healey1968

1) I don't think the jump point is really your problem. I know I'm just adding to the confusion, but an amp meter reading on the fat cable to the starter (or right off the battery) would be really interesting. I bet it's going to show a huge current load going to your starter.

Remember, each time you use the starter, it gets very hot. Therefore if it's already a little hot (after driving like you did in your video) and you use it twice in a row, I bet it's VERY hot. Lends credence to the expansion theory.

2) I think the high running temperature plays into this somehow. I can't think if it's a cause or effect yet...

dcdrechsel

Assuming the battery is good -the symptoms suggest a bad starter motor or the solenoid .Not sure how these were tested .The solenoid could partially work and appear ok until hot and under load .The jumper cable bypass test tend to rule out bad connections .
Haven't looked thru the wiring diagrams but the clutch interlock may have a relay in the circuit that is flaky .

speed rII

This was not what I (or Ahsai) suggested you to test.

Take a nother car, or battery that is freshly charged and use that to jump the car. Like you would do when you have a empty battery in the car.

Do this test from the battery and from the jump point at the engine bay.

If the new battery starts the car in both places, problem is in your charging system.

If it starts from the engine jump point, but not from the battery, it's the cables.

If no start on both places, the problem is the starter.

Simple as that.

Ahsai

Right and I think he still planned to do those tests.

I think he has problems with the battery and/or charging system at least.

In his clip 0:24s cold start, his battery is at only 11v before cranking. You could actually hear the cold start is slower than normal. Hot start at 2:40s shows 11v as well. At 11v, the battery will struggle at cold start and won't have a chance at hot start if his starter is acting up or has more resistance to turn when hot.

His voltmeter reads 14v right after engine is started and seems to remain at 13.5v or higher throughout the drive so I think it's more likely the battery itself is not holding charge. Granted he may also have a problem with the starter especially with the hotter than normal engine.

Shark Attack

I don't go by the dash gauag my meter tells me I have 12.6 with key on at the jump point cold, the crank is the fastest (cold) it has ever been. It has NEVER cranked as fast as it does since I have cleaned up every ground and pos cable connection in the car. I will get back to it tomorrow. Had to take some time off before I beat it to death.

Shark Attack

it was getting heat soaked from the engine running hot due to the drivers side Rad fan not kicking in for stage one.

Jumpered the stage 2 rad relay to kick in when stage one is activated for testing. Drove car will over an hour. Car now starts every time.

Well that was simple

Ahsai

Glad to hear that you get it sorted out. That's an interesting case.

extanker

good that it is fixed and good for the report back

acadian_dad

I'm having same issue - starter getting bogged down and won't start the engine when hot - all voltages are good - starts fine cold.

Sure enough my drivers side radiator fan stage 1 is not coming on - opening up connector X1/1 in the frunk I can measure that the ballast is open but the stage 2 path looks OK.

Now my car is a track-only car with AC removed - wondering if there is any reason not to permanently jumper stage 2 to stage 1 ? This would be a lot cheaper than a replacement ballast resistor ... Any reason why it would be bad to run the fans on high rather than low the bulk of the time ?

As a separate question is it more likely that my engine compartment fan is nixed ? It seems strange to me that a stage 1 radiator fan would make a difference when the car is being driven at speed and as soon as the engine is turned off it would do nothing anyway ... I tend to not let the car idle for long even after a run.

Is there any reason to expect a new or rebuilt starter would be less heat sensitive ?