I recently was working on a 74 1.8 completely stock. I replaced the ignition switch and turn signal switch. All seemed to work fine when the guy picked the car up. Several days later he reported starting issues. turn key nothing happens. However the issue was intermittent and he continued to drive the car. The guy called today and said that if he puts his foot on the brake the car starts every time. Is this the case for 74 and later models.

I just recently have run into a similar sounding issue. at first it seemed to be only when hot (run a while on the freeway)but just yesterday it wouldn't crank in the morning, I've taken to keeping my jumper switch with me just in case, but then fired right up later that afternoon. Hadn't tried the brake but since I never have it didn't occur to me to try.

I was thinking either a starter relay or something to do with that seatbelt interlock thing. either way it seems temp is not part of the issue.

Always cranks right over when jumped at the starter.

This is something I'll be trying to trace down tomorrow if the condition repeats for me.

I'll post back with what, if anything, I find.

Do a search on this site for "the dreaded hot start problem"

I just searched for hot start issues but only came up with no start not no crank. mine will always start it just won't always crank over from the key.

First time sucked lying in a parkinglot trying to jump the starter with a clip I snapped off a pen. now I carry my jumper switch just in case.

Is this what you are refering to or where you thinking cranks but won't fire?

http://www.914world.com/bbs2/lofiversion/i...php?t11814.html

I'm not sure how pumping on the brakes has anything to do with the starting condition. First thing first, jump out the seatbelt interlock circuit, if you haven't done so already.

Thank you for the link however, It's not the starter. I have voltage coming out of the ignition switch but no voltage at the starter solenoid. something is happening between solenoid & ignition switch. It is very intermittent.

I'll chase it down, it's what I do for a living, and post back what turns out to be the culprit.

More than likely the condition is exacerbated by temp but not wholly due to temp as it has now done it stone cold.

Anyway, thanks again for the link but I don't wish to further jack the OPs thread.

This sounds like some wiring issue between the switch and the starter. Many times when moving the old wires to change something, a connector can be jarred to the point where the conductor no longer makes contact all the time.

R&R (remove and replug) all connectors between the key and the starter. Check voltages as you make your way from the key to the starter. It's only one wire to follow. Your issue lies in the wires/connectors.

I just finished tracing down the problem with mine. Every now and then it would not start. No click, nothing. What I found is that the cam on the ignition cylinder wears out so it does not turn the plastic ignition part on the switch enough to start the car. Removed the cylinder and carefully ground it with a dremel, now it starts 100%.

Yep. Fuel pump runs but starter won't turn over. First, I would bypass the seat belt warning mechanism under the pass seat. IIRC, the Bosch solenoid requires 9.6v to close. After traveling thru a 40 yr old overworked ignition switch, thru the seat belt relay and several spade conn's your lucky to get that kind of voltage back there when hot. The Ford solenoid requires < 4v to close.

I fixed the same problem about a year ago, but I thought the pushing surface of the cam would need to be built up in order to push a little farther. I ended up rotating the electrical switch backwards to take up the slack that had developed.
http://www.914world.com/bbs2/index.php?sho...Ignition+switch

What did you grind down?

This is just a theory, but might explain why putting the foot on the brake affects the starting. If it's a 74 and still has the seat sensor switches, the drivers side switch may be flaky and the extra pressure of pushing down on the brake pedal may be letting the switch contact. One solution would be to bypass the seat belt interlock relay. If already bypassed then problem probably is something intermittent with the ignition switch.

Ok, got mine figured out & fixed. The starter solenoid just wants more amps than are making from the bat to the ignition & back to the starter.

I had removed & cleaned all my grounds, all of them! Hiding all over the damn place

Checked for voltage drop to the ignition switch & back at the solenoid. The solenoid from time to time wants more amps than that circuit will give it for size & length.

So I added a relay. Put it right next to the starter. About six inches of heavy gauge wire from the main starter bat+ lug & again back to the solenoid. ran the ground to the solenoid mounting screw & energize it with the original solenoid wire.

It has cranked over much better at all times now & happy to report Zero no-crank issues.

Took far longer to diag than to repair.

To sum up. if you have a random no-crank pull the solenoid wire & see if it will light up a good test light. if it will then add a relay & call it fixed. If not you have my sympathy, it's not a fun circuit to trace.

Upside I learned how to rebuild my underhood relay block. now my voltage always stays above 12.

WOW! I just noticed this the other day on my car (a '74)!!! I have a hi-torq starter and a hot start relay installed and seat belt logic system bypassed.

It will start no problem every now and then(w/o brake). Other times it will just click when i try to start it. Just yesterday I noticed that if I do things in this order, it will fire up every time:

1) Turn key to "on" position.
2) Depress brake pedal.
3) Turn key to "start" position to crank car.

Any variance of that ritual, there is a 50/50 chance it will start.