Sometimes don't start

[max76]

Hi Guys,
How are you???
I have a little big problem with my Z.
It's happen 2 times that the starter don't run.
When the car is hot, sometimes the starter don't run. You can turn the key on, push the clutch pedal, the security light off but all dead.
I by-pass the imobilizer(vats) with the resistance and the car run great, but now i have this problem.
What can be???What i can test?
Thank you so much for help!!!!:)

[tccrab]

This dreadful condition is commonly known as the................
"DREADED NO START."
http://www.zr1netregistry.com/forum/showpost.php?p=64480&postcount=2

Before you hack in to your wiring harness to perform my patented DNS Mod, there's quite a list of things to check first.
Have you recently washed the engine of your car?
If so, you're probably going to have to replace the starter.
http://www.zr1netregistry.com/forum/showthread.php?t=593
-Battery
-Battery cables
-Battery connections
-Measure starter voltage
-Check VATS
http://www.zr1netregistry.com/forum/showpost.php?p=3842&postcount=4
-Jumper out the Clutch Safety Switch
http://www.zr1netregistry.com/forum/showpost.php?p=10180&postcount=16
-Replace the Starter Relay
-Remove the Starter and have it tested
-Resist the temptation to throw heavy objects and stay away from any flammable liquids and matches.

TomC
"Crabs"

[max76]

This dreadful condition is commonly known as the................
"DREADED NO START."
http://www.zr1netregistry.com/forum/showpost.php?p=64480&postcount=2

Before you hack in to your wiring harness to perform my patented DNS Mod, there's quite a list of things to check first.
Have you recently washed the engine of your car? No, i never wash the engine
If so, you're probably going to have to replace the starter.
http://www.zr1netregistry.com/forum/showthread.php?t=593
-Battery New battery, i change it last year
-Battery cables Good conditions
-Battery connections New screw when i change battery
-Measure starter voltage How i can measure it?
-Check VATS I bypass the vats with resistance and run great
http://www.zr1netregistry.com/forum/showpost.php?p=3842&postcount=4
-Jumper out the Clutch Safety Switch I'll try this
http://www.zr1netregistry.com/forum/showpost.php?p=10180&postcount=16
-Replace the Starter Relay I'll replace the relay as soon as possible
-Remove the Starter and have it tested I can remove from the top of the engine?
-Resist the temptation to throw heavy objects and stay away from any flammable liquids and matches.

TomC
"Crabs"

Tom, thank you so much for the list of check. I hope that is the relay...to remove the starter i must remove the plenum?
Thanks in advance

[tccrab]

Tom, thank you so much for the list of check. I hope that is the relay...to remove the starter i must remove the plenum?
Thanks in advance

To get to the starter the plenum & coil packs must be removed.

Starter voltage can be measured at the clutch safety switch.
If voltage is less than 9.5v, starter won't engage.

TomC
"Crabs"

[jonszr1]

dont mean to hijack this thread . but i am having a starter prob. when i turn the key it clicks it does this 2-3 times then the starter engages . does that mean i have a selinoid going out . and does anyone know where i can get a selinoid if thats it .thanx

[DaveK]

dont mean to hijack this thread . but i am having a starter prob. when i turn the key it clicks it does this 2-3 times then the starter engages . does that mean i have a selinoid going out . and does anyone know where i can get a selinoid if thats it .thanx

It could just be the battery. If it's old the voltage may be starting to drop and I know (from personal experience!) that you really need peak performance to start the LT5.

Thanks

Dave

[jonszr1]

i just replaced the battery,as i thought that was it .but darn its still doing the same thing .

[max76]

Thank you so much guys...for me the 90% is the starter..it's a problem legacy to the temperature.
When hot sometimes don't start but if i turn the key there is an absorption. When the temperature go down it's start as never happen.
As i write the battery is new (1 years old) the vats is bypass, i think that if was a clutch switch problem it never start...or not??

[jonszr1]

best way to ck for the clutch switch is to watch the volt gauge while trying to start the car. release and press in om the clutch id the gauge goes down when you press it in the switch is ok

[max76]

Sorry jonszr1...i don't understand what you write.
May you explain better??Sorry, with simple words:confused:

[tccrab]

Sorry jonszr1...i don't understand what you write.
May you explain better??Sorry, with simple words:confused:

Watch the Voltage Gauge on dash when pushing down on clutch.
If needle moves, clutch switch is OK.

Your no-start is related to temperature, correct?
The next time you have a no-start, measure the battery voltage with a volt meter.
It is possible to have a battery that is weak when the car is hot.
It could also be that your starter is weak when it is hot.

TomC
"Crabs"

[VetteVet]

I've been watching this thread and decided to offer my .02. I had temperature related problems with my starter not cranking after a hot shutdown, but would start fine after the car cooled down. What I found was that a modification to the solenoid was needed. For anyone who has disassembled their starter, you will be familiar with the tapered rubber "bumper" on the solenoid slug. It seats tightly into the cavity in the stamped metal solenoid cover. What I suspected was that the air in that cavity was heating up and then when the engine was shut down, the cooling air was drawing a vacuum in the cavity and preventing the slug from being moved during starting. After sitting for a while, the slight amount of leakage between the shaft and "bumper" was enough to release the vacuum and allow a start. I ground a slot in the "bumper" to prevent it from sealing against the solenoid cover. I have not had any problems since then. BTW, no other work was done to the starter, so I am fairly sure that it was the mod that solved a design problem with the solenoid.

[DDSLT5]

best way to ck for the clutch switch is to watch the volt gauge while trying to start the car. release and press in om the clutch id the gauge goes down when you press it in the switch is ok

Good way to burn out the clutch switch real quickly.

[DDSLT5]

I've been watching this thread and decided to offer my .02. I had temperature related problems with my starter not cranking after a hot shutdown, but would start fine after the car cooled down. What I found was that a modification to the solenoid was needed. For anyone who has disassembled their starter, you will be familiar with the tapered rubber "bumper" on the solenoid slug. It seats tightly into the cavity in the stamped metal solenoid cover. What I suspected was that the air in that cavity was heating up and then when the engine was shut down, the cooling air was drawing a vacuum in the cavity and preventing the slug from being moved during starting. After sitting for a while, the slight amount of leakage between the shaft and "bumper" was enough to release the vacuum and allow a start. I ground a slot in the "bumper" to prevent it from sealing against the solenoid cover. I have not had any problems since then. BTW, no other work was done to the starter, so I am fairly sure that it was the mod that solved a design problem with the solenoid.

Pics are necessary!:hello:

[max76]

I've been watching this thread and decided to offer my .02. I had temperature related problems with my starter not cranking after a hot shutdown, but would start fine after the car cooled down. What I found was that a modification to the solenoid was needed. For anyone who has disassembled their starter, you will be familiar with the tapered rubber "bumper" on the solenoid slug. It seats tightly into the cavity in the stamped metal solenoid cover. What I suspected was that the air in that cavity was heating up and then when the engine was shut down, the cooling air was drawing a vacuum in the cavity and preventing the slug from being moved during starting. After sitting for a while, the slight amount of leakage between the shaft and "bumper" was enough to release the vacuum and allow a start. I ground a slot in the "bumper" to prevent it from sealing against the solenoid cover. I have not had any problems since then. BTW, no other work was done to the starter, so I am fairly sure that it was the mod that solved a design problem with the solenoid.


May you put someone picture please???
Thanks

[max76]

Watch the Voltage Gauge on dash when pushing down on clutch.
If needle moves, clutch switch is OK.

Your no-start is related to temperature, correct?
The next time you have a no-start, measure the battery voltage with a volt meter.
It is possible to have a battery that is weak when the car is hot.
It could also be that your starter is weak when it is hot.

TomC
"Crabs"

Yes, only with hot temperature, but not always...sometimes there is something work bad....

This test:Watch the Voltage Gauge on dash when pushing down on clutch.
If needle moves, clutch switch is OK.
I must do it when i have strat problem??
I have see the dash light go down when i turn the key and the engine don't run.
For this i think that is a problem of starter...

[jonszr1]

Good way to burn out the clutch switch real quickly.sure if one does it all the time .but doing it once in a while when having a starting problem shouldnt hurt it .

[jonszr1]

you could be right .starter might be drawing too much voltage

[VetteVet]

I can get some pictures this evening when I get back home from work. As it so happens, I have the motor out of the car right now for modifications.

[max76]

I can get some pictures this evening when I get back home from work. As it so happens, I have the motor out of the car right now for modifications.



We wait your picture!!!!!;)

[VetteVet]

Here is the picture:

http://i827.photobucket.com/albums/zz195/vettevet/Starter.jpg

The tapered rubber bumper seals very well in the radiused cavity in the cap. At this point, I have to apologize. I did not modify the bumper as previously stated (senility is apparently starting to set in). I debated modifying the bumper or the cover and chose to modify the cover. I cut a very shallow groove in the metal cover (visible at 12 o'clock in the picture). This prevents a vacuum from forming in the cavity and preventing the main contact (copper disk) from engaging and directing battery voltage to the starter motor windings. This only occurs after running to temp AND after a short cooldown period. Immediate restarts or waiting a substantial period of time do not cause any starting problems. When a no-start occured, I noticed a slight, but noticable drop on my volt gauge (due to solenoid energizing), but not a large drop (indicative of the starter windings being energized). If these are your symptoms, then this may work for you. I had numerous no-starts prior to this mod, but with several months of use after the mod, I never once experienced another no-start.

Jep

[max76]

Vettevet, but the modify is only a groove for prevent vacuum?
Which problem create the vacuum into the starter?
Is this the common problem of these starters?Also for zr1?
I thought that was a mechanical problem into the starter...
Thanks in advance

[VetteVet]

Vettevet, but the modify is only a groove for prevent vacuum?
Which problem create the vacuum into the starter?
Is this the common problem of these starters?Also for zr1?
I thought that was a mechanical problem into the starter...
Thanks in advance

max76,

When the solenoid is not energized, the tapered rubber "bumper" is seated in the radiused cavity of the solenoid cover by spring pressure. As the engine heats up, so does the air in that cover cavity. The heat causes the air in the cavity to expand and pressurize the cavity. That pressure works it's way out because the taper of the "bumper" and the radius of the cavity allow it. Once the engine is shut down and the air in the cavity starts to cool, it contracts and the pressure drops. This causes a vacuum to be drawn, which firmly seats the tapered "bumper" in the radiused cavity. In effect, the solenoid slug and main contact disk are held firmly in place. When the solenoid is energized at this point, the magnetic field created by the solenoid windings is not sufficient to overcome the force holding the slug and main contact disk in the deenergized position. The result is that the solenoid coil energizes, but battery voltage is not directed to the starter, because the main contact does not close. Result is a no-start. Hopefully, this will clarify things. Sorry for not explaining it better from the start.

Jep

[max76]

Vettevet,
am i that i don't know a better english, but i think to understand the problem...I hopr to repair soon my starter...
An other question, is so difficult remove the plenum and other parts for remove the starter?
There is a particular procedure?
Thanks a lot to everybody

[VetteVet]

Vettevet,
am i that i don't know a better english, but i think to understand the problem...I hopr to repair soon my starter...
An other question, is so difficult remove the plenum and other parts for remove the starter?
There is a particular procedure?
Thanks a lot to everybody

max76,

Here is a link: http://www.zr1netregistry.com/plenum.htm

Lots of good info on the ZR-1 Registry site!!

Jep

[max76]

Thanks vettevet