Date: Sun, 3 Sep 2006 21:25:21 -0500
From: "Faye" <[EMAIL PROTECTED]>
Subject: getting hot
WE ARE NEW TO THE OLDS FAMILY WITH 1969 442 YESTERDAY WE =
WENT TO SMALL TOWN PARADE AND OVERHEATED BAD ARE ALL OLDS =
SUBJECT TO RUN HOT?
WE HAVE A GTO WHICH RUNS WARM TO BUT WE KEEP HER DOWN TO =
AROUND 180 ON THE ROAD 218 IN HEAVY TRAFFIC ,BUT THE 442 =
RUNS AROUND 220 ON THE ROAD.
================================
Well, no, from the factory they did not run overly hot.
Therefore, something has changed to cause this condition.
IS THERE ANYTHING WE CAN DO ?
ANY HELP APPRECIATED
THANKS
Bob and Faye
=============================
Oh sure
First off, let's define HOT
Gages can lie [be inaccurate]
Is "hot" confirmed by touch test, or oh maybe thermometer test? Or, puking
the green juice onto the ground or into the overflow tank?
Not to cast undue aspersions on your diagnostic abilities, but I have seen
folks say "the car overheated" because the hose sprung a leak, and the steam
they saw translated to "overheated" in their mind. Not unlike the dolt that
called the FIRE DEPT when the wife crashed the 68 98 into a truck. Dolt
steps out of the BAR and sees STEAM and calls the fire dept. Which they sent
US a $250 bill for. Thanks... but I digress.
Seems to me like overheating come is one or both of these flavors:
1) making too much heat [possible but less common]
2) not getting rid if it fast enough. [more common]
2a) mainly during extended idle [more common]
2b) mainly during higher speeds driving
"1969 442" suffering from condition 2b above, eh?
Hmmmm..
the chance that this engine is stock and untouched is right about zero.
So, what-all has been changed from the correctly functioning factory system?
Do you have a later smogger 455 maybe?
When my '68 came to me, it had a '67 400 engine. That intake has no place to
put the Thermal Vacuum Valve that '68 models used, to alleviate overheating
at idle. Therefore, it did not have one, therefore, it overheated during
cruises, stuck in traffic, etc. Exacerbated by running crappy fuel.
If your engine is high compression, the timing was set to oh 10-12 degrees
and all was well in 1969. With leaded hi-ocatne fuel.
My car was in CA which required 1) retarded timing and 2) disconnect of
the dist'r vacuum advance, to comply with emisisons regulations at the time.
Maybe last year your driver buys 93 or even 87 octane. Engine detonates,
so timing gets retarded. Retarded timing leads to overheating, esp. at idle.
Running correct fuel and timing and finally fitting the correct thermal
vacuum switch to my car solved that issue. I run 25% 110 octane racing gas
and 75% 94 or 93 octane now, with proper timing, on the 1967 UHC 425 motor,
and it runs GREAT.
But your car runs hot even when driving.
So, we can assume pretty safely that airflow thru the radiator is not the
issue.
yes, you should have a 6-7 bladed clutched fan and the proper shroud and
shroud seals, and all that, but that is manly for at-idle airflow. In steady
state road operation, other factors should dominate.
Thermostat must be in place and functioning properly, of course. What else
gets changed typically?
Perhaps you can read the ID numbers, or number/ letter/ dot/ circle/
whatever on your water pump's RH outlet boss? It might be the wrong pump
[typically AC cars and some others have Y72 Heavy Duty Cooling which uses a
different water pump]. Rebuilt pumps often bear the cheesiest stamped open
pc of crap impeller they can obtain. Real factory pumps generally use a
closed-back cast iron impeller.
Perhaps you can read the ID on the crank and WP pulleys, or at least
measure or roughly guess their diameters? At least look see whether crank
pulley is larger or smaller than the WP pulley, and by how much. Pulley
sizes determine the ratio of WP speed to engine speed, and are part of the
engineered PACKAGE that worked just fine when it left the factory.
If there's any doubt at all about the radiator's ability to dump the heat-
thermometer ck at inlet and outlet should show a large temp drop across the
radiator- then a new one is in order. As mentioned before, go with at the
very least a 3-row, preferably 4-row. It's pretty easy to jerry-rig a 4-row
in place of the 3-row, though a bit tougher on the '69 models because the
radiator top plate holder C's are formed right into the part, not just a
part welded onto it. Thus the $300 price for used 4-row plates I guess.
http://cgi.ebay.com/69-72-Cutlass-442-4-Core-Radiator-Top-Plate-W30-W31_W0QQitemZ200020329731QQihZ010QQcategoryZ10076QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
[ebay item 200020329731 ]
http://cgi.ebay.com/69-72-CUTLASS-442-W-30-UPPER-4-CORE-RADIATOR-TOP-PLATE_W0QQitemZ250022822128QQihZ015QQcategoryZ10076QQrdZ1QQcmdZViewItem
[ebay item # 250022822128 ]
Not all radiators are equal either. Many times you can get one with the
wrong size hose nipple, bottom right typically. Many makers skimp on copper-
it is rather pricey- and put in smaller tubes and far fewer FINS, which of
course drastically affect the radiator's ability to, uh, radiate the heat
away. Your new radiator should be HEAVY.
Speaking of the bottom hose... unless it has the spring inside it, coolant
flow and suction of the pump on a partially clogged radiator can suck the
hose shut. I have seen it happen. Watch your lower hose as you rev your
warmed engine to oh 2-3000 RPM. If there is a problem there, it will be
immediately obvious. This will happen manly while you are driving at higher
than idle speeds, and so you will never SEE it happen unless you test per
above.
no one mixed green and red coolant in the car, did they? My brother's gf's
mustang engine recently died from that snafu. Turns to sludge and clogs the
radiator.
Most likely cause: old, inefficient, clogged radiator, or dysfunctional
thermostat.
other factors above might also contribute.
-----------------------
Chris Witt
*the* Rocket Scientist
1303 W. Miller Rd.
Lansing MI 48911
[EMAIL PROTECTED]
Cell 517-449-0432 weekends or short weekday calls or leave message.
Home 517-882-9747 thru 10-11pm MI time most days
