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unclenick
01-17-2005, 06:21 PM
I installed an underdrive pulley set (lower balancer pulley and water pump), the lower was smaller than stock but the water pump one was larger than stock. So the theroy is the water pump should be turning at the stock speed, right? But ever since installing the SC has been running warmer than normal. Usually she'll run at a operating temp between the R and M. Now, she' getting right to the M and going past before fans kick on. I have replaced the sensor for the fans, coolant temp sensor for the gauge and have flushed the cooling system also. I have also done a block test to see if the head gaskets were toast but, the blue test water did not turn green, so they are good.

If I run the car with the ac/defroster on the car stays cool, but if I dont the fans come on too late and she gets warm...fast. :confused:

When the car gets warm, I can turn the a/c/defroster on and she cools down quick. The funny thing is this did not start until I did the pulleys. I am going to try some Redline Water Wetter or some Royal Ice but, I think I need to address this issue of getting warmer than I like first.

Any suggestions?

MIKE 38sc
01-17-2005, 06:31 PM
Nick with underdrive pullies you slow down the water pump. Thats a very bad thing to do on the SC engine since its radiators reserve cooling capacity is 0.
You would'nt have any problems with a better radiator with more cooling capacity however, but thats more $$$.

unclenick
01-17-2005, 06:38 PM
Nick with underdrive pullies you slow down the water pump. Thats a very bad thing to do on the SC engine since its radiators reserve cooling capacity is 0.
You would'nt have any problems with a better radiator with more cooling capacity however, but thats more $$$.

The bigger radiator is coming, but it still makes no sense to me if the lower is smaller and the water pump pulley is bigger than stock, in theory it should be the turning the same for the water pump, right?

I guess I need to take the OD of the stock balancer pulleys and the stock water pump VS the new stuff and make sure it is the same OD for the water pump first.

David Neibert
01-17-2005, 06:38 PM
The water pump does turn slower with underdrives. The smaller crank pulley slows it down, and the larger wp pulley slows it down even more. If your fan isn't turning on until the temp gauge reaches the "M" then something is wrong.

If it was my car, I'd install a 180 tstat and wire in an adjustable controller for the fan. I've got dual controllers on mine to control both the low and high speed fan settings. It doesn't cost much and can be wired up in less than an hour.

If you just want to see if turning on the fan sooner will correct the problem, you need only to wire a switch into wire #14 of the ICRM to break the connection. Or just cut the wire and the low speed fan will run constantly.

BTW, My car always ran on the hot side until installing a big aluminum radiator.

David

tim
01-17-2005, 06:44 PM
I dont know if you have a chip or not but I think that with a chip you can program the fan to come on sooner. There may be another way to do it but Iam not sure. You can always get an extra fan that comes with the thermostat. Summit and jegs have them. My radiator had the metal tanks so I had it recored with an extra row not as fancy as aluminum but it was only $225 and with a 160 degree thermostat it never even gets to the middle. Tim

unclenick
01-17-2005, 06:49 PM
The water pump does turn slower with underdrives. The smaller crank pulley slows it down, and the larger wp pulley slows it down even more. If your fan isn't turning on until the temp gauge reaches the "M" then something is wrong.

If it was my car, I'd install a 180 tstat and wire in an adjustable controller for the fan. I've got dual controllers on mine to control both the low and high speed fan settings. It doesn't cost much and can be wired up in less than an hour.

If you just want to see if turning on the fan sooner will correct the problem, you need only to wire a switch into wire #14 of the ICRM to break the connection. Or just cut the wire and the low speed fan will run constantly.

BTW, My car always ran on the hot side until installing a big aluminum radiator.

David

Hey Dave, so I am wrong by thinking that it actually turns the same speed? This now makes sense, I had already planned on wiring in the fan to a switch so when drag racing, I do not need to have the def on to keep car cool in the pits. Also the 180 t-stat is on the way. Now if I put the stock pulley on the water pump and leave the lower alunimum pulley on the stock belt is too long. I stock size is an 8k897, I have found that the next size down is an 8k850 which is way too short. Is there another 8k size like an 8k870 or 8k875 I can find to use if I go this route?

I have installed a ton of parts on this car and am running on the 30th at OSW and do not want any problems.

unclenick
01-17-2005, 06:51 PM
David, I also noticed on your member page of the GM bigger air dam, Did you get this off a Camaro/Firebird? If so great idea! May I copy your idea?

unclenick
01-17-2005, 06:54 PM
I dont know if you have a chip or not but I think that with a chip you can program the fan to come on sooner. There may be another way to do it but Iam not sure. You can always get an extra fan that comes with the thermostat. Summit and jegs have them. My radiator had the metal tanks so I had it recored with an extra row not as fancy as aluminum but it was only $225 and with a 160 degree thermostat it never even gets to the middle. Tim


Tim, I do not have a chip yet. I will need one when the heads/cam goes in before the end of the month. I saw kit on Jegs last night.

David Neibert
01-17-2005, 07:11 PM
David, I also noticed on your member page of the GM bigger air dam, Did you get this off a Camaro/Firebird? If so great idea! May I copy your idea?

It's from a Grand AM or Cavilier (same on both cars). I copied the idea from Vernon Craidler. If you do a search on Air Dam you will find a post with GM the part number, hardware info and pics from when I first installed it about a year and a half ago.

I'm not sure about the belt length, but I would think NAPA would probably have something close enough. I've got wiring diagrams for doing the fan controls..let me know if you need them.

David

unclenick
01-17-2005, 07:24 PM
It's from a Grand AM or Cavilier (same on both cars). I copied the idea from Vernon Craidler. If you do a search on Air Dam you will find a post with GM the part number, hardware info and pics from when I first installed it about a year and a half ago.

I'm not sure about the belt length, but I would think NAPA would probably have something close enough. I've got wiring diagrams for doing the fan controls..let me know if you need them.

David

Yea, e-mail me the diagrams that would be so awsome! I did go to Napa and as a Goodyear Dealer, I have access to all kinds of belts and could not find one to fit. Guess I'll try the 180 t-stat and wire in the fans sooner. Thanks for all advise! It is a start!

David Neibert
01-17-2005, 08:53 PM
Yea, e-mail me the diagrams that would be so awsome! I did go to Napa and as a Goodyear Dealer, I have access to all kinds of belts and could not find one to fit. Guess I'll try the 180 t-stat and wire in the fans sooner. Thanks for all advise! It is a start!

Here's the wiring diagram Dave Dalke drew for installing dual controllers and a pair of relays. Doing it this ways allows the EEC to still have control of the fans in the event you set the fans to high or there is a blown fuse to the relay. It will also allow the fan to operate when the AC compresser is turned on. It also shuts down power to the low speed fan windings whenever the high speed is running, just like the EEC controls would.

http://members.tccoa.com/dneibert/fan%20relays.jpg

I just used a pair of generic adjustable thermostatic controllers I bought at Autozone and two automotive 30 amp relays. I bought the 1 amp diode at Radio shack.

David

unclenick
01-17-2005, 08:58 PM
Thanks man, I really am thankful for all the wisdom and help! :)

Let ya know how it turns out!

sail7seas
01-17-2005, 08:58 PM
Take a look at Delta Current Control.
http://www.dccontrol.com/

It is a variable fan speed control, and keeps the engine
at whatever temp you want by changing fan speed.
I have one and it works great.

unclenick
01-17-2005, 09:05 PM
Take a look at Delta Current Control.
http://www.dccontrol.com/

It is a variable fan speed control, and keeps the engine
at whatever temp you want by changing fan speed.
I have one and it works great.

That is pretty cool! Thanks :)