Don't start

[max76]

Hi guys!!!How are you???
I hve a little problem with my Z...
Yesterday i run with the Z about 20 miles, it's run great as always...
I'm back home and turn off the engine.
I wait about 10 minutes and when i turn the key the starter don't run.
I have already bypassed the clutch switch and the VATS...when i turn the key the security light on the cluster is OFF.
I leave the car for about 2 hours and i try again...the engine start without problem!!!
So, could be the injection relays?It's old and could be bad...
I think it's original, my car has about 25000miles.
Any ideas?Suggestions?
Thanks in advance
Bye from Italy!!!!
Max

[GOLDCYLON]

Im thinking the starter or the Starter solenoid may be failing?

However when you state it wont start will it still crank ?

[max76]

No Gold...when i turn the key on there is perfect silent!!!!!
There is Dynomite in other discussion thet help me to put a new relay...i hope it's a good job and resolve the problem...
the contact into the starter are new...last year i change it...

[GOLDCYLON]

ok lets hope the relay fixes the issue.

[max76]

i hope too!!!
thanks

[Dynomite]

ok lets hope the relay fixes the issue.

Several things I do to ALL ZR-1s.

1. Change ALL fluids.
2. Block TB Coolant at the Injector Housings.
3. Install Differential Drain Plug.
4. Clean Radiator and install Radiator Screen.
5. Install Starter Relay. :D
6. Install Marc Haibeck Chip. ;)

Electrical Ground Connections and Installing Starter Relay (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-3.html#post1581564089)

http://i287.photobucket.com/albums/ll142/dynomite007/Dynomite6/2844c361-c225-4c5b-be61-a3129d0d14b0.jpg

[max76]

Dynomite, if I install the starter relay, the original starter relay still work? Or I must remove it?
Thanks in advance
Max

[Dynomite]

Dynomite, if I install the starter relay, the original starter relay still work? Or I must remove it?
Thanks in advance
Max

Do not remove anything.......what happens is that the new relay just takes all the current directly from the battery directly to the starter Solenoid (now a direct and unencumbered path) and the smaller current to operate the new relay goes through the clutch switch and original relay. The current load in the original starter solenoid circuit is greatly diminished.

The main current load to the starter windings is and was directly from the battery to the Starter windings through the closed solenoid points.
Those Solenoid points should be dressed up at some point in time next time you have the plenum removed as that in itself is often the cause of a NO START (poor current path through the Starter Solenoid Points).

That is not to say that you have not burned up the original components in that original starter Circuit beyond help ;)
In my cases I have never seen any starter issues after installing the new starter relay and after taking some emory cloth to the starter solenoid points. Make sure you have an excellent ground wire connection when installing the new starter relay and new ground wire.

This is assuming the two bearings on each end of the starter armature are in good condition and that the starter has not been submerged in water at some point in its life with a flood in the valley because the valley drain is plugged. This after the LT5 was cleaned by pressure washing which is a BIG NO-NO with the LT5 engine.

See Starter Relay, Wiring Harness, and Plugs Tricks (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-3.html#post1581564085)

[max76]

Dynomite, some weeks ago i removed the plenum and change the starter with a new ones (overhaul) bought from ebay.
I have the original one but i don't know if is in good or bad condition.
So, if i have correctly understand the no start condition is because there is a lot current in the starter windings? And the solution is put the second relay...correct?

[Dynomite]

Dynomite, some weeks ago i removed the plenum and change the starter with a new ones (overhaul) bought from ebay.
I have the original one but i don't know if is in good or bad condition.
So, if i have correctly understand the no start condition is because there is a lot current in the starter windings? And the solution is put the second relay...correct?

No......we are talking about the Solenoid windings in this case.

There is a fair amount of current in the Starter Solenoid windings and the solution is to install the relay which takes current directly from battery to the starter Solenoid windings (connected to the Purple Wire to Starter Solenoid).

The starter armature windings already take current directly from the battery but you have to make sure your positive and negative battery connection and ground wires to the engine are in good condition. As well as the main positive lead from the battery to the Starter main post with the Nut on it.

The purple wire that you splice and connect to the new relay goes to the "plug" connector on the starter Solenoid. You also make a new ground wire to that relay that has to have good contact with the frame. And you also make a New "Hot" (same gauge as purple wire) that goes from the larger 3/8 inch post on the new relay to the multiple HOT Connector between the battery and fire wall.

The better the connections to the Solenoid from the battery the greater the magnetic field and force that closes the Solenoid Contacts.
The better the battery connections and ground to the engine the better the magnetic field that rotates the starter Armature and the greater the starter torque.

[max76]

Ok dynomite, I think to have understand the problem.
When I remove the plenum I clean all the ground wire above the flywheel case with sand paper and after I put some dielectric grease.
I also put a new ground wire direct from battery. I hope this is a good job!!!
Ok...in next days I'll put the new relay...and I hope I haven't no more starter issues...
thanks for the moment...
Max

[max76]

These are my starters contact's...I change them about a year and half ago...I think they are in very good condition...what I can check to understand if it has some internal issues?
Thanks in advance

[XfireZ51]

Max,

If you have it apart, I would just change contacts and clean up the rest. As others have said, it doesn't take much current loss to cause a no start. Also make sure the clutch safety switch is not intermittent.

[max76]

Hi Dom,
I already bypass the clutch switch and vats system.
I replace the old (and original) starter with one rebuilt bought on eBay.
I want to be sure that the problem is the starter, and I want to be sure that I solved the problem...