[T3] Stupid question #395 Oil change time?

[donrob at yachtsales.com]

Lucas Oil makes oil specifically for classic cars:  
https://lucasoil.com/products/hot-rod-high-performance

I have been using it for years with no problems, in air cooled to hard 
working V8 engines, and even in a GM 250 six in a combine.

You can get your local FLAPS to order it, it is made in the USA.

Don Robertson
905 566-0000
donrob at fastmail.com




On 2019-05-28 13:45, Jim Adney wrote:
> I think there are a few basic rules we can apply to oil changes.
> 
> 1) Change it every 3000 miles, or at least once a year.
> 
> 	a) Short trips are harder on an engine, but short means too short for 
> the
> 	engine to fully warm up.
> 
> 	b) Warmup happens faster in warmer weather. 50 F may seem cool to
> 	you, but that's nothing compared to -20 F.
> 
> 	c) If you don't have the complete thermostat, linkage, and flaps,
> 	installed, you should assume that your engine NEVER warms up.
> 
> 2) If this car is going into storage for an extended time, change the
> oil first,
> so the engine sits with fresh oil, not contaminated oil.
> 
> 3) Zinc, in the form of ZDDP, used to be an essential part of any 
> engine oil,
> but it poisons catylitic converters, so it's been dropped. Cars with 
> Cat Cons
> switched to non-ZDDP oils and roller cams, so now there are few 
> standard
> oils that are good for flat tappet engines. I THINK that any oil out 
> there that
> has the API seal on the front lacks ZDDP. You might find diesel oils 
> that lack
> this seal. (This API seal has a zig-zag border and is always found on 
> the
> front of the container, not to be confused with the smooth round 
> Service
> Rating on the back.)
> 
> 	a) ZDDP is especially important during breakin of the cam. It may not
> 	matter so much in a well broken-in engine.
> 
> 	b) It sounds like GM's EOS is a good source for ZDDP.
> 
> 	c) I'd be surprised if STP had ZDDP in it, as that would make it a 
> very
> 	bad choice for any modern engines. I'll check on that later this week 
> at
> 	my FLAPS.
> 
> 4) Going to higher viscosity oils, like 20W-50 may seem like a good 
> choice,
> but that can be misleading. It takes more engine power to pump a high
> viscosity oil and it may take longer for the higher viscosity oil to
> reach critical
> places in the engine upon startup. High viscosity oil is a poor choice 
> for
> engines that spend a lot of time in warmup. This is not as simple a 
> problem
> as it might seem.
> 
> I used 20W-50 only one time, when I had an oil leak. That slowed the 
> leak
> until I had a chance to fix it. My favorite oil would be 20W-40, but I 
> haven't
> seen that available for decades. I'm now using 15W-40 diesel oil that 
> lacks
> the API seal.
> 
> 
> I've never fogged my engines. In fact, I had to google it to find out 
> what this
> meant. Seems like it's especially popular in the 2-cycle world, but it 
> makes
> some sense. Anyone else out there do it?
> 
> Quiz Question #1, for extra points: What does the W in 20W-50 stand 
> for?
> 
> Quiz Question #2, for extra points: would 30W-30 have constant 
> viscosity?