Can Too Much Oil Damage Your Motor?, Mechanic Added Too Much Options

[windforfun]

Ran it for about 1 hr prior to draining excess oil. The motor is a "73 1.7. Thanks.

[emerygt350]

I do notice some different behavior as far as oil temp and pressure depending on filter. I mean, it is the most critical health component of these engines so a little attention here goes a long way for longevity, Particularly when you race it.

[Superhawk996]

I do notice some different behavior as far as oil temp and pressure depending on filter. I mean, it is the most critical health component of these engines so a little attention here goes a long way for longevity, Particularly when you race it.

I was being playful but realize my flippant response may have come across as me being an (IMG:style_emoticons/default/bootyshake.gif) clown.

We can do a whole dissertation on Tribology. There are engineers that do only Tribology for their whole career.

Here's the thing. Keep you oil & filter changed regularly (let's just go with the old 3,000 miles myth) on an air cooled engine and life will be good - generally speaking.

On temperature -- temperature and viscosity go hand in hand. Use multi viscosity oil to help offset the effect.

To dig deeper, an oil filter really does nothing for you w.r.t racing. It will catch chunks -- that's about it. If you're seriously taxing your oil, change it every race if need be. The most important thing that you can do for any engine is to have the bearing clearances set properly when the engine is built - race engine or otherwise. Here's the thing about pro racing, the engine only needs to last one race.

With respect to filter size -- fill oil, start car, shut down car, let sit a couple minutes, then recheck oil level. Once the oil filter has filled with oil, and you recheck the oil level, the size of the filter become irrelevant. It could be 1 pint, or 1 gallon, you would accommodate the volume lost from the sump to the filter on the recheck.

With respect to oil pressure loss across various filter brands -- Yup - it's true. Lower filtration efficiency = lower pressure loss (generally speaking).

We could go on about oil & all the nuances. That is what I was joking about.

But the bottom line is -- don't make this too hard. Fill with oil (to mark on dipstick), go drive (IMG:style_emoticons/default/driving.gif)

And to address OP question on over fill . . . . if it is overfilled, drain some. You did the right thing (IMG:style_emoticons/default/smilie_pokal.gif) Yet another good reason to do maintenance yourself . . . the world if full of dopes (IMG:style_emoticons/default/slap.gif) . . .. including me.

[bbrock]

Here's the thing. Keep you oil & filter changed regularly (let's just go with the old 3,000 miles myth) on an air cooled engine and life will be good - generally speaking.

Can you elaborate on this? I'm getting ready to do my first 3,000 mile oil change since rebuild which will happen regardless of answers here, but have been contemplating oil change intervals. Porsche recommended 5,000 mile oil changes with 50 year old single weight oil formulations. What's the rationale for shorter oil changes? More interesting, let's hear the myth busting. (IMG:style_emoticons/default/happy11.gif) My owner's manual says, "Under normal driving conditions it is unnecessary and uneconomical to change oil at intervals shorter than is described in the Service-Schedule of the Maintenance Record." And oil has advanced significantly over the 50 years since that was written.

[wonkipop]

Here's the thing. Keep you oil & filter changed regularly (let's just go with the old 3,000 miles myth) on an air cooled engine and life will be good - generally speaking.

Can you elaborate on this? I'm getting ready to do my first 3,000 mile oil change since rebuild which will happen regardless of answers here, but have been contemplating oil change intervals. Porsche recommended 5,000 mile oil changes with 50 year old single weight oil formulations. What's the rationale for shorter oil changes? More interesting, let's hear the myth busting. (IMG:style_emoticons/default/happy11.gif) My owner's manual says, "Under normal driving conditions it is unnecessary and uneconomical to change oil at intervals shorter than is described in the Service-Schedule of the Maintenance Record." And oil has advanced significantly over the 50 years since that was written.

back in the 60s and 70s in aus it was relatively common for folks with VWs to do oil changes at twice the recommended min intervals (5,000) VW specified. 5,000 miles was roughly twice a year for mileage in average use (and a lot of other cars besides VW had identical 5000m or twice yearly changes). 3 monthly changes were common amongst the fastidious. my mechanic back then, a german, was more specific with his views. his opinion was you had to keep the oil fresh in the australian summer. so i did roughly 3 changes. car was a daily driver. 1 at start of high summer and 1 at end then one in between. this was because oils were mineral based back then and they did break down when the engine ran hotter. and they did run hotter in summer down here. that was the reasoning.
i would have thought synthetic oils are better at not breaking down in use and can go further between changes. esp in colder winter months.

EDIT.
i should add i drove a type 3 squareback. type 3 suitcase engines were notorious for running hotter than type 1 beetles down here. so the advice from my mechanic was to an extent focussed at the type 3 specifically.

[bbrock]

i would have thought synthetic oils are better at not breaking down in use and can go further between changes. esp in colder winter months.

I've read that while synthetics don't break down as fast as conventional, they still get dirty so still should be changed at the same interval. I've always run synthetic in my cars and will do the same in the 914 after one more cycle with VR1.

Still interested to hear why @Superhawk996 calls it the "3,000 mile myth." I'm pretty sure there are some nuggets of wisdom he has to share.

[Superhawk996]

i would have thought synthetic oils are better at not breaking down in use and can go further between changes. esp in colder winter months.

I've read that while synthetics don't break down as fast as conventional, they still get dirty so still should be changed at the same interval. I've always run synthetic in my cars and will do the same in the 914 after one more cycle with VR1.

By now there is no dispute. Synthetics are superior to Dino oil.

Synthetics are superior in the following way:

Resistance to oxidation -- this is the most compelling reason to use them.

Synthetics have a more consistent Viscosity Index. This means they don't change viscosity as much as a function of temperature. DO NOT confuse this with viscosity itself (i.e. 5w20, 30W, etc.) This is a measure of viscosity stability as a function of temperature.



Again, don't believe me. In 2017 AAA did a pretty decent 3rd party assessment of the synthetic vs. conventional oil debate.

Results:



Complete study:
https://newsroom.aaa.com/wp-content/uploads...AL-EXTERNAL.pdf

I'll leave it up to debate as to whether the cost delta is "worth it".

Since synthetics are much more stable than Dino oil. Extended oil changes are possible with synthetics. How good of an idea this is depends on a lot of things like condition of the engine, cost to replace the engine, type of service (racing vs. Sunday driver), etc. It should go without saying that if you go the synthetic route, choose one with a good Zinc additive package to take care of our cams and lifters.

The main problem we face with air cooled T4 engines is that they are pretty archaic, they run hot, they suffer from high(er) combustion blow by due to the cylinder design as compared to a water pumper. So yes. . . . you'll see more carbon in your oil.

However, dark oil doesn't indicate "bad" oil with Synthetics. Again, this is some of our own superstition working against us based on what we think we know about Dino oil. Carbon blow by and build up in your oil isn't the main source of wear. What causes wear is metal to metal contact caused by oil viscosity degradation due to elevated temperatures, decreased lubricity, etc., due to things like oxidation and shear of the molecules. As previously demonstrated, Synthetics are superior at resisting these types of degradation.

So, I'll leave it to each to decide how far they wish to push the service interval if using synthetics but I'd suggest that 15,000 miles is a pretty well defined upper limit based on what other OEM's have recommended for water pumpers but I have no hard data to back this for a T4 air cooled engine.