67 skylark overheating...

S

soul player

Guest
Question

on the 67 GS340 I just recently bought I changed the water pump,hoses,180 thermostat,and a new radiator. As i drove around everything would be ok according to the temp. gauge however, when i come to a stop (fastfood places, train tracks, long stop lights) the temp. would creep up slowely to 200-210 eventually..

i changed the thermostat today to a 160 thinking maybe I had a faulty thermostat but it still tends to creep a bit. I know when you stop the fan is not moving as fast but it seems to keep rising

what am I missing?? are these cars prone to this, should I be worried?? how hot is too hot?

thanks for any help
 
Soul,
First of all, the car should not be running hot, if anything the older cars ran cooler than the new ones.
Now ... usually when a car runs hotter at slow speeds and idle conditions, it is an airflow problem. Does the car have a fan shroud on it ? If not, that is the first thing to be installed. Second, if it has a clutch type fan, make sure the clutch is good. A good test is to get the engine good and hot, then have someone turn off the key while you watch the fan. If the clutch is working properly, the fan should stop turning almost instantly when you shut off the engine. If the fan keeps spinning for a few turns, the clutch is your problem.
Hope this helps,
 
Billk,

thanks for the reply, it ia a automatic, funny you mention it though, my fan shroud is intact but a piece was cut off on the bottom portion of the shroud by a mechanic that i had work on the car when i first bought it. after changing the oil pan seal and supposedly changing the rear main seal he could not mount the fan shroud back on right.... (see post "new to the forum just bought a buick")

I would not think that even part of the bottom piece would effect the air flow but now that you mention it, It looks like it could. I guess i will have to buy a new one. thanks again
 
could it be anything else if it was not the fan shroud?
 
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Hi Soul Player

Do You have a Clutch Fan or a Fixed Fan Blade? I don't mean to be a Smart Alic, but I don't want to leave any stone unturned. When You Filled the Radiator did You put in a Rust Inhibitor, the right mix of Anti-freeze and a Water Pump Lubricant? Also when Filling the Radiator (I know this is Summer) Did You let the car run and heat up and did you turn the heater on. Turning on the heater lets you add more fluid, but increasing the Volumne and Capacity of the Cooling System, making it more Efficient.
Most Failures in cooling are caused by blockages in the Radiator. You Said that You put in a New Radiator. Is it the Correct size and Capacity? You wouldn't be the first person that received the wrong part from a Vendor/Supplier. I'm just playing the Devils Advocate here. It sure sounds like You are doing all the right things and your car shouldn't be running HOT. I'm just trying to pin-point the problem, in hopes of correcting your situation.
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Tom Gallagher
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My guess would be shroud/clutch, but not meaning to be a smarta##, but here some thoughts that surprised me. and some that didn't. Overheating occurs when the coolant turns to steam, and is no longer able to carry the heat away. 50/50 AF/water mixture at 15 lbs. pressure (66 lasabre would've been 12 or 15, not sure) raises boiling point to 268 deg. Most newer cars are running 16 lbs or more, and since his rad. is new I think that would be safe. Engineering studies have shown that best thermal efficiency occurs when coolant is in the 215 degree range. If money is not a big object, I recommend new fan shroud and new fan clutch, maybe 16 lb cap, and after making sure it stays cool at long idle, 195 thremostat.
Theskylark62
 
Oops, sorry,
forgot to mention installing antirust and 60% AF/water mix (up to 70% is acceptable according to AF lables, but no higher because efficency drops off sharply above 70) and maybe a coolant enhancer. It's all about controlling the movement of heat.
Dan
 
Just as another tag on cooling...

I have found that, if a major cooling loss occurs and the person does a repair and fills the rad with straight water, failing to add a rust inhibitor for several days or a week, a rust coat can develop in the block which will inhibit the movement of heat to the coolant enough to cause overheating. A good flush can be tried, but in many cases the coating can only be removed thoroughly by disassembling the engine and "hot tanking".
 
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Hi, Fellow Buick Enthusiasts,

Another Element, that I Strongly Recommend is Do Not leave Anti-Freeze in the Cooling System for over a Year. After a years time a Chemical Reaction takes place and starts Eating Away at the Soldier Joints in the Radiator. In Colder Climates it is even More Important since a Higher Percentage of Anti-Freeze is used. Living in a Northern Colder Climate Around Thanksgiving I Flush out the Entire System and refill with the Correct Anti-Freeze Mixture for my climate about 20 below.I also add water Pump Lubricant and a Rust Inhibitor. Around Easter I drain the fluid off for a 20-30 degree climate. and that should take you till Turkey day, when you flush the entire system.
Also a Reminder The New Red Antifreeze and the Standard Green Antifreeze DO NOT MIX. They are made of different Chemical Composition and Compounds. If Your Newer Model Car cam with RED Anti-Freeze Stick with it. It is Good for 5 Year and 100,000 Miles. For Older Cars, used only the Green. The Subject Matter may Seem Insignificant, but it is Very Important.
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Tom Gallagher
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How many blades does the fan have on it? It should be a 18 inch 5 or seven blade fan from the factory. When was the last time that the motor was flushed? Have you checked for a possible blown headgasket?
 
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Gentleman and Buick Enthusiast's

As Arron simply stated, and put in Prospective. The Number and Size of the Fan Blades have an Intrigal Part in the Cooling Process. Also, Do You have a Clutch Fan? Is it in Proper Working Order?

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Tom Gallagher
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Fellow Buick Enthusiast's

There are Two (2) Things that Destroy an Engine, and I Think that We All are in Complete Agreement Here. It Breaks Down to Heat and Dirt. Plain and Simple. Engine Design has Created Filters to Eliminate a lot of the Dirt which Accumulates over Time. Damage caused by Excessive Heat can Destroy an Engine in a Matter of Minutes. :( :mad: :eek:
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Tom Gallagher
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Hey Tom

Sorry for the much delayed reply guys. I was on a little vacation, I think it is a fixed fan. No I did not put any water pump lubricant, No I did not let the heater run when i put the fluid. I did do 50/50... I have a new fan shroud, I have not put it in yet. the piece that is missing on the old one is small. I dont think that it would effect the temperature though. There is no oil or coolant mixing with eachother from what I can tell.

The radiator that I bought deffinately is not expensive. I was told that it was identical to the original. the previous radiator was a old recore that was leaking. I suppose i can buy a better one.

I was told that it could maybe be the egnition timing... I guess i will do everything all over again...
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Thanks for all your help guys...
 
Don't be so quick to blame the radiator just because it was inexpensive, it may actually be more efficient than the OE. Look inside under the cap and see how many rows of tubes are there. As a general rule todays replacements have better designed cores that release the heat faster than the old ones. I have seen 2 row replacements that cool better than 3 or 4 row OE's. Check ignition timing, do a compression check, what color is your coolant now? If its brown already, flush system thoroughly with a H.D. flush and add antirust/water pump lubricant with fresh coolant. I also recommend a coolant enhancer. There are many on the market, some better than others, but they can make a difference. How many blades on fan?
Let us know
Dan
 
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Hey Soulplayer!

Hey Dude, Slow Down! Do You have an Owners Manual for the Car. Find out what the Cooling Capacity Fluid Volumn is. Maybe another Member who has one if You don't can help us out here. Maybe Your Thermostat isn't opening a 10 buck part. Add the Rust Inhibitor and Pump Lube, let it run open up the heater so the fluid circulates into the heater core. You will probably be able to introduce 3 or 4 quarts of fluid into the system. Drive the car around for about 15-20 minutes.Turn on the Heater-Defroster make sure it is blowing hot air, if not, you don't have enough fluid. Put her to Bed and then check the fluid levels cold the next day. add fluid if necessary
I would follow this procedure before doing anything drastic. I hope this is the Solution to You Problem.
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Let us know how you make-out
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Tom Gallagher
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Cooling capacity for a 340 in '67 is 10.58 qts. with heater, 10.17 without, and 12 .25 with air.

I expect the 340 used a double thick rad, and your new one is probably adequate just as the fellows above have suggested.

Something I always do is drill a 1/16" hole in thermostats to eliminate the possiblility of air locking.
 
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Hey Soul Player!

How are Things Progressing with Your 340?
Have You worked out the Kinks in Your Cooling System?
I'm just trying to HELP! You out the Best I can. It's Tough trying to help out with a key-board instead of tools. I hope You find the Key to Unlock the Door to your Problem. Sometimes You just need a little moral support.
Keep You Chin UP!
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Tom Gallagher
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G'DAY SOUL PLAYER. HAVE YOU TRIDED CHANGEING THE WATERPUMP PULLY TO A SMALLER O.D. THIS WILL HELP WITH AIR FOLW.MY 67 SKYLARK 340 HAD A 1-1 RATIO AND BY DECREASING THE WATERPUMP PULLY SIZE TO 2-1 IT HELPED ALOT. JUST A THOURT! ICE-MAN
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