TR2/3/3A Will Not Start

Been working through some issues with my 1958, TR3A. Started with needing to replace the generator. There is a local shop in San Jose that has been around for awhile and did a nice job. Also replaced the voltage regulator. Prior to this the car would start easily. Easy starting was helped by having a reduction gear starter installed by the previous owner. Background on the car. Purchased about 4 years ago. It had been running really well over the last few years up until now.

What I have done so far with the starting issue:

1). Checked gas. SU Floats have gas. Spark plugs are wet as well when removed and inspected.
2). Removed spark plug and reattached the spark plug wire cap. Had spark plug tip up against the engine block while motor turned over. No spark.
3). Replaced the distributor cap and wires. I have a back up that worked when on the car previously a few years back. Car would not start.
4). Replaced the distributor rotor. Replaced with an unused/new one. Car would not start.
5). Replaced the condenser with a new one. Car still would not start.

I have gone through the Haynes manual regarding the ignition system. Need to retrace what I have done so far. I also need to figure out next steps. Here is what I am considering to do next. Let me know if there are any additional steps I should be taking.

a). Replace the points. I do have a new set.
b). Figure out how to test the coil. I was planning to test by removing the main coil wire where it attaches to the distributor. Then have the tip up against the engine block to see if there is spark when the engine turns over.

I am interested in hearing from others on best way to test the coil. And also any recommendations on figuring out the reason for no spark at the spark plugs and the car not starting.

Thanks

Weird it happened after the generator replacement - did it crank up OK at the autoshop when you picked it up? Try tracing 12V from ignition switch to the points if you didn't already. I know coils can go bad, but I've had several condensers go bad. Jeff

TRopic6 said:

Weird it happened after the generator replacement - did it crank up OK at the autoshop when you picked it up? Try tracing 12V from ignition switch to the points if you didn't already. I know coils can go bad, but I've had several condensers go bad. Jeff

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I installed the rebuilt generator. The business I am referring to did the actual generator rebuild. I have started the tracing based on the information from the Haynes manual going back to the starter solenoid and voltage regulator. Next step is to trace back to the ignition switch. Not a whole lot of room behind the dash so decided to wait until last on testing the ignition switch. Thanks for your suggestion.

I hear ya about the ignition switch. I just spent several hours standing on my head removing the headlight and ignition switches, which had about a half ohm of resistance when there should be 0. I rebuilt both and after cleaning the brass contacts they work great. But placing the short bits of wire between the switches is hard to do with the switch panel in place. I didn't want to undo the choke cable, oil pressure gauge, etc to pull it out, although it probably would have saved time.

I was lucky and the ignition switch got to 0 resistance in the ON position after flushing it through with some CRC. Here is a spare ignition switch I redid after drilling out the hollow rivets. Everything was cleaned, repaired the broken stop plate, and put it back together. The Bakelite is too old to risk riveting it back together so I will use some plastic screws & nuts. Advanced Auto Wire has some great wiring diagrams on their website if you haven't seen them. Jeff

If plugs are wet and not flooded as in to wet one down key switch to coil wire jump coil to battery skip key switch. remover plug wire and check plug wire to block for spark. I had the tab broken on my rotor and it moved as not to match up with dis cap but you changed rotors put the rotor may need a good polish Spark plug wires should jump to ground by 1/4 inch Madflyer

Did you check to see if the post on the points is isolated from the wire to the condenser? There's an insulating spacer that sometimes is the culprit.

Mickey

You say you have replaced or reconditioned the voltage regulator, have you got all the wires back on in the right places, use a test light to see if you have voltage in the white wire on the coil with the ignition on?

Graham

Perhaps put the old regulator back on maybe the new one is defective. Somebody a while back had an open circuit in the regulator.

TRopic6 said:

I hear ya about the ignition switch. I just spent several hours standing on my head removing the headlight and ignition switches, which had about a half ohm of resistance when there should be 0. I rebuilt both and after cleaning the brass contacts they work great. But placing the short bits of wire between the switches is hard to do with the switch panel in place. I didn't want to undo the choke cable, oil pressure gauge, etc to pull it out, although it probably would have saved time.

I was lucky and the ignition switch got to 0 resistance in the ON position after flushing it through with some CRC. Here is a spare ignition switch I redid after drilling out the hollow rivets. Everything was cleaned, repaired the broken stop plate, and put it back together. The Bakelite is too old to risk riveting it back together so I will use some plastic screws & nuts. Advanced Auto Wire has some great wiring diagrams on their website if you haven't seen them. Jeff

View attachment 66815

View attachment 66817

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I appreciate the pictures and detail. Never have taken this one on, but after more testing, if it really is the ignition switch I am now much more confident about trying to clean and reuse existing. Thanks for the info.

Graham H said:

You say you have replaced or reconditioned the voyage regulator, have you got all the wires back on in the right places, use a test light to see if you have voltage in the white wire on the coil with the ignition on?

Graham

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Good idea. I did check the wire connections between the generator and voltage regulator after installing (I recall this involved connector D and F on the voltage regulator). They are good based on measuring resistance. Now need to see about doing the same for the other connections. The Haynes manual suggesting testing current at A and A1 connections. I did this by checking current levels at these points which game to approx 25 amps for each. Funny thing is I have owned and worked on TR's for over 40 years. This is first time I have needed to work through this type of electrical issue.

sp53 said:

Perhaps put the old regulator back on maybe the new one is defective. Somebody a while back had an open circuit in the regulator.

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Good idea. For some reason starting out with the generator light issue, I was convinced the original voltage regulator was bad. Instead it turned out to be the generator. So maybe the old voltage regulator is fine.

Mickey Richaud said:

Did you check to see if the post on the points is isolated from the wire to the condenser? There's an insulating spacer that sometimes is the culprit.

Mickey

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Learned about this a number of years ago. And it took me some time to figure out too! I did check yesterday and looks to be where it should be. I will need to go back and recheck this. I appreciate you bringing this up. My concern is that I missed something when working on this problem yesterday. Will also need to go through the different items again to recheck as well. Thanks for the help.

Madflyer said:

If plugs are wet and not flooded as in to wet one down key switch to coil wire jump coil to battery skip key switch. remover plug wire and check plug wire to block for spark. I had the tab broken on my rotor and it moved as not to match up with dis cap but you changed rotors put the rotor may need a good polish Spark plug wires should jump to ground by 1/4 inch Madflyer

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I did notice the rotor I replaced was not clean and needed polishing on the metal end. Enough so that I thought this could effect connectivity. I thought replacing with a new rotor would work. When I get back to this will trying polishing the original rotor and reinstall. I also want to see about testing the coil. I am thinking this can be done by removing the coil wire on the distributor end, have the coil wire end close to the engine block and try turning the engine over to see if there is spark. Looks like this was your suggestion as well. Best guess right now is that the coil might be a potential issue. Need to see if I have a back up coil or will need to purchase a new one.

I find unbolting the coil from the block PINA difficult--- that screw seems to fight back, so when I find myself where you are at with coils, I take a second coil rap it in a towel set down, swap the leads, and give it a go.
steve

sp53 said:

I find unbolting the coil from the block PINA difficult--- that screw seems to fight back, so when I find myself where you are at with coils, I take a second coil rap it in a towel set down, swap the leads, and give it a go.
steve

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Great idea Steve. Had not thought about this approach.

Mickey Richaud said:

Did you check to see if the post on the points is isolated from the wire to the condenser? There's an insulating spacer that sometimes is the culprit.

Mickey

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Agree & have experienced this. Remember the wires from the condenser & primary from coil must contact the spring to the points and all must be insulated from the spring pivot screw and nut. The spring is in effect a "wire" that goes to the movable point. The fixed point is grounded. Here one can see the two connectors are sandwiched between the nylon "hat" and the spring.

You never quite said this, but we all are assuming that the starter cranks OK; the engine just won't fire. Correct?

I think you need to do some systematic troubleshooting instead of just randomly replacing parts. The most basic test is to see if you have spark at the plugs. If so, you can forget about rotor, points, coil, and all that. If not, work your way back to the coil and see where you are losing it. Check the voltage at the coil, make sure you are getting 12V there. Then you can eliminate problems with voltage supply. Measure the resistance from the points terminal on the distributor to ground, and make sure it changes as you crank. And so on.

If the ignition is OK, next stop is the carbs. Check to make sure you're getting fuel. If you're getting fuel at the carbs and spark at the plugs, the sucker has to run!

I'm also assuming that you haven't made any adjustments, removed the distributor, or anything like that. If so, it adds a whole new level of things to think about.

Oh, and one more thing: you probably can't measure the difference between zero ohms and a few tenths with most ohmmeters. They usually have an offset of a few tenths of an ohm (i.e., read a few tenths when the probes are connected together) and the way you connect the probes can affect the readings by a few tenths, too.

Not to over kill the obvious or anything like that. If the car ran fine before, I would suggest not getting too far away from something you replaced very recently.

sp53 is right if you changed the control box and din't get the wires back in the same place you will not have any power in the ignition circuit.

Graham

steveg said:

Agree & have experienced this. Remember the wires from the condenser & primary from coil must contact the spring to the points and all must be insulated from the spring pivot screw and nut. The spring is in effect a "wire" that goes to the movable point. The fixed point is grounded. Here one can see the two connectors are sandwiched between the nylon "hat" and the spring.

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First off, great explanation and photo. I also had the experience of doing this incorrectly in the past. When I installed the new condenser yesterday, I used the approach you so well covered in your description. I will go back and recheck to make sure this was done correctly.