and I'm wrong.

I hadn't realized that the early sixties cars are different from the mid-sixties cars (which are different from the late sixties and seventies cars).

The early sixties cars have a separate, dedicated wire from the ignition switch (IGN2, black), which feeds the coil directly while cranking, in addition to the running ignition wire (IGN2, yellow), the starter wire (SOL, purple), the TEMP-light grounding check wire (GROUND, pink), and the accessories circuit wire (ACC, red).

The mid sixties cars do away with the separate IGN2 wire and feed the coil off of the R terminal of the solenoid while cranking, but turn off the regular ignition circuit (IGN, pink) at that time.

The late sixties cars do away with disconnecting the IGN circuit while cranking, so that a bad ignition switch can't cause the vexing "runs only while cranking" problem.

So, yes, it could be your ignition switch, specifically the black wire from the IGN2 terminal.

We regret the error.

- Eric

m371961

Hmm, I looked at the 65 diagram. What year did they go from the Ign 2 wire to the solenoid controlled one?
Well, been wrong before and certainly will be wrong again.
"Once, I thought I was wrong, but I was only mistaken."

MrCnos

So I checked my service manual for the wiring and ignition. I ran wiring from the battery to the coil, started up in a second. Then again from battery to the cable running to the starter solenoid where it begins near the horn relay (picture included). Started up instantly. I can assume all of that wiring is intact. I have to agree that my next concern would be the old-*** ignition switch, but I will be getting that delivered early next week. I'll see how it looks at the switch, wiring and all.

MDchanic

This is a great diagram - it's got some feeling to it.





So far, so good. You've eliminated the entire ignition system, and implicated the current supply, from the battery through the switch, to the coil.



I will admit that this one confuses me.

You jumped a wire between the horn relay junction block terminal, and where on the solenoid?

Or are you saying that you jumped from the battery to the horn relay?

If the latter, then it shouldn't have had an effect, since all of your car's current runs through there, and there's nothing wrong with the rest of your car (unless there is, and you didn't mention it yet).

- Eric

MrCnos

Yeah, I was just making sure the cable going to the solenoid was fine. So may have been unnecessary.

MDchanic

Okay, but what I can't figure out is why doing this would make the car run.

Unless you mean that when you did this, you also jumped a wire to the coil.

- Eric

MrCnos

I'm not really sure. There are other wires on the same bolt which may have indirectly routed to the coil, I know one goes to the ignition switch from there (I'm guessing to connect to the battery) So perhaps I forced a connection there that isn't happening due to the switch being bad?? I am maxing out my mechanical knowledge here...

MDchanic

The big terminal on the horn button is hot all the time, so connecting it to the battery would be redundant, and would not change anything. That's why I'm curious.

When troubleshooting, we try to whittle away all of the things that might be true, and stick with the things we are certain about.

- Eric

MrCnos

Hmmm, well my friendly mobile mechanic was moving wires around and having me crank it so I may be mistaken on where the wires were placed. I guess it was coil to bolt, not bolt to battery.

MDchanic

That'd make sense.

You want to check the output of that IGN2 terminal on the back of the ignition switch (I think it's labeled, but it should have the black wire).
It should be hot when cranking, but not at other times.

- Eric

MrCnos

This is exactly the plan, this tuesday when the new switch comes in. I will keep the thread updated on what we find. THanks for the input, super helpful! The car is so close to being a daily driver (though it never will) in regards to overall reliability, without too much cost as yet.

rocketraider

Don't be surprised if you find some overheating damage on that switch plug. If you're very lucky it won't be melted to where you can't successfully remove it from the switch body.

MrCnos

I realize this is WAAAAY late but it wasn't really the ignition switch. It was just some wiring around the solenoid as mentioned. The switch was replaced anyway, but the carb and starter are still not entirely in tune, so it's better, but not fixed.