slow heating
 

OK, Maybe someone has an idea,

http://i271.photobucket.com/albums/j...8/P4050109.jpg

Im pretty sure this is the factory set up. radiator recored, water pump ok, thermostat replaced, stock timing setting, clean coolant.

Problem: Sitting at idle the car will slowly heat, and continue to heat up very slowly, if I drive it will cool back down,

The assembly manual shows the setup as you see, assuming it is stock, any ideas?? It is now running a 180 standard themostat, oem appears to be 195. Assuming factory stock the system even though build without a shroud should run at the thermostate temp?? shouldn't it

Re: slow heating
 

No fan shroud ?

Re: slow heating
 

You could try drilling a 1/8" hole in the thermostate. This will let the air out of the cooling system that gets traped. Paul

Re: slow heating
 

Try a 160 stat in it. I never run anything over a 160 in these cars.

Re: slow heating
 

Operating temps of 195° and above were fine back in the day when we had decent gasoline, but these older carbureted cars simply do not seem to like to run right at those temps with today's gasoline. I can't begin to count how many complaints I've heard about running hot and constant heat soak/vapor lock problems on these older cars.

Also consider that the gas today is formulated for EFI (--there hasn't been a domestic carbureted vehicle available since ~1985). The ~10% ethanol in today's gas typically causes older carbureted cars to run a little lean, esp. at idle/low speeds, which can cause engine temps to rise.

I would first try adding a better fan and installing a shroud as suggested above. This alone may resolve the issue, but if not, you could try richening up the idle on the carb just a bit and perhaps try bumping the timing a little as well, that may help alleviate the creeping temps.

I'm also a big advocate of 160°-180° `stats in these older cars as well.

Re: slow heating
 

160 deg Milodon Thermostat! Best out there...
How old is that radiator core? Looks like it has miles on it.

Re: slow heating
 

The 160 degree stat is a good idea but I bet the lack of shroud is 'the' problem. What shroud design were BB Novas supposed to come with?

Re: slow heating
 

Shroud is a definite. Try a 1 inch bigger crank pulley, or a 1 inch smaller water pump pulley. On my 68 Impala I have put on a electric fan on the front(pusher) for if I'm in parades.
Peter

Re: slow heating
 

Also you can try "Water Wetter" that stuffs really helps.
http://www.summitracing.com/parts/RED-80204/

Re: slow heating
 

The fact that your fan is so small and you have no shroud is the problem. If you go with the shroud at the very minimum I think you will have it mostly under control.

Re: slow heating
 

Carl
B4 you go messing with the stat to much, add a shroud, good advice already mentioned.
Check the cap to see if it is holding @ 15#
If you do get to the stat add the 1/8" hole like Paul said, can't hurt.
As far as the stat, I do not always agree with going with a lower * stat, a 160 stat is not going to make a engine magically run cooler and may in fact make it run even hotter. Give the engineers some credit. A 160 stat will allow hot collant to run around without the proper dwell time it needs inside the radiator.
I run my L78 4.10 Camaro with a 195 stat and a 4 core radiator
and it runs cool even in traffic.

Re: slow heating
 

If that is a Nova then the radiator is completely wrong...also must have a shroud!! It appears to have a short water pump..is this a 68..?? the 68's had a fatory clutch fan with 5 blades. I also see a vacuum tube for the tranny...but, I don't see cooling lines..??

If you run the correct radiator and shroud, a good fan and the 160* stat..you should be fine. After those addtions you can look at fuel/timing issues to make it even better...if you need more info send me a PM.

wilma

Re: slow heating
 

usually if there is no stat at all it will cause an overheating problem. I also like the idea of a richer carb mixture, checking the rad cap, plus a shroud. Water wetter is a good idea too. I like that stuff.

Re: slow heating
 

Looks like a 67 SS396 Impala and you are in fact missing the #3903958 fan shroud. Not a real easy item to come by.

Re: slow heating
 

Somebody mentioned Nova in an earlier post??...thougt those were big car exhaust manifolds...wilma

ps..the storms over here...just a few rain drops left [img]<<GRAEMLIN_URL>>/smile.gif[/img]

Re: slow heating
 

I gotta agree with the group here that says &quot;get a fan shroud&quot;. An engine-driven fan like that is absolutely useless without having a shroud to direct the air flow thru the radiator. Also, that type fan shown is notorious for not moving much air with its' semi-flat blades with not much pitch. A nice, 5-bladed clutch fan would do wonders when coupled with a good shroud.

Re: slow heating
 

Sorry, I thought I mentioned it is a 67 impala. Kwizz, psyco some others know the car. I didn't want to run a shroud if at all possible i'm trying to keep the factory look. The radiator has been recored since the photo.

http://i271.photobucket.com/albums/j...P4050124-1.jpg

I was trying to keep the car stock, it does have an aftermarket exhaust, it is the born with drivetrain. The assembly manual does not indicate a shroud, the radiator frame is not set up for a shroud. I was thinkig of running a clutch fan.Also I was almost thinking maybe running the colder stat (180)was allowing the coolant to run to fast, Ill try some of the suggestions

Re: slow heating
 

First things first, do you actually have a problem:

You indicate that it will slowly heat up: what temp does it heat up to? Do you have a real mechanical gauge or an infrared heat gun to check the actual temp? Never trust the factory electrical gauge.

Remember, some of those so-called NOS temp sending units are way off when it comes to accuracy. Most aftermarket ones are crap, too.

I had one supposed resto sending unit that made the gauge read 220 when the car was at 160 - on my 72 T/A. Don't even get me started on the Chrysler combination temp gauge and voltmeter that moves up with the rpms and falls when you let off the gas. [img]<<GRAEMLIN_URL>>/rolleyes.gif[/img]

A vintage sender is the best bet for accuracy. Second best was the Wells TU5.

Here's some info when I tested a few senders:

http://forums.performanceyears.com/f...070&amp;page=2

Re: slow heating
 

It's mech guage, I was originally running a 195 and the guage would show 195 to 200 while driving, with the 180 stat the guage shows around 185 running. It was not guaged before and the sender must have been bad because it bulged the tanks (harrison) end of last year. I was able to save the tanks with the recore.

Re: slow heating
 

Is the mechanical gauge plumbed into the head or the intake manifold?

Re: slow heating
 

Intake

Re: slow heating
 

I am running with out a fan shroud too. I have a five blade on and its good. Try that,a clutch fan with five blades. Paul

Re: slow heating
 

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: COPO 70 RS/Z28</div><div class="ubbcode-body"> The assembly manual does not indicate a shroud, the radiator frame is not set up for a shroud.</div></div>

I was going to argue this as I have owned several 1967 396 and SS427 Impalas over the years and could have sworn they all had shrouds. After looking at some photos of the cars from the late 70's and early 80's with ones I could see, you are right, they did not.

However, my assembly manual shows #3903958 when used with RPO L35, with M35 or M40, L35 and N10 with L35 or M40, L36 and M40 with L72. Confusing.

Re: slow heating
 

Its weird, In the copy I have they show a shroud (i have to look later) I think on the air injection reactor equipment radiator mounting page &quot; A16 K19&quot; but, Sheet A4 shows the radiator assmb but doesn't reference a shroud and A4 looks almost exact to what I have. Also Sheet A3 of the assembly manual &quot;396 &amp; 427 - generator mounting , fan, belt &amp; pulleys&quot; designates L35 &amp; L36. It shows the 4 blade fan but strangely it doesn't give a part number for the fan it lists the fan as &quot; PRODUCTION PART&quot;

There is a reference to UPC 13 Radiator assmb and radiator shroud assmb but the UPC13 sheets are not in the copy I have, copy is the KEY term here.

Strange??????

I wonder if it has something to do with the fact that the car is a very low option car. Power steering only?

Re: slow heating
 

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 69SSZL1</div><div class="ubbcode-body">Also you can try &quot;Water Wetter&quot; that stuffs really helps.
http://www.summitracing.com/parts/RED-80204/
</div></div>

That water wetter is interesting I read the tech info on it, I never realized that glycol coolant / antifreeze actually was less conductive than regular water.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">removal of heat from an aluminum bar at 304°F by
quenching the bar in different coolants at 214°F under
15 psi pressure. Compare the time required to reduce
the temperature of the aluminum to 250°F, or the boiling
point of water at 15 psi. Red Line with
WaterWetter® required 3.2 seconds, water alone 3.7
sec, 50/50 glycol in water required 10.2 sec, and
100% glycol required 21 sec. Water alone required
15% longer, 50/50 glycol 220% longer, and 100% glycol
required 550% longer.</div></div>

Cool Stuff! [img]<<GRAEMLIN_URL>>/grin.gif[/img]

Re: slow heating
 

http://i13.photobucket.com/albums/a2...1/DSC03365.jpg

http://i13.photobucket.com/albums/a2...1/DSC03366.jpg