Oil change. Revisited?

[Skrambler]

Tried to find my answer in the past posts, but nothing that I could find directly address my question, so, here goes.

After sitting for about 9 months my 41 Plymouth needs to live once again. Question is, after sitting this much time, should I simply drain the old oil out now,,,OR, should I start the motor and drain the oil after it is warmed up?

Sounds like a silly question, but my first thoughts were since the "gunk" has had plenty of time to settle in the pan, just drain it out BEFORE starting the motor and stirring all that has settled up. The motor is a fresh rebuild, (about five years ago to bare block) and only has had three oil changes, not because of mileage, only about 300 miles) but because of time. I run Mobil 1 in it with no issues What would you do? Thank you.

[michael.warshaw]

i would run it then drain the oil, once it hot so most of it comes out, i dont know i mobil is the right oil for a flathead, as i am under the impression that they take a heavy oil not a light one.

[David Strieb]

I'd put a heat lamp on the pan to warm up the oil, then drain it. Why circulate the used oil through the engine again?

[Reg Evans]

300 miles.

3 oil changes.

Mobil 1.

Drive it.

Ditto !

[Skrambler]

Hum, do I not have to worry about any condensation in the "old" oil? My car is in a new tight garage, but it is not heated. I notice that the hubcaps and bumpers on some change over weather days get damp.

If I WAS to change out the oil, with Mobil 1 would you use 10W30 or 10W40?

I notice that I seem to "burn" a bit more oil useing Mobile1, am I just foolinf myself? or does this kinda make sence?

Thank you!

[captden29]

what a topic. opinions on this are like excuses, everybody has one. we all would do something different based on what has worked well for us in the past. i think everybody would agree that the oil in the car does not go bad under the circumstances you described. as far as gunk in the oil, how much could there be with only 300 miles on the motor. it is still at break in. you really should drive the car more often, at least as much as time allows for you.then change it at perhaps 500 miles and then at 1000 for break in, then don't worry about it until it needs a regular oil change. it is more important to lay the car up with clean oil in it rather than changing out clean oil that has been in it for 9 months. i think we all overdo our oil changes, and other than being costly for no reason, and maybe an evironmental thing, that is not a bad thing. if i were using mobil 1 i would want as much use out of it as i could get. at least use it in something else like a mower if you do change it, or if i were close by i would take it. my mower is old and burns oil, so i only use my oil that i change out of other engines. also, 10w 30 would be my personal choice. i use rotella 30w in my 265 flattie. i change the filter every other oil change. works for me and saves money. the car has great compression and burns very little oil. i change the oil before i winterize it but then use that oil next season until it needs an oil change. dennis

[Edward Roberts]

I second this. We get too caught up in what oil companies (or rather, their marketing reps) sell us. I once owned an Eagle Summit whose Blue Book value had dipped below the cost of an oil change. I ran another 30,000 miles only adding oil when needed... never even changed the filter. I couldn't kill that engine.

I don't say this to encourage anyone to treat these engines that way (I really liked that little Mitsubishi engine), but to point out that (almost all) oil today is so much better than what our engines have been running 50, 60, 70+ years on. The machining and lubricating technology today is going to greatly reduce the amount of garbage in your newly rebuilt engine (mine went through the same thing 67 years ago), so you likely have little to worry about. I want my internals to stay clean but the fact is the P.O. ran it without an air cleaner because he "liked the sound." Condensation is bad, but then, there weren't even many heated stables around half a century ago, let alone heated garages. Engines are much tougher than we give them credit for being... just ask my second child.

[randroid]

Folks,

I was in college when Mobil 1 came out and it was used as the topic of study for an advertising class I was taking, which by no means makes me an authority on it but I learned that it shouldn't be used in an engine with fewer than 10,000 miles on it because the synthetic lubricates so well that the engine will never break-in. Skrambler, that might explain why your engine is smoking.

Pigiron is just about to that many miles on the engine and when I put it back on the road I'll probably go with Mobil 1 because I know that by now it's ready for it.

-Randy

[Flatie46]

I'll agree with Randroid and BigDaddyO, I wouldnt put synthetic in an engine till it's completely broken in. As in a 1000 to 1500 miles. That way everything is seated like the rings and valves and such. If rings don't seat or scuff in the engine will use oil and not run to full potential. The thing about synthetic oil is it's so "slick" it wont let parts scuff in and seat. If it were my engine I'd put a good regular oil in it and run it a 1000 or 1500 miles then switch to moble 1. But that's me:).

[james curl]

I think that I would advise driving more than 3,000 miles with straight weight oil before changing to synthetic. I changed to Mobile 1 at 2500 miles and will use a quart every 300 miles. Engine has more than 10,000 miles on it and still uses a quart per every 300 miles. I have very good compression, you can pull the cap off of the crankcase breather /oil filler tube with the engine hot and running and get no blow by. I am running just a little rich which my be washing the oil from the cylinder walls. You can let off of the gas at 60/70 and coast down to 40 and floor the gas pedal and no smoke comes out of the tail pipes. I drip a few drops after a drive of 50 to 100 miles which I find acceptable for a car this age. A little from both ends of the crankshaft and the rear seal in the transmission. But this is not enough to account for a quart every 300 miles. I am at a loss as where the oil goes, I have spent too much time under the car looking for oil on all of the surfaces under the car only to find it dry and clean. I have learned just to accept that I can not always account for where the oil goes. The tail pipes are not oily.

[JBNeal]

Modern engines have tighter tolerances than the flatheads, so the synthetic oils benefit the modern ones most after initial break-in. Our flatheads originally specified SAE 30 grade, but from what I've read, even the cheaper store brand 10W30 provides better lubrication than SAE 30 from the 40s & 50s. I also read that the store brand oils are packaged at the same facilities as the major oil brands, and the packaging is the same even if the labels are different. Knowing these two things, I've switched from Mobil or Chevron SAE 30 to whatever store is having a sale. I've run the '48 & '49 on the cheaper 10W30 and so far, so good. No blue smoke or oil out of the tail pipe, but I've been told by several mechanic veterans that the older engines would always leak some oil somewhere. I drive these trucks less than 3000 miles a year, and I change the oil every spring when flushing the engine. I rigged up a swab to sample the crankcase for deposits at the drain plug and the dipstick, and I also crack open the valve covers to see what's been going on in there. A small amount of sludge collects in the valve chamber and I clean that out annually.

These flatheads were designed to take some abuse, heck I think that filtration was optional on these engines. IMO if we drive these machines occasionally rather than daily, then we don't have to use cutting edge technology to maintain them. A good engine flush annually, then adequate multi-grade oil + filter, and not over-revving the engine, should make the engine last a long time.

[Skrambler]

Thanks to one and all for chimeing in on my question. Lots of great answers, and plenty to now consider.

If I was to change back to "normal" oil, what weight would you guys recommend for MY situation? Regular straight 30 weight, or 10W30?

Any complications changing back from Mobile1 to regular oil?

Again, I appreciate all your comments.

[randroid]

Skrambler,

I've not heard of any problems mixing straight and synthetic oil. I'd favor a multi-vis oil over a straight grade, but this is another can of worms for break-in. For my air cooled VW engine a 30 wt. non-detergent is recommended for break-in (the first 500 miles) and then to a multi-vis, but I don't feel comfortable using non-detergent so I skip that step and have always used 10-30 for everything without any problems.

There will be many more opinions on this, so hang on to your hat and enjoy the ride.

-Randy

[55 Fargo]

My 218 Canadian L head long block , drips a bit of oil, does not smoke that I have seen or anyone else has mentioned.

This driving season I have gone through a quart at about 800 miles, so not bad.

I currently use Shell Rotella T 15 W 40, plan to change at 2000 miles, and replace with same. I would also not be afraid to use House brand oils, some no doubt are the same as name brand products, and a whole lot better than straight 20 or 30, in 1947..

[Furylee2]

Thanks to one and all for chimeing in on my question. Lots of great answers, and plenty to now consider.

If I was to change back to "normal" oil, what weight would you guys recommend for MY situation? Regular straight 30 weight, or 10W30?

Any complications changing back from Mobile1 to regular oil?

Again, I appreciate all your comments.

I am facing the same thing on my 64 Fury. I have about 300 miles on the overhaul, and plan on taking it to OR in two weeks. I am going to change the oil just before I leave, and will use the same Mobil 10W-40 I have in it now.

It was overhauled in 2002, so I'm not worried about the oil in it now, but the same Mobil 10W-40 today doesn't have enough Zinc for the CAM. So I purchased a few bottles of ZPPD on eBay, to add to the new oil when I change it. I think with the low miles on your engine, you might want to consider the same thing.

[55 Fargo]

One Oil that is still high in ZDDP is Shell Rotella T 15W 40, it has 1250 PPM of zinc in it's content, this is as per Shell Oil technical support.

I have miles on my engine, but am thinking of using say 2 quarts of Mobil1 synthetic oil and 3 quarts of Shell rotella T 15 w40. I am not sure if this thinking or approach is correct, or not.

My engine is fairly clean internally, had the oil pan off recently, and had the valve covers off a while back, very little sludge in either, what was there was cleaned out, my oil stays cleaner longer as a result.........Fred

[49powerwagon]

I know that most new synthetics claim compatability with petroleum based, but I still go with the old rule of never mixing the two. I once pulled apart a John Deere Gen-set engine that had had the two mixed, and the oil set up like jello, so stiff the scattered pieces of rotating mass didn`t sink. Spooky.

[55 Fargo]

I know that most new synthetics claim compatability with petroleum based, but I still go with the old rule of never mixing the two. I once pulled apart a John Deere Gen-set engine that had had the two mixed, and the oil set up like jello, so stiff the scattered pieces of rotating mass didn`t sink. Spooky.

Okay makes sense, what are the synthetic blend oil composed of?

Would they be something different?

I wondering if I could use staright synthetic oil in my flathead, even though she has miles on her.........

[oldmrham]

I'm using good ol valvoline 30 w on my p-15 1947 but my question is during an oil change to I pour a quart in the old bypass filter and 4 in the pan?

[greg g]

just put it in the pan, the filter will fill itself. put in 4 run it to circulate, then put in the rest to fill to the mark.