ablessedbugowner
Since I am a new Bug owner, I have what you might think is a silly question. I noticed that my engine was running pretty hot today - I live in West Texas and the temp was over 100 F this afternoon. I have about a 25 mile trip home. When I got home, the engine had some smoke coming from it. Any ideas on how to keep it cooler? I was reading up on the air flap and thermostat but no where have I been able to find anything that tells me where these are. I have a 72 Super Beetle. I'm new at all this and so I was hoping to find a good picture showing where too look.

Thanks
'72 Super Beetle
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olspeed
Time to crawl on the ground, look under the car at the engine (passengers side) there should be a bracket that bolts to the side of the engine. it will be covered by the cooling tin, but by looking from the back forward you should see it on that side. remove the four bolts that hold the tin on the bottom on that side and you will see the bracket and thermostat bellows(if it's still there). As designed by VW the air control flaps should stay open if the bellows fails but as with any 30+ year old car things may not be working like they should. loosen the bolt holding the bracket to the engine block and it should spring up toward the engine(work with the engine stone cold) if not the flaps are stuck or the spring is broke and you will have to pull the fan shroud to find and fix the problem. If it does spring up then here is what the VW Service Manual says to adjust it. (section 1  engine  subsection 6.1  page 14)
1. If a new thermostat is being installed,screw it onto the thermostat rod. If the adjustment is simply being checked,unbolt the thermostat from it's bracket.
2. raise the thermostat off its bracket until the control flaps are wide open. if the top of the thermostat does not just contact the upper part of the bracket an adjustment is required.
3. To adjust, loosen the mounting nut that holds the bracket on the case. then move the bracket (up or down) until the upper part of the bracket just contacts the top of the thermostat with the thermostat raised to open the control flaps fully.
4. Lock the bracket in position by tightening the nut.
5. Pull the thermostat down and bolt it onto the lower part of the bracket.
Sorry about no pictures as I don't have a scanner,but if you look under the car it should be pretty self explanatory.
Olspeed


 

66 Ghia 76 std Beetle
It's not a car it's a VolksWagon
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MY72BUG
Some other things to ponder when an air-cooled engine is running too hot:
 Is all of your engine tin in place?  I see it all the time at car shows where the engine compartment seals are missing, tin has been left off etc.  One serious offender is the tin at the front of the engine ( against the "hump") missing.  This does not improve cooling it instead allows you to vacuum road dirt and garbage off of the street - a great disservice to your engine.  A guy I know up here had a chronically overheating engine.  This tin piece was missing and that handy oil wiping rag which he kept under the engine cover had been sucked into the cooling fan along with a shopping bag !  I yoinked all of that crap out of there and he replaced the tin.  Voila - a happy engine.  What are you using for oil?  In the heat you experience down there, 30W-50 would be advised and I would lean toward removal of the thermostat altogether and wiring open the lever for the cooling louvres.  This is a subject which gets kicked around a lot.  My experience, and this is Southern Ontario, Canada with a summer only driven car, is that if you do  a patient driveway warm up at idle, a thermostat is not needed.

I'd rather have a partial bottle in front of me than a partial frontal lobotomy.
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ablessedbugowner
Thanks, I did notice that the hot air heater hoses were missing. I added those back on and yesterday it was a lot better.

I'll probably crawl under the car this weekend to look at the other things ya'll mentioned.
'72 Super Beetle
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olspeed
On the thermostat and flaps, I know that there is a on going debate as to whether or not you need them. This is my point of view. First off a VW engine although air cooled is still an internal combustion engine,thus you still get the same contaminants in the oil that you would get on a water cooled engine... IE.water and acids from combustion,these are not completely removed by an oil filter, especially the screen on a stock VW. You would not remove the thermostat from your new BMW or Chevy or what ever and expect it to have clean oil after driving it. This is especially important if you do more city driving than long trips. Also just think about it, just as the thermostat in a water cooled car cycles on and off to keep the temperature at it's set range so does the bellows thermostat in the VW engine,as the engine comes up to running temperature the thermostat opens to let more air(water) through and it will close up if the temperature drops below the preset range. The idea with both the air cooled and water cooled versions is to warm up quickly and keep the engine at it's optimum temperature all the time.Thermostats do not just open and then stay open they cycle open and closed, air or water I have seen this when dyno'ing engines and checking the water temp before and after the thermostat housing with a heat gun, you can watch the temperature rise and fall as the thermostat opens and closes.This keeps the engine itself a it's normal temp, range. Also on the air-cooled engine ALL of the tin work needs to be in place for things to work properly,I have seen a lot of engines that have the bottom deflectors removed to get to leaking push rod tubes and then not replaced. This causes the thermostat not to work properly and keep the flaps closed when they should be open. So and as I said this is my opinion, the stock cooling tin and thermostat are important and should be kept in place to have a reliable and long lasting engine.
Olspeed
66 Ghia 76 std Beetle
It's not a car it's a VolksWagon
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jaygyver
Also, The heater hoses should always be hooked up to the stock Exhaust heater boxes as the flap on the front of the exhaust box either lets the air into the interior or dumps the air outside to cool the "closed" exhaust, so if the hoses aren't hooked up to the the heater boxes then there is no air to cool the exhaust pipe. Air goes through the heater boxes ALL the time. You just change where it goes.
Think of the exhaust pipe as a heat sink. With the exhaust enclosed, there is no air to cool the pipe like a "J" pipe would with the outside air cooling it.
The engine bay is under NEGATIVE pressure with the cooling fan and carbs sucking away, so it will draw any air from ANY hole, hot or cold. Do a quick look and see if you can find any bad seals or unplugged holes.

Another thing to think about on the Thermostat is, 100 F is hot to you, but pretty much ANY car engine oil is designed to run at about 185F (+-) to lube and burn any contaminants off (acids, ash, moisture etc.) in a perfect world. The biggest thing the Thermostat does is control the warm up time and then control the temperature. The thermostat flap "housing" has a set of "Static" mounted flaps (does not move) that direct the air to where it's needed most. The cylinder and head warm up at a different rate. It's more for longevity. From what i understand 90% of all wear on any vehicle is in the start up/ warm up period.
If your thermostat did die then at least just wire OPEN the flaps, as the thermostat is the only thing that opens them.
Being there in Texas it's not that big a deal as up in the cooler climates. A lot of people use the thermostat and a lot don't. Your call.
'72 and '75 Super Beetle's
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vwrod

Where is a good source for a replacement thermostat?

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olspeed

Gene Berg use to sell them, but my catalog is quite a few years old so you will have to check them out at geneberg.com I am sure that you could be able to find a good used one at most of the vendors that sell used parts.Also are you sure that yours is bad. The VW thermostat is a bellows type set up. When it goes bad it will expand to it's full length as though it was heated, if it is still in it's collapsed state (completely pulled together) then it should still be good.

Olspeed

66 Ghia 76 std Beetle
It's not a car it's a VolksWagon
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vwrod

It's expanded.

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