starter relay

rcrgrl · 11-26-2005, 11:12 AM

hi all, i'm new to this so thanks in advance for your patience! I am having starter problems in my '72 which I believe are the result of a dead starter relay. (I've read the tech articles and tested the ignition switch, starter, battery, ground strap, etc., etc.) For clarification, the relay is an aftermarket "upgrade" right? Based on that assumption, is it better to try and revert back to the no-relay wiring? This was my first thought, but in all honestly I have no idea what the original wiring is - maybe just replace the relay and be done with it? Any thoughts or suggestions? Thanks!

degreeoff1 · 11-26-2005, 05:14 PM

Yes, the relay ( if like mine ) is back under the car by the starter. It SHOULD unplug and IS a lifesaver..........IMHO. Take it out and put in a new kit

Pelican sells em cheap on this page

http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait=N&make=POR&model=9144&section=elchrg&page=1&bookmark=3&part_number=BOS-WR1

RandyLok · 11-29-2005, 03:13 PM

Relays are pretty simple and reliable. Did that turn out to be the real problem? Just curious what you found.

rcrgrl · 11-29-2005, 10:17 PM

the relay was pretty cruddy, but replacing it didn't fix the problem. removing it....and then cleaning the relay board (i think thats the correct name, where the voltage regulator, etc. plug in)... did fix the problem. now, for fun, i'm going to re-install the new starter relay and see if it still works.

rcrgrl · 12-01-2005, 03:37 PM

wow, i am so frustrated! the new relay did notfix the problem as it randomly is not starting again. i'm sure the problem is right in front of my face! i've checked/replaced the ignition switch, hot start relay, relay board, starter, alternator, voltage regulator, battery, & ground cables to battery & transmission. can't find any major draw of power when i turn the ignition to start...so again any suggestions would be sooo appreciated.

RandyLok · 12-01-2005, 03:49 PM

A remote starter switch could be real handy to troubleshoot this.

I made one with parts I had laying around.

Next time it fails, jump 12v from the main starter power terminal to the solenoid terminal and see if it cranks. The results from that little test will narrow things down in a hurry.

rcrgrl · 12-01-2005, 04:15 PM

i'm confused, wouldn't that be the same idea as jumping the starter with a screwdriver? (which it does very nicely)

swl · 12-04-2005, 07:08 AM

Tracking down intermittents is such a PITA. When it fails to start does it fail enough that you can use a meter to track the path? Or is it the sort of thing where one key turn fails and the next succeeds? If you can get some time in fail mode then a volt meter can help. Other than the switch there are only two terminal connections on the way back. You should be able to isolate it by checking for 12 volts coming into the relay board and then leaving the board.

With all that you have replaced there really isn't much left other than the wiring harness and connectors. I suppose you could run a direct wire from the switch to the relay or even the solenoid to test the harness theory. I wouldn't leave it that way though because it would be an undocumented obstacle during engine removal.

914GT · 12-04-2005, 07:48 AM

I've seen starter motors go bad, when one set of windings to the commutator go open circuit. When the motor spins down and lands on the dead winding it won't start up the next time. I would suspect the motor if you've confirmed you're getting a solid 12V on the terminal to the battery and at the solenoid from the ignition switch.

RandyLok · 12-05-2005, 10:14 AM

Quote:

Originally posted by rcrgrl
i'm confused, wouldn't that be the same idea as jumping the starter with a screwdriver? (which it does very nicely)

Yes, it's the same idea. Didn't know you had been doing that.

Intermittent makes it tough, but if it cranks with the screwdriver every time it fails with the key, then you have narrowed the problem down to the circuit between the solenoid and the ignition switch. Most often, this means the ignition switch (not sure how you tested yours) or the seatbelt relay junk under the passenger seat (which should be bypassed by joining the large yellow wire).

rcrgrl · 12-07-2005, 10:32 AM

I've replaced the ignition switch with a new one. also re-installed the new starter relay, with a new ground. went in last night and cleaned out the fuse box, relays, and grounds in general everywhere i could find. unhooked the radio. um, but i didn't think that the seat belt relay was an issue with the '72? anyway, its started 3 consecutive times! will let you know if its truly fixed.

RandyLok · 12-07-2005, 01:31 PM

Um, yeah, no seatbelt relay in '72. Um, was just pointing out the common failure areas, and missed the year before.

The good news is a cracked ignition switch is 99% more likely to have been your problem than the relay. Good luck!

philinjax · 12-07-2005, 04:51 PM

rcrgrl,

It would help us to assist you if you would describe what you mean by "no start". When you turn the key and the engine does't start do you mean that nothing happens, that the engine turns over slowly but doesn't start, the engine turns over smartly and doesn't start or the engine doesn't turn over and you hear a clicking, chattering noise?

Phil

rcrgrl · 12-07-2005, 09:01 PM

sorry - i've been over it so many times in my head that i forgot that detail! it just clicks, the starter doesn't crank at all.

philinjax · 12-08-2005, 06:52 AM

rcrgrl,

First, check out your hot start relay wiring against this drawing.

Phil

rcrgrl · 12-11-2005, 05:38 PM

Thanks, Phil. I checked and the wiring seems fine. I think I'll just be sure to park on hill so I can bump start as needed!

philinjax · 12-11-2005, 06:35 PM

rcrgrl,

Look, I understand you get the engine to start smartly by using a screwdriver to short the solenoid terminal to the battery lead. If this is the case then we know the starter, lead from the + terminal of the battery, the (-) lead from the battery to the chassis, the tranny ground strap to the chassis and the solenoid itself are all good. This means that you are not getting a good 12 Volt signal to the hot start relay (click, click, clatter, clatter, clatter), i.e., there is too much of a voltage drop in the fat yellow wire from the ignition switch and the hot start relay.

I suggest you pull both the 14 pin connector and the 12 pin connector off of the relay board. Spray clean the pins and mating points on the relay board with a contact cleaner and lubricant then reconnect. (Radio Shack has an excellent cleaner-lubricant.) The fat yellow wire from the ignition switch passes through these relay board connectors.

If this doesn't fix the problem, I suggest you remove the hot start relay and return the wiring to the original stock configuration. If the solenoid continues to clatter, this would indicate that the hot start relay would either be defective or have been miswired. I hate to harp on this but, there "ain't anything else".

Good luck at it.

Phil

Jared at Pelican Parts · 09:11 PM

Quote:

Originally posted by rcrgrl
hi all, i'm new to this so thanks in advance for your patience! I am having starter problems in my '72 which I believe are the result of a dead starter relay. (I've read the tech articles and tested the ignition switch, starter, battery, ground strap, etc., etc.) For clarification, the relay is an aftermarket "upgrade" right? Based on that assumption, is it better to try and revert back to the no-relay wiring? This was my first thought, but in all honestly I have no idea what the original wiring is - maybe just replace the relay and be done with it? Any thoughts or suggestions? Thanks!

replace your starter solenoid. This will solve the problem once and for all. you will need to remove the starter, then get rid of the relay.

Years of the solenoid arcing as it makes contact has built up a nice layer of electrically resistant crud on the contacts.

PM me if you need additional info. Done this on many a 914.... rather easy.

philinjax · 12-12-2005, 06:12 AM

If using the screwdriver starting technique, solenoid to the battery wire, works everytime then the solenoid is not the problem.

Phil

Jared at Pelican Parts · 12-12-2005, 06:30 PM

Quote:

Originally posted by philinjax
If using the screwdriver starting technique, solenoid to the battery wire, works everytime then the solenoid is not the problem.

Phil

I beg to differ by experience. Many times I have been able to start my old 914, many VW's, my 911, and SBC Chevys with a screwdriver, when it had a worn out solenoid.

Using the screwdriver bypasses the distance of the wires going to the ignition switch and back. This cuts down the resistance and allows the solenoid to operate, however, the contacts on the solenoid will still have corrosion built up.

The hot start relay is supposed to provide more power to the solenoid to overcome the resistance in the wires. Decreasing the resistance in the wires is a stop gap measure if the solenoid contacts are corroded, however it will eventually need to be replaced.

To fix, remove the starter, then remove the solenoid on top. You'll have to play with it a bit, but it's pretty easy once you understand how the mechanism works. Once you remove the solenoid, you can open it up and look at the contacts inside. They will most likely be corroded. In the case of some of them, you can clean up the contacts with emory paper, and you're good to go.

It's also not a bad idea to run an aux. ground strap from the mounting hole of the strarter to the frame. Also check how much resistance is in the circuit for the key switch, and clean the terminals on the board in the engine compartment. The ignition wire is yellow. I had to replace a section of wire in one 914, but used thicker gauge.