Aircooled VW oil Synthetic?

[foppert]

Hi all, I am working on fixing up my aircooled vw that has been sitting for about 5 or so years. I always used to run zr1 sae30 in it, but that has become nearly impossible to find in my area.

Looking for a new option, reading around it seems like alot of myths around aircooled oil and synthetics not cooling properly are still around (or are true?)

I run Supertech synthetic in my other jalopies, would 10-40 Supertech synthetic be about right for it? or would I be better off with a diesel oil?

 

[Propflux01]

That old Gene Berg myth about synthetics not cooling properly or as much is just that...myth. I always used a 10w-30 in mine, of course, they were equipped with all components of the cooling system, flaps, thermostat, etc. The 10w-40 would work ok in it, as would any 15w-40 "diesel" oil.

 

[berniedd]

In the '70s I used regular dino oil 15W-40 in my 1968 VW. Often it was diesel engine oil. Many years later, occasionally used semi syn when it became more available and lower priced. Always used regular fuel bec it was not a high compression engine (7.5:1 IIRC). In 1994 it got fitted with aftermarket airconditioning and a cooling system upgrade (doghouse oil cooler and thicker fan), and I shifted to 91 octane gas to keep up with the higher engine load.

 

[foppert]

I'm leaning towards the supertech 15-40 full synthetic, dirt cheap and probably better than any oil these engines were ever designed for, high zinc too.

Thread 'New Super Tech 15w-40 CK-4/SN Full Synthetic HDEO VOA w/PC'

May 10, 2024

This is an HDEO from Walmart SuperTech brand that is now offered in a Full Synthetic. Here is the VOA w/Particle Counts.

• fantastic
• hdeo 15w-40 supertech 15w-40 supertech diesel oil
• Replies: 96
• Forum: Virgin Oil Analysis - PCMO/HDEO

• 
• 
• 

This particular VW has been punched up to 1.9L and always would always run noticeably perkier with higher octane, when gas was really expensive I always pulled a bit of timing to accept 87 a bit better.

Some unrelated to oil background:
For waking this VW up I'm going to change the motor oil and try and mist some mystery oil into the spark plug holes and crank it over without the plugs a bit to spread the fresh oil around. 5-6 years the longest this car has ever sat, I tried to start it a year or two ago and found a bunch of bad fuel lines/clogged carbs. Carbs are rebuilt now and i replaced all the fuel lines so we should be good to go. Its been garaged the whole time so hopefully not too much degradation/corrosion.

 

[Propflux01]

I'm leaning towards the supertech 15-40 full synthetic, dirt cheap and probably better than any oil these engines were ever designed for, high zinc too.

Thread 'New Super Tech 15w-40 CK-4/SN Full Synthetic HDEO VOA w/PC'

May 10, 2024

This is an HDEO from Walmart SuperTech brand that is now offered in a Full Synthetic. Here is the VOA w/Particle Counts.

• fantastic
• hdeo 15w-40 supertech 15w-40 supertech diesel oil
• Replies: 96
• Forum: Virgin Oil Analysis - PCMO/HDEO

• 
• 
• 

This particular VW has been punched up to 1.9L and always would always run noticeably perkier with higher octane, when gas was really expensive I always pulled a bit of timing to accept 87 a bit better.

Some unrelated to oil background:
For waking this VW up I'm going to change the motor oil and try and mist some mystery oil into the spark plug holes and crank it over without the plugs a bit to spread the fresh oil around. 5-6 years the longest this car has ever sat, I tried to start it a year or two ago and found a bunch of bad fuel lines/clogged carbs. Carbs are rebuilt now and i replaced all the fuel lines so we should be good to go. Its been garaged the whole time so hopefully not too much degradation/corrosion.

If you don't already know, put your fuel filter before the pump, not after it!

 

[JavierH19]

You can use pretty much anything in it. I'd use 15w-40.

 

[vwmaniaman]

I use 30 at dino in my 1965 bug with 1600 single port motor. You may want to use high mileage to soften those old hard rubber seals.

 

[drtyler]

Rotella T1 SAE 30 at Walmart; $18 for gallon. Back of the jug states API SL rating, so it is approved for use in your gasoline engine. I typically use this oil or VR1 SAE 30 in my VW aircooled engines.

https://www.walmart.com/ip/Shell-Ro...l-Motor-Oil-1-Gallon-API-CF-2-CF-SL/958899660

VR1 10W-30 in 5 quart jug is available at Walmart for $27, on the shelf or online:
https://www.walmart.com/ip/Valvoline-VR1-Racing-10W-30-Motor-Oil-5-QT/5089154508

Amazon has the 6 quart case of VR1 SAE 30 for $45, shipped free:

https://www.amazon.com/Valvoline-SAE-VR1-Racing-Motor/dp/B00DJ4FOFA/

 

[foppert]

hmmm, The Rotella sae30 is a good choice.

I watched a YouTube bit on this that showed VW Mexico suggested 15-40 in 2003, and Porsche sells a 20-50 for their vintage aircooleds currently.

I think the multi weight might be the way to go.

 

[brandon9715]

After seeing the difference in synthetic oil in my Sportster years ago, I only run synthetic oils in air cooled engines, regardless of age. My oil temp dropped 30-40 degrees F switching from a synthetic blend to a full synthetic.

 

[berniedd]

.... and always would always run noticeably perkier with higher octane, when gas was really expensive I always pulled a bit of timing to accept 87 a bit better.

5-6 years the longest this car has ever sat, I tried to start it a year or two ago and found a bunch of bad fuel lines/clogged carbs. Carbs are rebuilt now and i replaced all the fuel lines so we should be good to go. Its been garaged the whole time so hopefully not too much degradation/corrosion.

This has been my experience as well. Moving up to 91 octane was a good move. I used to start my "stored" VW once every 3 weeks in the early 2000s till the battery died. It sat 5 months, and after I got the battery changed it would not start. I didn't know it at the time but the E10 would degrade and turn into mush. Found out the hard way. Had to disassemble the carb. Found the mush inside the float chamber and saw a powdery deposit too which seemed to be due to a corrosion effect in the aluminum walls. The fuel line from the gas tank up front to the engine in the rear was clogged too. Got to free it with compressed air blown from the rear end of the line.

 

[oil pan 4]

When that engine was designed motor oil didn't even have additives or barely had any additives. The closes thing to what you were using is probably Walmart 30wt cd2 off road diesel oil.
How hot does the oil get? That should be your starting point of what viscosity to use, shoot for 10cSt or more at operating temperature.

 

[wings&wheels]

I'd run M1 15w-50 or M1 V Twin 20w-50 assuming no real cold weather use. Excellent oils with appropriate additive levels for older motors. As noted Porsche recommends syns in various weights for their air coolers and I have run syns in all of my old toys for as long as I've had them without any issue.

 

[Marrk]

My air cooled engines were all motorcycles, not cars. I used Castrol dino in the '70s, but I do not remember what I used when synthetic became available. It really doesn't matter. What matters is the appropriate weight and the OCI. The only caveat would be on a rebuild. Then, you might want a dino oil in order to let the rings seat.

Note: I'm not an oil expert. That's why I'm on bobistheoilguy.


EDIT: Maybe it does matter on VWs. Maybe it does matter on flat-4s. I have no idea. Others here will probably know.

 

[High Performance Lubricants]

Viscometrically a 10W50 or 15W50 provided they are shear stable. Chemically API SL.

 

[OilStainedNapkin]

I’d go with any flavor of supertech. Fantastic oil at a fantastic value

 

[addyguy]

Any of the full-syn 15W-40’s would be just about perfect for this application.

 

[Zack1978]

I use Amsoil Z Rod in my air-cooled VW, I think I have 10w30 in there now.

 

[Chris142]

My dad had 2 bugs. A 70 and a 74 super. He ran Pennzoil 10w40 in them. Both went well over 100k with no major repairs. I remember the 74 had 145k on it when he wrecked it. I think the 70 was @120k when he parked it for no good reason.

 

[berniedd]

After seeing the difference in synthetic oil in my Sportster years ago, I only run synthetic oils in air cooled engines, regardless of age. My oil temp dropped 30-40 degrees F switching from a synthetic blend to a full synthetic.

That is an impressive drop in oil temps. Considering that syn blend oil is likely anywhere between 55%-80% dino oil makeup and 20% - 45% syn oil.