Question on Engine Temp

[chesnut]

Young1,

Thanks, will give the ye ole bicycle card a try.

Gary
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[HAWAIIZR-1]

Originally Posted by chesnut

Temp update

June driving on I45 stop'n'go traffic in Houston area - '92 turned off the A/C and regular temp gauge was in the "danger zone".

Since then:
1) installed Marc's chip to turn on fans at 205
2) replaced radiator with 2 row DeWitt's radiator

Short test drive this morning went well. Ambient temp was 88 degrees.
- Idled with A/C on while filing up with gas & temp got up to 230
- Drove back home
- Idle for 15 minutes in driveway with A/C on and temp digital gauge showed 240

Checked top of radiator with temp gun and it showed 140 degrees.

Is there an easy way to tell if the passenger side radiator fan is on? I'm having a hard to seeing the fan blades to tell if they're moving or not.

Thanks,

Gary
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What about if you keep your AC off then does your fans work and temps stays
down? If so, you have same issue as I do with AC pressure switch or high pressure.

https://www.zr1.net/forum/showthread.php?t=33274

[chesnut]

HawaiiZR-1

Please elaborate on your "AC pressure switch or high pressure" - am not familiar with this problem.

Thanks,

Gary
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[chesnut]

Young1,

Didn't need to do the bicycle card trick to see if the passenger side fan was running.

Pulled into the garage out of the sunlight and could see the passenger side working with a high powered flashlight.

Thanks,

Gary
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[chesnut]

HawaiiZR-1,

Early thought the A/C wasn't working correctly. The Tech checked both hi & low side and they have proper pressure.

Problem was bringing in the outside air. Tech recommended set to recycle air and all is good with 44 degree vent temp with 100 degrees Texas temp.

Did learn one thing when I attempted to put my gauges on the high side. Bought a Santech R12 high pressure port adapter for GM Deep Access 1991 & later part no.: MT0436

Thanks,

Gary
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[DRM500RUBYZR-1]

Buy an inexpensive Coolant Pressure Tester.
Check to see if it hits and holds approx. 14-15 pounds.
My car ALWAYS ran cool until it did not.
A very hot day car show procession up to and on the boardwalk at OC NJ and out of nowhere, I was suddenly at the danger zone and moving beyond.........

Radiator Cap was fine, but I had the smallest of leaks on the upper connection of the lower hose. Never left a drop underneath the car, ( must have evaporated near immediately ), but enough to keep the system from pressurizing.

All was fine (170-190) until stressed, then quickly out of control.

Once found, 1 minute to tighten the clamp and all was well again.

That $20.00 tester could save you hours of expensive diagnosis time at any shop.

Keep us posted of your findings or lack thereof.


Marty

[chesnut]

DRM500RUBYZR-1,

Appreciate your good suggestion about the coolant pressure tester.

Did the pressure test after installing new radiator earlier this month. Also replaced the pressure cap as a precaution and also tested it.

Out of caution, I recheck the clamps for tightness every time I take off on a Road Tour.

Was interesting for me to read that Chevrolet engineered C4's to run 220+ to help pass EPA standards. And used the same radiator through the C4 Corvette run without any regards to HP.

My '92 runs good temps around 200~212 with normal highway driving, even in hot Texas summer 105 degree temps, with A/C on as long as i keep the car moving. It's the stop'n'go traffic that I get stuck in, that causes the temp to creep up to around 240. Never had a Corvette run that hot before, ever. It's never puked. But this June it did shut off the A/C, which was a first.

Fixin' to head out on the NCRS Convention Road Tour. Installed new 2 row DeWitt radiator, Marc Heibeck's 170 degree thermostat and chip.

Thanks again for sharing.

Gary
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[chesnut]

Status report after driving 3,124 miles on the NCRS Convention Texas Road Tour to Hampton Roads, VA.

Before the trip upgraded the cooling system with a new DeWitts 2 row, new thermostat, Marc Heibeck's throttle body bypass tube & chip. Also, installed a debris screen.

When I removed the upper radiator shroud, found all kinds of trash on the radiator, etc. including a page from a porno magazine 2002 printing.

Trip to Hampton Roads - Engine temp was running 200 to 230 depending upon the gear and traffic. Stop'n'go traffic in 100 degree heat drove temp over 240 and to 250.

Air cleaner on car is the aftermarket Automotive Performance Intl. from Seattle, WA with the big scoop in front of the condenser and radiator.

In Ashville, NC decided to remove the scoop. Stopped by Harbor Freight and bought a compass hand saw. Roughly cut the scoop off of the air cleaner.

Return home trip with outside temp 95 to 100 degrees - cooling was improved 190 to 200 degrees at 70~75 mph in 5th & 6th gear. 50~60 mph in 4th gear up to 210 degrees. Stop'n'go traffic for over 30 minutes, engine temp never got about 235 degrees.

Every evening during the trip, cleaned road trash off of the debris screen, which before would've been sucked into the radiator.

Duh, never dawned on me the air cleaner's big scoop was restricting air flow to the condenser/radiator.

Appreciate everyone's help and advice.

Gary
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