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What to do if engine overheats at freeway speeds??

In the middle of a trip, my engine temp at the cylinder head started approaching 375 degrees, after a number of steep hills. Did not know the best approach to get the temp back down. Possible solutions:

  1. Slow down to 50 MPH in the slow lane of a freeway and stay in fourth?
  2. Slow down even more, and shift to 3rd, bringing the RPM up?...and risk getting rammed from behind,
  3. Pull over at an exit, stop and turn off engine?
  4. Pull over at an exit, keep engine running, transmission in neutral, and raise RPMs (e.g. to 2,000) to keep the fan going very fast?
Reply to
Emily Steed
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Pull over & stop, while your stopped put the engine tin back on then you won't have to worry about over heating again. As long as you have the tin on & you are not low on oil you should not over heat. I know guys that drive in 105+ degree heat all day long that don't over heat.

Jim

Reply to
Fred Kat

Depends on the engine in question... if it was "rebuilt" and or adjusted wrong, it will overheat no matter what...

Jan

Fred Kat wrote:

Reply to
Jan Andersson

#1.

A steep hill reprsents an increased load on the engine. The greater the load, the more fuel you must burn to maintain the same speed. The more fuel you burn, the more waste heat to be gotten rid of. The only problem here is that the VW doesn't have a lot of fin area on its heads, wasn't really designed for high levels of output.

The nominal output of the VW engine is only about 15bhp. Demand more from the engine, the CHT will rise. You may continue to run at an elevated CHT if you wish but doing so will shorten the useful life of the engine, dictate the need for more frequent oil changes and other periodic maintenance.

Just pull your foot out, run with the trucks. The difference in travel time is quite small but you'll realize a dramatic reduction in fuel consumption & maintenance costs, plus the thing lasts longer.

-Bob Hoover

Reply to
Bob Hoover

so it is better to keep the car moving (at a slower speed) rather than pulling over and either shut off the engine, or pulling over and revving the engine at about 1,500 RPM to let the fan cool off the engine??

Reply to
Emily Steed

Don't worry, 375 degrees F is not hot for an aircooled cylinder head. I would worry when it nears 450 degrees F. If it nears 450 deg F, you need to slow down and increase fan speed, IE downshift. It is also possible that your cylinder head temp gauge is calibrated wrong so that it reads the ambient tempurature PLUS the cylinder head temp. This would place the cylinder heads at around 310 degrees F probably, which is practically cold.

~Anthony

Reply to
Anthony

******* If you start to loose power then you should definately cool it down; I would think stopping & running at a "fast idle" would be best. That would remove all the load & increase the amount of air flow... Also, double check your timming, jets, etc. to find out why it's running hot. ~ Paul aka "Tha Driver"

Giggle Cream - it makes dessert *funny*!

Reply to
ThaDriver

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Yes, so long as the conditions are as you described, ie, the CHT is 'approaching 375.' That is just within the yellow arc; the engine is telling you to slow down, that the outside air temperature and/or the load on the engine is producing more waste heat than it can get rid of.

Common sense also plays a role here. I have to assume you have your normal share; that the vehicle is in reasonably good condition, that you understand its limitations and so forth. The air cooled Volkswagen is an antique. Unlike modern vehicles in which the engine's computerized controller does most of the thinking for you the VW is NOT a transportation appliance. If you expect maximum service life from the engine it must be operated strictly within its capabilities.

-Bob Hoover

Reply to
Bob Hoover

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