Do you guys think it will hurt anything to start my stroker 409 with 0w30 oil just long enough to flush the engine out? Maybe long enough to bring it to temp and dump it. It will not be under load, just free rev.
0W30 oil.
- Thread starter Fathead Racing
- Start date
What are you getting some of that for free?
No Ray,it wouldn't hurt a thing if you ran it for a full oil change.All that you'll notice is a slight drop in oil pressure when hot and maybe a hundred rpm increase in idle rpm due to less draw on the oil pump.It's film strength,not viscosity that protects the engine,and 0w-30 has plenty.
Just something I had laying around the shop eft over from a rice burner.
Thanks Don.
You sound like you know something about this. How to determine which viscosity to run in an engine, I often fret over using 15-40, or 20-50 or just plain straight 30w. What do you recommend to decide on the best viscosity?
I'm sure it would be no problem at all.
It used to be a common practice to add gasoline to the engine oil on aircraft that had to sit out overnight during winter in the artic.
I knew a guy that flew up there and he said that the plane's manual would recommend how much gasoline had to be added in order for the engine to start. The colder it was, the more gas you added.
The gasoline would evaporate after the engine ran a while, so the manual also suggested how long you had to run the engine before you could take off.
It sounds weird but I gather it was common practice back in the day. I'm guessing multi grade and synthetic oil, along with more powerful starter motors have made this a thing of the past.
https://www.backcountrypilot.org/forum/oil-dilution-13805
It used to be a common practice to add gasoline to the engine oil on aircraft that had to sit out overnight during winter in the artic.
I knew a guy that flew up there and he said that the plane's manual would recommend how much gasoline had to be added in order for the engine to start. The colder it was, the more gas you added.
The gasoline would evaporate after the engine ran a while, so the manual also suggested how long you had to run the engine before you could take off.
It sounds weird but I gather it was common practice back in the day. I'm guessing multi grade and synthetic oil, along with more powerful starter motors have made this a thing of the past.
https://www.backcountrypilot.org/forum/oil-dilution-13805
The main reason I like synthetic oils is that it dosent drain off the engine parts like the old "dino" oils do.In my bracket engines.like a lot of our old "hobby" cars,the engine spends most of it's time sitting.On a bracket car,unless I needed to drive it to the station for some after hours tweeks,or improvements,it would sit from Sunday night until Saturday morning when Id crank it up,drive it to work,from work to the track,run the crap out of it..drive it home,repeat the drill on Sunday,sometimes at a differant track further away,home again Sunday night.I would typically get 5 years,1500 runs,and 50,000 miles before freashing up the rings.I never had any bearing or cam/lifter issues.Oils have gotten a lot better with their formulations [until the EPA 
made the remove the zinc] since we were kids.In those days a typical auto engine ran a temprature of 180 degrees.Todays engines don't even turn the cooling fans on until about 210,the engine clearances are a lot tighter,and most engine manufacturers recommend oils in the 0w-20 range.even though modern engines rev higher.The modern oil formulations meet standards that were unthinkable even 15-20 years back/There's no reason to think that one of our beloved,half century old engines,when built with modern machining specs,tolerances,and materials need any more than the more modern engines do.If you're going to stick with a flat tappet cam and lifters in order to save money,then you'll have to spend extra money on specialized oils such as Brad penn,or Joe Gibbs,or special zinc additives that cost upwards of 10.00 per bottle for reach oil change to keep the engine alive.Most of the specialty oils are of the 10w-30 semi synthetic varity.I just do not see the need to ever run anything heavier .unless it's a dedicated,race only engine.Look at what the Nascar Sprint Cup engines are doing,oils in the 5w-30 range,9500 rpm,900 hp plus[last year] and will live usually 1,000 or more racing miles.
made the remove the zinc] since we were kids.In those days a typical auto engine ran a temprature of 180 degrees.Todays engines don't even turn the cooling fans on until about 210,the engine clearances are a lot tighter,and most engine manufacturers recommend oils in the 0w-20 range.even though modern engines rev higher.The modern oil formulations meet standards that were unthinkable even 15-20 years back/There's no reason to think that one of our beloved,half century old engines,when built with modern machining specs,tolerances,and materials need any more than the more modern engines do.If you're going to stick with a flat tappet cam and lifters in order to save money,then you'll have to spend extra money on specialized oils such as Brad penn,or Joe Gibbs,or special zinc additives that cost upwards of 10.00 per bottle for reach oil change to keep the engine alive.Most of the specialty oils are of the 10w-30 semi synthetic varity.I just do not see the need to ever run anything heavier .unless it's a dedicated,race only engine.Look at what the Nascar Sprint Cup engines are doing,oils in the 5w-30 range,9500 rpm,900 hp plus[last year] and will live usually 1,000 or more racing miles.
The main reason I like synthetic oils is that it dosent drain off the engine parts like the old "dino" oils do.In my bracket engines.like a lot of our old "hobby" cars,the engine spends most of it's time sitting.On a bracket car,unless I needed to drive it to the station for some after hours tweeks,or improvements,it would sit from Sunday night until Saturday morning when Id crank it up,drive it to work,from work to the track,run the crap out of it..drive it home,repeat the drill on Sunday,sometimes at a differant track further away,home again Sunday night.I would typically get 5 years,1500 runs,and 50,000 miles before freashing up the rings.I never had any bearing or cam/lifter issues.Oils have gotten a lot better with their formulations [until the EPA
So my 50 year old engine is still running 50 year old clearances and runs at 180, temps outside 50 f to 95 f, it is 50 years old and never been apart. What should the determining factors be for choosing viscosity? Outside temp? I use Brad Penn for zinc, I did use straight 30w considering that's what was always used and it's lived well for 50 years. I'm not sure of the exact mileage but I think it's 60-80K
Don't know if the old school thoughts hold any water with the synthetic oils, which I myself run, but old school was for every 1000 rpm you need 10 psi oil pressure. If your old engine makes 50 psi @ 5000 rpm and at least 10 psi @ idle with the oil your using I think you would be ok.
If it ain't broke,don't fix it Mike.
What would be your determining factors for picking a viscosity? On other "old" cars when I use 15/40 I don't like the drop in pressure when it's warmer out, but to get a higher "lower" number you have to go to 20/50, then I think the 50 is too high. I would like a 20/40 but they don't make that. On the original Vet I figured just to do the straight 30w. I'm talking hot rods here not new cars. My new cars get whatever the OEM recommends.
How much of a drop are you seeing Mike? The straight 30 wt,if you can find it is fine for what you're doing. These older engines are going to have some wear on the crank and bearings,but with modern oil formulations and just cruising around,nothing will be hurt in a Chevrolet engine with 45 psi at an occasional 5000 rpm full throttle blast.Big block Fords and some Mopars and Buicks are another matter. I don't get at all concerned with 15-20 psi with no load,other than being in drive,at an idle.If the engines lifters are quiet at that pressure,all is fine,otherwise go up a grade .
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On my 54 truck with a stock type 350 I used 15/40 and it was fine early in the day, say outside temps at 60-65, idle at 20psi go up to 50 at speed but as the day warmed, say 80-85 deg the idle pressure would go down to 10psi, no noise but I didn't like that, of course engine warmed up to 190. I wanted to change to heavier but didn't feel 20/50 was good. I had decided to go to straight 30 in that one but I sold it before oil change was due. In the old days, 30 wt was what was available and no problems. Today all these different weights messes with me.
I just put the straight 30w Brad Penn in the Vet and that's what I'm going to use, screw all this
I just put the straight 30w Brad Penn in the Vet and that's what I'm going to use, screw all this
I used to run full synthetic 5w50 in my 427. It seemed to keep my pressure from being too high on cold starts, but still gave me good pressure after the engine was at operating temps. That engine was a little on the "loose" side though.
61 Bubble
Well Known Member
OK we have and do us 0 weight oils in high RPM stuff. I will ask you guys this:
How would you feel turning 9000 RPM+ in the lights with ZERO oil pressure???
We ONLY will run 0W oils in engines that were specifically designed with this in mind. Tolerances and ring packages change, parts selection changes as well. I would not recommend or us 0W oil inmy own stuff WITHOUT building the engines for it, there are better oils out there for this. I would go with say a 5W40, 10W30 or even 20W50 GOOD quality oil in these older motors. IF the motor has been rebuilt, after say 1000 miles, I would flush and run FULL SYNTHETIC oils. We have had good results with Klotz. Royal Purple did rust some of our internal components.
Now to the OP Fathead. I WOULD NOT under any circumstance fire a FRESH build on 0w oil. IF you concerned, I would use the proper break-in oil of the manufacturer that you intend to use on a regular basis. If that gets to pricey (yet how much could a "scuffed" bearing cost now) then just PRIME the engine very good in a warm location, maybe put a space heater up to the oil pan for a couple hours and prime with conventional 5w or 10w 30's. The warm oil will thin out and get into the places you want yet will still provide protection against "scuffing" and other start up damages. I personally used to us the cheapest 10W30 oil you could find! Like $1.99/quart stuff just for this occasion. Basically to "run-in" the cam/lifters (if needed) and flush the oil passages. Once that was done to our liking, I would dump the CHEAP oil and replace with a good quality DINO oil. Run that till we felt it was enough to seat rings, THEN to full synthetic oils. Sometimes the full synth oils are so slippery that ring seal just doesn't EVER happen.
On my motor that I posted in the "HEAD THREADS" the 498 Pontiac Headed BBc, we had to make 5 dyno pulls to seat the rings. We had as much as 65% blow-by on start up! The valve cover breather was pushing pressure like a old stream locomotive. FULL Synth WOULD NOT SEAT THE RINGS ON A 500" PRO STOCK MOTOR WITHOUT A BANG/LOAD EVER!!!
Hope this helps and these are my experiences.
How would you feel turning 9000 RPM+ in the lights with ZERO oil pressure???
We ONLY will run 0W oils in engines that were specifically designed with this in mind. Tolerances and ring packages change, parts selection changes as well. I would not recommend or us 0W oil inmy own stuff WITHOUT building the engines for it, there are better oils out there for this. I would go with say a 5W40, 10W30 or even 20W50 GOOD quality oil in these older motors. IF the motor has been rebuilt, after say 1000 miles, I would flush and run FULL SYNTHETIC oils. We have had good results with Klotz. Royal Purple did rust some of our internal components.
Now to the OP Fathead. I WOULD NOT under any circumstance fire a FRESH build on 0w oil. IF you concerned, I would use the proper break-in oil of the manufacturer that you intend to use on a regular basis. If that gets to pricey (yet how much could a "scuffed" bearing cost now) then just PRIME the engine very good in a warm location, maybe put a space heater up to the oil pan for a couple hours and prime with conventional 5w or 10w 30's. The warm oil will thin out and get into the places you want yet will still provide protection against "scuffing" and other start up damages. I personally used to us the cheapest 10W30 oil you could find! Like $1.99/quart stuff just for this occasion. Basically to "run-in" the cam/lifters (if needed) and flush the oil passages. Once that was done to our liking, I would dump the CHEAP oil and replace with a good quality DINO oil. Run that till we felt it was enough to seat rings, THEN to full synthetic oils. Sometimes the full synth oils are so slippery that ring seal just doesn't EVER happen.
On my motor that I posted in the "HEAD THREADS" the 498 Pontiac Headed BBc, we had to make 5 dyno pulls to seat the rings. We had as much as 65% blow-by on start up! The valve cover breather was pushing pressure like a old stream locomotive. FULL Synth WOULD NOT SEAT THE RINGS ON A 500" PRO STOCK MOTOR WITHOUT A BANG/LOAD EVER!!!
Hope this helps and these are my experiences.
That's good info. In my case this engine is already run in. I lost a composite distributor gear and have been flushing the engine. I just had this oil in the shop so I dumped it in. I pre oiled and started the engine. At idle with the 0w30 it had 62 psi oil pressure. I was using 20w50 full synthetic when the distributor gear broke. I have taken the suggestions of many on this site and will run 10w30 full synthetic this year and see how it goes. I have a bronze gear now. I probably will buy the newest thing, that would be the Crane gear that says it's compatible with my cam dist. Drive gear.