Update on my hi-miler Z project

[limey]

Andrew,

1st off, i'm thrilled to no end that the motor is running and no "issues". I trust you have good oil pressure and no lifter noise etc. As to the temp readings, a couple things and the most likely is air pockets in the system, or a sticking thermostat.

If the car is idling still, do both fans come on and then turn off once cooled?

Also remember, this motor is built to factory spec, so it's going to be a bit tight for a while, not loose like your old 180k mile one so that i'm sure is going to also play into a bit warmer running temps than what you was used to seeing in your old motor.

Now, back to the rebuild :-), it would appear that for $4500.00 exchange and warranty, that this is the best possible route to go now, Much cheaper than anyone could buy the parts for, not to mention the cost of labour to rebuild.

[Blue Flame Restorations]

Originally Posted by limey

Andrew,

1st off, i'm thrilled to no end that the motor is running and no "issues". I trust you have good oil pressure and no lifter noise etc. As to the temp readings, a couple things and the most likely is air pockets in the system, or a sticking thermostat.

If the car is idling still, do both fans come on and then turn off once cooled?

Also remember, this motor is built to factory spec, so it's going to be a bit tight for a while, not loose like your old 180k mile one so that i'm sure is going to also play into a bit warmer running temps than what you was used to seeing in your old motor.

Now, back to the rebuild :-), it would appear that for $4500.00 exchange and warranty, that this is the best possible route to go now, Much cheaper than anyone could buy the parts for, not to mention the cost of labour to rebuild.

Gotta say it again, Kurt. YuDaMan! What a great price for what you have done!

[VetteMed]

Originally Posted by limey

Andrew,

1st off, i'm thrilled to no end that the motor is running and no "issues". I trust you have good oil pressure and no lifter noise etc. As to the temp readings, a couple things and the most likely is air pockets in the system, or a sticking thermostat.

If the car is idling still, do both fans come on and then turn off once cooled?

Also remember, this motor is built to factory spec, so it's going to be a bit tight for a while, not loose like your old 180k mile one so that i'm sure is going to also play into a bit warmer running temps than what you was used to seeing in your old motor.

Now, back to the rebuild :-), it would appear that for $4500.00 exchange and warranty, that this is the best possible route to go now, Much cheaper than anyone could buy the parts for, not to mention the cost of labour to rebuild.

Kurt, thanks for the feedback. No lifter noise, no other issues noted at all. Oil pressure indicated on the gauge is about 60 cold, 35-40 hot. Idle is a little rough at times, but I am attributing that to either a poor seal on the o-rings for the PCV breather tubes, or possibly a lingering injector issue.

The fans do in fact turn on when the gauge indicates about 3/4 of the way up, and turn off after cooled (not sure exactly what point that is at though).

Agreed that the price paid is a screamin' deal relative to what it would have cost me otherwise. My car would have been dead in the water for many months to come, were it not for this option. Thanks again, Kurt!

Sammy's mention about the aftermarket temp sensor is interesting. I did replace the OEM sensor with an aftermarket. However, the one I replaced was the one-terminal "button" connector arrangement, not the 2-wire weatherpack connector. I "assume" that the one-terminal sensor is for the gauge, while the 2-terminal is for the ECM?

Edit: looks like my ASSumption was correct, the sensor I replaced controls the dash gauge. So that most likely is the reason for the perceived warmer temps. I'll have access to a scan tool next week, and I'll try to determine what the ECM is seeing so that I have a mental framework for comparison to the dash gauge readings.

[A26B]

Originally Posted by VetteMed

........
Sammy's mention about the aftermarket temp sensor is interesting. I did replace the OEM sensor with an aftermarket. However, the one I replaced was the one-terminal "button" connector arrangement, not the 2-wire weatherpack connector. I "assume" that the one-terminal sensor is for the gauge, while the 2-terminal is for the ECM?

Edit: looks like my ASSumption was correct, the sensor I replaced controls the dash gauge. So that most likely is the reason for the perceived warmer temps. I'll have access to a scan tool next week, and I'll try to determine what the ECM is seeing so that I have a mental framework for comparison to the dash gauge readings.

You are correct, the single, button terminal provides coolant temp signal for the gauge & the other 2 terminal sensor provides signal for the ECM & the cooling fans.

I have a 94 which is different, but doesn't yours also give you a digital readout by pushing a couple of buttons? may be in centigrade but at least you could tell what the other sender is reading through the ECM. The scan tool will be reading the same thing.


Someone with a 90~92 could offer some input here.

[VetteMed]

Originally Posted by A26B

You are correct, the single, button terminal provides coolant temp signal for the gauge & the other 2 terminal sensor provides signal for the ECM & the cooling fans.

I have a 94 which is different, but doesn't yours also give you a digital readout by pushing a couple of buttons? may be in centigrade but at least you could tell what the other sender is reading through the ECM. The scan tool will be reading the same thing.


Someone with a 90~92 could offer some input here.

The HVAC control head can display the temperature in C. I forgot all about that today, but am going to check tomorrow. I posted the procedure in the "engine warm up" thread.

Jerry, do you know what size the proper o-ring is, for the PCV breather tubes that run from the cam cover to the throttle body? None of the o-rings I have, seem to make a good seal.

Andrew