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 Posted: 11-15-2019 08:52 pm
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DonBurns
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Has anyone experienced the issue below and have any ideas? I've kind of stepped away from the project for a few months in frustration.

I have long experienced what I think is kind of an odd issue. When I turn the key, there is usually a delay before the engine cranks of a second or so, sometimes longer, sometimes no delay. But for a long time it had always started, so I filed it away as a minor concern - but of course it's an old Brit sports car so there are are always concerns ;).

I wondered early on if the issue could be a starter motor or solenoid about to go bad, but eliminated this by connecting my multimeter to the solenoid, and determined that the delay actually meant no juice to the solenoid for that 1 -2 seconds, not a delay in the solenoid or starter reacting. I checked all of the connections from the ignition key to the solenoid, and everything seems good (new main and engine compartment harnesses.)

Three months ago I decided to chance a longer trip, and of course the car wouldn't start at all for an hour. Tried it again and then it started, but I lost all confidence in driving further than I wanted to tow it, so stepped away for awhile.

I'm pretty sure the only point left that could be the cause is the switch on the left side of the steering column that is turned by the ignition key. I have that out and thought to dissemble and inspect / clean the contacts. It has a pretty heavy metal casing and is mechanically crimped together. I'm a little nervous about trying to take it apart.

Any thoughts about my being on the right track here? Is this part serviceable / replaceable? There is clearly a strong spring inside.

Thanks

Attachment: Ign Switch2.jpg (Downloaded 89 times)

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 Posted: 11-15-2019 11:23 pm
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Frank Schwartz
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It could easily be the switch contacts...but on some cars it is merely dirty plug components..often plugging and unplugging it a couple of times sort of cleans the contacts up and you have ignition.
Frank

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 Posted: 11-16-2019 02:32 am
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CDA951
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Hi Don,

We had ignition switch issues with our '74 and managed to get a good used one from Bruce Madden/RedRacer. I would certainly try to locate a good used one if you can.

That said, it would be prudent to wire up relays for the both the starter solenoid circuit and ignition "ON" circuits of the ignition switch. This preserves the contacts because they only carry the low current of the relay coil rather than the main load of the circuit. For our '81 Alfa GTV6 (which also has an unobtanium ignition switch), I ended up wiring in a separate relay for each of the ignition switch circuits---starter, ignition on, and ballast resistor bypass circuit!

Last edited on 11-16-2019 02:36 am by CDA951

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 Posted: 11-16-2019 02:34 am
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Tim Murphy
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I had a turn ignition, no juice going to starter, etc problem that was solved by replacing the ignition switch (the part you pictured) with a used one I had on a steering column I had previously purchased. Delta shows it as available in their online catalogue. I have also wondered if an MGB or other Brit car steering lock and switch assembly could be modified to work in the JH. https://mossmotors.com/steering-lock-switch-assembly-aftermarket-replacement

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 Posted: 11-16-2019 04:36 am
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Tom Bradley
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I agree with Frank. This sort of thing has happened to me several times over the years. It could be the switch, but before messing with it, check all the connections for cleanliness and a tight fit. The connection to the starter solenoid itself is a prime candidate.

If that does not help, then the ignition switch is most likely the problem. It does get dirty and corroded inside and cleaning up the contacts with fine sandpaper (like around 800 grit) or steel wool. I replaced my switch with an electronic switch many years ago, but I remember that the way to take the original switch apart was not at all obvious. I will look to see if I can find my old one and try to remember how it was done. As I recall, it was also not obvious how it all went back together so, if you are going to take it apart, be sure to have a camera handy to get pics of how the various parts went together. Also be careful not to lose the ball bearing(s) inside: they seem to like to disappear underneath any available object.

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 Posted: 11-16-2019 01:25 pm
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Brett Gibson JH5 20497
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Try running a new wire to the starter, you just might have a broken one that is making intermittent contact. just run it out the door and over, if it does the trick then you can make it look pretty later.
Brett.

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 Posted: 11-16-2019 01:46 pm
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DonBurns
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Thanks for the replies. I did contact Delta and they have not had one (used) for awhile, but have in the past sent them out for rebuild. They will let me know Monday. I like the idea of using a relay once this is fixed one way or another. I have added relays for any additions (aux fan / pre oil / O2 meter). I'll also ask Moss about the new ones they have there. There is one called Lucus Brand Replacement

https://mossmotors.com/steering-lock-switch-assembly-lucas-brand-replacement

which looks tantalizingly similar to the JH original. Not the collar, but I wonder if the lock and switch would transfer? Seems like even if they had to make a unique column collar to get the angle right, they would still have used the switch from another car.

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 Posted: 11-16-2019 04:58 pm
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Frank Schwartz
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Sure looks like the same switch to me...maybe one should buy it and see...I think Moss would accept a return if it did not fit...

Frank

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 Posted: 11-24-2019 12:37 am
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redracer
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Okay, fellow "Jensenites"; J.D. Damon (J.D.s British Cars, Nashville) was kind enough to send me an MGB ignition lock for testing, and the results are not promising.
Although the lock is EXACTLY the same diameter as ours, the large hole for the attachment is at 90 degrees to the shaft column, whereas our J-H's is at 18 degrees off!(and therefore will not fit for the ignition key, unless you were to totally remove or modify the "surround").
I was hoping that the electric portion could work, but again it has a different "input" from the keyed shaft and the attachment won't work(unless major modification is performed).
I did note that our ignition lock DOES have a threaded hole underneath for a "different" type of electric attachment(maybe Austin Marina??), so our lock is not unique to our car.(maybe someone could contact the U.K. JOC for help?)
Sorry to be the bearing of "bad tidings" but we still have some good electric switches to part out.
bruce

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 Posted: 08-10-2020 10:31 pm
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redracer
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Don: shuld have replied to this last year--sorry.
The usual reason for the "DELAY" was the logic box with the 12 wires in it(on the side wall where your left knee would be). To bypass this, one would short out #11 with #12; just cut one or the pother and wire together).
Most all the cars I have seen have had this done, but maybe yours is still intact.
again, sorry for not responding directly to this last year. bruce

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 Posted: 08-12-2020 09:03 pm
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DonBurns
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Redracer-

One wire is cut and capped. But not #11 or #12. The cut wire is #4 purple.

Just to be clear, it doesn't matter which wire is cut, 11 or 12? And by shorting, let's say I cut #12. So then strip some insulation from wire 11 and solder #12 to it? The wire from the logic box or from the logic box or the end that had gone towards the logic box?

I've always wondered what the wiring in the logic box was. Is there a schematic showing routing inside the thing?

Thanks

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 Posted: 08-12-2020 09:47 pm
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redracer
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#4, purple, is the constant power(#3/bottom fuse) that "buzzes" you if door is open, the seat belt is not latched(the "LOGIC" box that won't let you start the car), and to let you know if you passed NIgel's Beer Pub for your daily pints!
Yes, cut either one and wrap & solder it to the other(#11 )

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 Posted: 08-14-2020 06:06 pm
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DonBurns
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waiting for battery to charge, but this looks right? The new wiring harness does not have the numbers on the connector, so spent some time tracing wires. Also the newest wiring diagram I got from Delta does not show the 12 wire connector at all!

Attachment: Wire 11-12.jpg (Downloaded 10 times)

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 Posted: 08-14-2020 06:26 pm
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redracer
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Don: from your pic, I believe you wired the correct white-with -red strip(#11) to the incorrect #10 wire. The #12 wire is the "light green with red stripe. The numbers are VERY small and they should be on it so maybe a magnifying glass?(got my first set or reading glasses just over a year ago---ahhh, the joys of aging!)
bruce

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 Posted: 08-14-2020 07:59 pm
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DonBurns
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Yes - I went to the trouble to write down the correct wires on a piece of paper, got under the dash and still got it wrong. Bonehead move. Anyway, corrected and this seems to have fixed the start delay. Thanks! Now no excuse not to take to body shop, except that I've spent all my money on outrigger canoes.

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