50 years without complete overhaul

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Dan Thomas

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Car engines have the same corrosion problem. The difference is a car is treated like a baby if it’s an old original. The cam and cylinders have rust and is grinding away too. The difference is the car is on parade while an airplane had to perform as new. A 20,000 mile 58 Olds(got an A&P buddy that owns one, one family) has its value in being 20,000 miles. It’s just starting up enough to back off the trailer and back on at a car show. If it was going to make repeated LA to NY trips, it is not going to make it without attention.
Yup. Just try running it on the highway in the Rockies pulling a travel trailer...........
 

PMD

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That is a very common thing in airplane engines...but what about cars??? Car engines are very similar in that all the parts of the camshaft, lifters, cylinder barrels, and piston rings are the exact same material.

Anybody store a VW Bug in a metal storage shed for years??? How did the engine fare?
We gave our eldest daughter a VW Golf to start University. I built a mild performance engine (big bore, G grind cam, headers, CIS, port and polish) and it went the 10 miles from our home to campus every day until early winter - when she slid into a curb. Had to park it until time to work on it. When I pulled it into the shop next spring, noticed a LOT of brown sludge on oil filler cap so pulled the cam cover (SOHC engine) only to find the brand new G grind cam nothing but one big, rusty ball of sludge. She never had the chance to run the car long enough to properly seat the rings is what I suspect. A car driven every day will simply dilute the oil with fuel and collect water until it finally gets run long and hard enough to purge. It is parking after these short runs that causes the problem - i.e. EXACTLY what a ground run duplicates.

I have built literally hundreds of air cooled VWs and never encountered anywhere near that amount of engine corrosion (but some minor evidence in several). Part of the magic of air cooled VWs (especially the earlier ones) is that just to get out of their own way, they were driven a full throttle most of the time - thus got warm quickly. In winter, if you DIDN'T beat the crap out of it there wouldn't be enough cooling air to heat the interior (same problem with Corvairs, but a lot more power to move a lot more car). Another car-to-plane difference: the airplane has a LOT of oil for an engine that will use very little horsepower on a ground run. The small sump capacity of cars will will warm much more quickly that the very large capacity of an aircraft engine.
 
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Jimboagogo

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I completely understand that when engines sit for a long time that the internal parts will corrode and the cam can begin corrode and little rust flecks chip off and get ground up between the camshaft face and lifter and the camshaft starts spalling.

That is a very common thing in airplane engines...but what about cars??? Car engines are very similar in that all the parts of the camshaft, lifters, cylinder barrels, and piston rings are the exact same material.

You often see the typical ad that reads "1958 Oldsmobile with only 20,000 miles on the clock and runs like new" and everybody gets excited.

Cars have been around forever and in the car world there has never been "CamGuard" over the decades (it is being advertised now) verses airplanes have been using CamGuard oil supplement for decades.

The camshaft of a typical OldsMoBuickChevy is located way up high on the engine and all the lifter faces get is splash oil that drips down from the rocker covers way up high...The Continental engines have the camshaft installed below the crankshaft so it gets oil that splashes down from the crankshaft above so that is an improvement over the typical V-8...the LycoSaurus on the other hand is in big trouble in that it has the exact same camshaft design but it is installed at the very top of the engine so no splash whatsoever from any oil from above so it can only be lubricated when some stray drops of oil get splashed up from the crankshaft way down below so I can see the problem with that design.

Airplane people say the problem is because of the water vapor produced when the engine is running and that is very true...but do not cars burn the same fuel and the same air so they get the same water vapor.

Airplane people also point to the big open crankcase breather letting in outside moist air...but car engines back in the 50's had the same big open breather until someone came out with the PCV valve...always wondered why airplane engines did not adopt that little contraption...sure does a good job of positive crankcase ventilating on cars and would certainly keep the bellies of our airplanes cleaner than our current Plan A...

So with car people the thought process is "wow low miles in all of these years how great" however with airplane people it is "wow low time in all of these years run for the hills".

Is it because airplane engines sleep in metal hangars that have drastic temperature changes each day and the temp swings are amplified by the fact that airplane engines use aluminum cooling fins that cause the engine also have drastic temperature changes and draw in more air at night when the hangar is cold and then breath out more air in the day when the hangar gets super hot and the cooling fins transfer the heat to the engine. Most cars have heavy iron engine blocks so the temp swings are not as drastic and most cars sleep in relatively insulated garages...

Anybody store a VW Bug in a metal storage shed for years??? How did the engine fare?
Car guys are notorious for brand loyalty. Hear me out on this one. We were in a coffee shop and overheard this guy talking about his Ford Whatever. Never had a problem, worked perfectly, never any problems. Buddy asks a question I couldn't hear, but guy says, oh they replaced the transmission for me after I complained but never had a problem... Aircraft guys simply don't have the liberty to ignore or be oblivious to mechanical issues, our consequences are more evident.
 

Pops

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We gave our eldest daughter a VW Golf to start University. I built a mild performance engine (big bore, G grind cam, headers, CIS, port and polish) and it went the 10 miles from our home to campus every day until early winter - when she slid into a curb. Had to park it until time to work on it. When I pulled it into the shop next spring, noticed a LOT of brown sludge on oil filler cap so pulled the cam cover (SOHC engine) only to find the brand new G grind cam nothing but one big, rusty ball of sludge. She never had the chance to run the car long enough to properly seat the rings is what I suspect. A car driven every day will simply dilute the oil with fuel and collect water until it finally gets run long and hard enough to purge. It is parking after these short runs that causes the problem - i.e. EXACTLY what a ground run duplicates.

I have built literally hundreds of air cooled VWs and never encountered anywhere near that amount of engine corrosion (but some minor evidence in several). Part of the magic of air cooled VWs (especially the earlier ones) is that just to get out of their own way, they were driven a full throttle most of the time - thus got warm quickly. In winter, if you DIDN'T beat the crap out of it there wouldn't be enough cooling air to heat the interior (same problem with Corvairs, but a lot more power to move a lot more car). Another car-to-plane difference: the airplane has a LOT of oil for an engine that will use very little horsepower on a ground run. The small sump capacity of cars will will warm much more quickly that the very large capacity of an aircraft engine.
I bought a new 1969 VW Bettle for $1868 delivered to my drivway. Salesman told me to shift gears on the red marks on the speedometer and to not baby it with low RPM's like driving a V8. I put 78K miles on it in 18 months were my job required being on the road a lot. Get on the interstate and put it to the floor and keep it there until an off ramp.
Good friend bought a new 1963 and would drive it from PA to TX and back to visit family the same way, WOT.
 
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Dan Thomas

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We gave our eldest daughter a VW Golf to start University. I built a mild performance engine (big bore, G grind cam, headers, CIS, port and polish) and it went the 10 miles from our home to campus every day until early winter - when she slid into a curb. Had to park it until time to work on it. When I pulled it into the shop next spring, noticed a LOT of brown sludge on oil filler cap so pulled the cam cover (SOHC engine) only to find the brand new G grind cam nothing but one big, rusty ball of sludge. She never had the chance to run the car long enough to properly seat the rings is what I suspect. A car driven every day will simply dilute the oil with fuel and collect water until it finally gets run long and hard enough to purge. It is parking after these short runs that causes the problem - i.e. EXACTLY what a ground run duplicates.
I had a 1974 Ford Courier. Bought it in '75 with 2500 miles on it. Drove it for seven years, up to 104,000, and it was the best vehicle (mechanically) that I ever owned. Made by Mazda. Long after it was broken in it would still have milky crud in the rocker cover, which had to come off every 10K or so to adjust the valve lash. Was driving ten minutes to work, mostly. It never got warm enough to drive the water off doing that. And that was with a PCV system, too. Compression was good, didn't use oil. Occasional longer trips are what saved it.

In the flight school we'd pull the dipstick on an airplane that had just come in from a flight in very cold weather (our limit was -25°C, or about -13°F). We'd often see the milky oil on it. Oil cooler blocking plates were the cure for that. If we had flown an airplane like that only once a month, the engines would have been shot in 100 hours. Water gets into the case, mixes with the oil, and in the presence of the metals in the engine to catalyze the mix, forms acids that eat the engine. From the inside. Sulfuric, hydrochloric and nitric acids. Yum. Oxygen and hydrogen from the water, plus sulfur and chlorine and nitrogen from the oil.

Older cars suffered this, too. The guys that were old when I was young had grown up driving real cars---you know, the ones where you had to do most of your own maintenance and had to know how to operate a choke and spark advance and all the rest. They knew about engine corrosion, and some of them would mix a bit of baking soda with some oil and dump it into the engine in between oil changes, and that engine would last forever. At a time when 100,000 miles meant that the car was a rattling wreck, those old guys ran their cars, on the original engines, for 300,000 or more. The soda would neutralize the acids.

PCV fixed most of that. Airplanes are still stuck with it. There are ways to make it worse: Using a crankcase breather oil separator is one; it gets the oil out of the air leaving the breather so as to keep the belly clean, and returns it to the engine. Problem, of course, is that it also returns water and acids to the engine. The other is to use an oil sump heater, which heats the crankcase and the oil, and doing that raises the vapor pressure of any water so that it evaporates and then cools and condenses elsewhere such as on the camshaft and lifters. and exposed cylinder walls. Ground-running the engine contributes mightily to that. If you're going to use an engine heater, use it and then fly it right away. Don't leave it warming the engine for days.
 

Pops

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Bought my first car that had 23k miles on it. 1953 Ford 2dr sedan. Looked and ran like new. Last year of the flathead engine. At 9 years old and 103K miles it was burning 20 miles to a quart of oil and was a bug duster. Floors rusted out and had to drive with the windows down for the oil smoke even in the winter in Western PA. No one tailgated. Stop and get $1 of gas at 19 cents a gallon and take the 2 gal can of the .49 cents a can oil out of the trunk and top it off with oil.
The good old days.
 

PMD

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They knew about engine corrosion, and some of them would mix a bit of baking soda with some oil and dump it into the engine in between oil changes, and that engine would last forever. At a time when 100,000 miles meant that the car was a rattling wreck, those old guys ran their cars, on the original engines, for 300,000 or more. The soda would neutralize the acids.

The other is to use an oil sump heater, which heats the crankcase and the oil,
Lube oils contain inhibitors to neutralize corrosive compounds, but as one might expect, they are insufficient for a big wad of brown sludge - as is reality for short trip, cold weather driving.

I STRONGLY advise for oil heaters in just about everything, but problem is: few if any people design their engines with accommodations for a proper submerged heater or even a thermo-well to accept element without risk of leakage on failure. The fancy full synth oils (that I also strongly endorse) may have incredible VI and flow like a darn at minus oh-shyte but that doesn't do anything for the water and fuel dillution that everything suffers in cold/short drives.
 

TFF

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We always used a small space heater set in the cowl. Heating the oil make the vapor rise to a cooler part of the engine. We would be warming all the engine so the vapor did not condense as it moved around. As the G&N head engine guy said of sump heaters, makes a great terrarium.
 

PMD

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We always used a small space heater set in the cowl. Heating the oil make the vapor rise to a cooler part of the engine. We would be warming all the engine so the vapor did not condense as it moved around. As the G&N head engine guy said of sump heaters, makes a great terrarium.
I should have mentioned that I expect to have a properly insulated winter cover to deal with that. We used to use interior car warmers (that have a circulating fan) strapped to motor mount with Adel clamps, but technically not legal (blind eye from MoT) and 850 watts would warm the engine, oil and battery just fine at -40 or more. I think the same amount divided between oil sump and water jacket with proper cowling (and maybe a 50 watt battery pad) would do the job right. But again, it is the very tight, well insulated cover that delivers the coup de gras to moisture.
 

Pops

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I was given a VW gasoline powered heater that set over the fuel tank under the hood of the VW bug. I converted it to propane. It has a 6 volt ignition system for the spark plug, same are the car and the points is mounted at the rear of the 6 volt blower motor. I happen to have a large 110 volt to 6 volt transformer and made a full wave rectifier for a 6 volt DC for the heater and powered it with the 110 AC grid electric in the hanger. It would heat a small house. I also made a grill over the exhaust pipe for heating food. It the winter I heated the hanger to a comfortable level when working on the Cherokee. I also had a 6" flex duct to under the air outlet in the cowl and put a thick blanket over the cowl. It the winter, heat something hot to drink and with the cabin heat on the cabin would be as warm as the engine of the Cherokee. Finish your drink and go flying.
 
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PMD

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I was given a VW gasoline powered heater that set over the fuel tank under the hood of the VW bug. I converted it to propane. It has a 6 volt ignition system for the spark plug, same are the car and the points is mounted at the rear of the 6 volt blower motor. I happen to have a large 110 volt to 6 volt transformer and made a full wave rectifier for a 6 volt DC for the heater and powered it with the 110 AC grid electric in the hanger. It would heat a small house. I also made a grill over the exhaust pipe for heating food. It the winter I heated the hanger to a comfortable level when working on the Cherokee. I also had a 6" flex duct to under the air outlet in the cowl and put a thick blanket over the cowl. It the winter, heat something hot to drink and with the cabin heat on the cabin would be as warm as the engine of the Cherokee. Finish you drink and go flying.
In 6 volt days up here, we got the South Wind US made heaters (very similar to what is used in airplanes). Our first German heaters came with 12V cars - Eberspacher B2. I believe those existed in 6V days, but strangely we did not get them in the Great White North. Later cars had in-duct Webastos (IIRC '68/'69) that were so bad VW replaced them all under goodwill warranty with BN2s. The biggest heaters came in the Type IIs - and they had fantastic output.. Sorry for the wandering down memory lane, but that all gets back to my 1970 type III wagon. It had a BN2 and for nights when my airplane wasn't plugged in I put a 4" Tee and cap in the duct to the interior and would use a silicone hose to send that wonderful HOT air into the engine room while I sat in the toasty warm car and watched the world go by.

To bring that home to HBA: our own Craftsven had witnessed such craziness on our ramp and designed and started series manufacture of a similar size profane fueled, all SS heater that he made in both 12VDC and 120VAC models. Sold a mess of them, and I think still in production somewhere down East. Intended for aircraft, but useful in so many ways. Ultra portable.
 

robertl

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I bought a new 1969 VW Bettle for $1868 delivered to my drivway. Salesman told me to shift gears on the red marks on the speedometer and to not baby it with low RPM's like driving a V8. I put 78K miles on it in 18 months were my job required being on the road a lot. Get on the interstate and put it to the floor and keep it there until an off ramp.
Good friend bought a new 1963 and would drive it from PA to TX and back to visit family the same way, WOT.
I had a VW Bug back in the 70's and a German guy I worked with said to red line it in every gear for best results. I kept the valves adjusted and drove the holy crap out of it and never had any problems, I guess he knew what he was talking about.
Bob
 

Pops

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The red marks on the speedometer are the recommended shift rpm's. I think the rpm's at the red marks are about 3K. Just a guess. Also I think it was in 1968 or 69 models that started the shift red marks.
 

MaydayMayday

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Good information...thanks! Larger quantity of oil in the airplane engine verses much less quantity of oil in an air cooled car engine is a big factor that I did not consider. Takes a lot to heat up that much oil. Never going to do that doing ground runs.

The car engine has a thermostat so even idling the engine the operating temp of 180 - 210 coolant temperature is much warmer that the air cooled airplane engine so the inside of the engine where the oil is splashing around gets hot enough to steam off the water vapor way more than the air-cooled airplane engine.

Sorry that I hijacked the original thread.
 

challenger_II

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Rule of thumb, for aero, and auto, engines:

"Bring the engine up to Operating Temperature, or above 180 degrees oil temp, for no less than 30 minutes, to reduce trapped water vapor in oil supply."

Old Phart Round Engine mechanic hammered that into my head. He spent a considerable amount of time in the Aleutians during the comparatively recent Unpleasantness with the Japanese.
 

challenger_II

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Sometimes, hijacking is beneficial: look at how much useful information was presented because of your "hijacking"...

Good information...thanks! Larger quantity of oil in the airplane engine verses much less quantity of oil in an air cooled car engine is a big factor that I did not consider. Takes a lot to heat up that much oil. Never going to do that doing ground runs.

The car engine has a thermostat so even idling the engine the operating temp of 180 - 210 coolant temperature is much warmer that the air cooled airplane engine so the inside of the engine where the oil is splashing around gets hot enough to steam off the water vapor way more than the air-cooled airplane engine.

Sorry that I hijacked the original thread.
 

Dan Thomas

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I should have mentioned that I expect to have a properly insulated winter cover to deal with that. We used to use interior car warmers (that have a circulating fan) strapped to motor mount with Adel clamps, but technically not legal (blind eye from MoT) and 850 watts would warm the engine, oil and battery just fine at -40 or more. I think the same amount divided between oil sump and water jacket with proper cowling (and maybe a 50 watt battery pad) would do the job right. But again, it is the very tight, well insulated cover that delivers the coup de gras to moisture.
Also I think it was in 1968 or 69 models that started the shift red marks.
My '62 Beetle had little shift marks on the speedometer. Long time ago (50 years) and I can't remember their color.
 

Dan Thomas

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Good information...thanks! Larger quantity of oil in the airplane engine verses much less quantity of oil in an air cooled car engine is a big factor that I did not consider. Takes a lot to heat up that much oil. Never going to do that doing ground runs.

The car engine has a thermostat so even idling the engine the operating temp of 180 - 210 coolant temperature is much warmer that the air cooled airplane engine so the inside of the engine where the oil is splashing around gets hot enough to steam off the water vapor way more than the air-cooled airplane engine.

Sorry that I hijacked the original thread.
The aircraft engine's cylinder head temps will get really hot in a ground run at higher RPMs, long before the oil gets to any worthwhile temperature. That limits the ground run time and power level. The aircooled aircraft engine has no thermostat, and when sitting still on the ground the only cooling air it gets is whatever the inboard section of the prop manages to stuff into the cowl. If it's not pointed into the wind, it's a lot worse. It's designed to fly.
 
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