Bypassing the clutch switch

[Paul Workman]

Originally Posted by max76

Dynomite,
when i put the new relay the old one still works?

Jumping in...

Yes - referring to the existing START relay - still is in the circuit, except on a 90-92 the current load is drastically reduced, improving the reliability of that relay (and the clutch switch too, for those choosing not to bypass it).

Looking forward to Dyno's pix too.

P.

[max76]

Ok Paul, thank you
Yes we are waiting dynamite picture's...these are the most important pic's...
The new relay is 60-80 ampere?
Here, on ebay.it i saw only 40ampere relay...i hope are there in local dealer...

[max76]

Ok dynomite, i'll take the picture and in these days i'll go to the local dealer to buy it...
so, i can change the original relay because i think it's cooked!!!!!

[LGAFF]

http://www.zr1.net/forum/showthread....t=start&page=2

[Dynomite]

Look at this on eBay:

http://pages.ebay.com/link/?nav=item...d=110373059322

60 / 80 AMP RELAY SPDT SINGLE POLE DOUBLE THROW NEW 654

Since this thread is about bypassing the clutch switch I will explain step by step details of the Starter Relay Installation in a separate thread.

I have had several types of No Starts in 1991s and 1990s and the Starter Relay in conjunction with Starter Solenoid Restoration cured them all.
See item #2 Electrical Ground Connections and Installing Starter Relay

See also Starter, Starter Relay, Wiring Harness, Battery, and Plugs Tricks

Keep in mind the starter Solenoid wiring in this very early 1990 is 12 gauge red (NOT PURPLE) which is rare.

[max76]

Thank you so much!!!!!!!!!!
Great job dynomite!!!!!
So, with this modify the starter enable relay work better? Could be "fresh"...really?
Ok...in the next day i'll try to do the modify...but i think have the purple wire and not the red one....under the dash when i bypass the clutch switch i connect the yellow and purple wire, like in the paint of first page.

[Paul Workman]

Originally Posted by max76

Thank you so much!!!!!!!!!!
Great job dynomite!!!!!
So, with this modify the starter enable relay work better? Could be "fresh"...really?
Ok...in the next day i'll try to do the modify...but i think have the purple wire and not the red one....under the dash when i bypass the clutch switch i connect the yellow and purple wire, like in the paint of first page.

I guess I'm not understanding the point of installing the additional relay if you are bypassing the clutch switch, UNLESS the existing START relay is difficult to get to (I don't know). Adding the new relay will simply transfer the heavy current chores to the new relay, which would be good, but ONLY IF getting to the START relay is more difficult than removing the battery and changing the modification relay - that I don't know (haven't tried to replace it).

[max76]

I already bypassed the clutch switch about 2 years ago...

The new relay location is under the ecm...sorry but i don't understand what you are saying

[Paul Workman]

Originally Posted by max76

I already bypassed the clutch switch about 2 years ago...

The new relay location is under the ecm...sorry but i don't understand what you are saying

If you install the new relay circuit as I designed it,



the load on BOTH the existing START relay and the CLUTCH SWITCH is effectively transferred to the new relay without loosing any of the safety features! But, if you take the CLUTCH SWITCH out (by-passing it), you loose the safety feature and end up with a redundant relay (two in series).

The the question is: Without the CLUTCH SWITCH, is installing another relay justified?? Will the effort to install the new relay and then access it again later to replace it if need be, compared to simply replacing the original START relay justify the effort and expense of installing and maintaining the new relay??

I've never changed the original START relay, so I don't know what it would take to change one out. However, I intend to retain the safety feature afforded by the CLUTCH SWITCH, and so the auxiliary relay makes sense...maybe.

AND, as I said, a really good point made some time ago by Scottfab was you can eliminate all of the damaging arching in the CLUTCH SWITCH - even in the 90-92 cars IF you fully engage the clutch before turning the START switch, followed by releasing the START switch BEFORE releasing the clutch. That way the switch contacts are fully engaged before the high current load is applied, and the load is gone before the contacts are broken. (With this in mind, I'm less inclined to install that relay myself. But, rather have a spare START relay in the glove box...just in case.)

And, another thing: I'd rather go solid state whenever possible, as opposed to mechanical relays. And, I'm sure if someone wanted to use a FET transistor(s) for the switch instead of the auxiliary relay, it wouldn't be too difficult.

[max76]

Ok Paul....
So, before i install the second relay i want check the old relay and see (if it's possible) if internal components are damaged.
If they are damaged, first thing is change the old relay (obviously)...so, maybe the problem is only that.
This saturday i think to have just a little time to remove the protection and look the old relay conditions. I also can restore the clutch switch...
Someone, here in Italy, say to install a push button (temporary) to connect directly the battery with the starter, this in case i have te same problem, i can try if the problem is the relay or the starter...
Could be a different solution?