Engine after sitting in humid environment

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Cars been standing for about three months, in very heavy rain (even for summer here) and high temperatures.

I'd expect the high temperatures to maximise the oil drain-off from the valve gear, and the humidity to promote rust, so I had a look before I tried to start it.

Oil is a roughly 1:1 mix of CPC SAE40 and Mobil Delvac MX 15W40 (both mineral, pretty sure the CPC will be Group 1, not sure about the Delvac), and has been in the car for about six years, on low mileage.

Looks OK to the eye, but in some of the photo's the cam's have a reddish tinge. Not sure if this is an artefact, or if the camera is picking up corrosion that my eyes are not seeing.

I dribbled a few capfulls of CPC SAE 40 over the cams and rocker shaft, as a prelim to trying to start it, but then I got interrupted, so that's postponed to tomorrow morning.



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Originally Posted by Silk
Looks like that engine has never run in it's life...I wouldn't risk it.


Lots of people will tell you that with the same non-synthetic oil (half of it "Chinese garbage", sort of) in it for 6 years, its already dead. So nothing to lose.

It used to have some varnish sheets, but I pulled some of it off with an artery clamp when I had the sump off, and most of the rest seems to have dissolved.

How about that reddish tinge? I think its a trick of the lit digits, (picture was taken outdoors with sunlight doing its searing-bolts-of-raw-energy thing) but I'm not sure.

(Not that there's much I can do about it anyway)
 
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Originally Posted by hpb
Daihatsu Charade?


Nope.

Daihatsu Skywing, but mechanically the same, except where it isn't.
 
Originally Posted by SonofJoe
SE Asia: Hot, Wet, Long Long Time...

...sounds like the title of a Chinese Adult movie!


Really?

I'd NEVER, EVER have thought of that.

It MIGHT be considered a circumvention of the local censorship regime, which one should NEVER, EVER do.
 
Originally Posted by Ducked
Originally Posted by SonofJoe
SE Asia: Hot, Wet, Long Long Time...

...sounds like the title of a Chinese Adult movie!


Really?

I'd NEVER, EVER have thought of that.

It MIGHT be considered a circumvention of the local censorship regime, which one should NEVER, EVER do.




As a fellow Brit, I immediately & implicitly understood what your intent was. However the rest of the world does not always share our national prurient interest in things smutty, so my 'pointing out the bleedin' obvious' should be seen as giving a helping hand to the less 'lavatorially aware' folks here on BITOG!
 
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What they don't know don't hurt them.

But isn't "lavatorial" more a German thing?
 
Originally Posted by Ducked
What they don't know don't hurt them.

But isn't "lavatorial" more a German thing?


Maybe the Angles & Saxons bought it over with them when they invaded us all those years ago and it became a cultural fixture.

In the same vein, did you know that in my living memory that there were pockets of The Black Country where people referred to houses as 'Hausen'?
 
Originally Posted by SonofJoe
As a fellow Brit, I immediately & implicitly understood what your intent was. However the rest of the world does not always share our national prurient interest in things smutty, so my 'pointing out the bleedin' obvious' should be seen as giving a helping hand to the less 'lavatorially aware' folks here on BITOG!

May I just point out...the Aussies love all things smutty too, and this Colonial Boy certainly "got it!"
 
Originally Posted by dlundblad
The same oil has been in your engine for 6 years and it looks like that?

I'm impressed.


I was a bit surprised. It was never very mucky but I don't remember it being as shiny as that, though there is that reddish tinge to the cams.....Some of the apparent relative shinyness could be simply because nearly all the oil has drained off, which might also explain the reddish tinge....

Mileage lower than an American would believe possible, though. So low I havn't measured it lately, (as in, for the last couple of years) though I probably could if the mileometer still works.

I did do some very short wasteful OCI's with Delvac MX 15W40 before the current fill, when I had a lot of metal in my oil. Wish I hadn't 'cos I can't get that stuff here any more.

Plus maybe Group 1 solvency, though that's getting a bit techno-speculative.
 
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What‘s that engine called? Looks familiar! I reckon its a Mitsubishi engine, Daihatsu used them a lot in their earlier years.

Anyways, nice, clean engine! But change that oil and check that valve clearance!!
laugh.gif

I don't think we honestly need to stress that 6 years old oil, no matter of what colour, is done. Just put in cheap new oil, anything of similar viscosity will do the trick and anything is better than 6 years old oil. Probably it‘d also run on straight SAE40.
I have one of those old Mitsubishi engines and it is allowed to take SAE 30 if temperatures are over 0 degrees celsius.
So maybe it would work to just use SAE40 in your climate.

Pulling the valvecover and wondering about strange discolourations but not changing the oil.
 
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Originally Posted by Mitsu_Joe
What‘s that engine called, look familiar! I reckon its a Mitsubishi engine, Daihatsu used them a lot in their earlier years.

Anyways, nice, clean engine! But change that oil and check that valve clearance!!
laugh.gif

I don't think we honestly need to stress that 6 years old oil, no matter of what colour, is done. Just put in cheap new oil, anything of similar viscosity will do the trick and anything is better than 6 years old oil.


It used to be called "My engine", Now its apparently called "My nice clean engine", but its still "My engine".

Re "I don't think we honestly need to stress that 6 years old oil, no matter of what colour, is done"

I don't think we do either, since that would be an assertion without any evidence, and I think we should try and avoid them.

I realise that what you're stating is received opinion, and probably well meant, but that doesn't mean I have to believe it.

Of course, I can't prove the oil is OK without doing a full oil analysis, which I'm not going to do, so the precautionary principle would indicate doing an oil change sometime, maybe soonish.

Havn't decided yet, but if I do one it won't mean I think the oil is knackered, it'll just mean that I chickened out.

I'd be interested to see what one of those Lubricheck gizmo's said about it. Shannow was testing one but if he's reported on it I must have missed it.

Re "Pulling the valvecover and wondering about strange discolourations but not changing the oil." my (fairly mild) concern was about possible corrosion of the steel due to drain-down, as I think my post makes quite clear.

I THINK the colouration is a photographic artefact, though I can't be sure.

Even if its real, an oil change NOW, after the fact, isn't very likely to fix it.
 
Originally Posted by Mitsu_Joe

I have one of those old Mitsubishi engines and it is allowed to take SAE 30 if temperatures are over 0 degrees celsius.
So maybe it would work to just use SAE40 in your climate.



As you say, anything would probably do. IIRC SAE 40 is slightly too thick by the book, though it'd probably be fine. The CPC stuff I can easily get though only has a TBN of around 6.7, which again is probably fine, but given my long OCI's now I like to go a bit higher.

I have one 5L jug of Delvac MX 15W-40, so cut 1:1 with the CPC SAE 40 that'll do two oil changes plus top-ups, (over 10 years on current OCI's.)

I've got a changes worth of very old Mobil Special 10W-40, and about 20L of CPC 15W40 CG that MIGHT be usable, so I'm OK for oil for longer than I'm likely to need any.

I quite like the idea of the 40/15W-40 blend, though, and will probably stick with it.
 
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Well, engine oil is commonly stated to have a shelf life of 2-5 years, that's why they print dates on the bottles.
Probably the conventional oil you use is less prone to oxidation (that mainly gets caused by additives) as its basically just pure oil, especially the SAE40 stuff will be very long-term-stable. Especially in the temperatures you have over there.
But as I stated from my personal experience, I wouldn't stretch it that long. I've seen "That oil still looks okay!" followed by internal engine failures quite a few times by now, so I became rather careful ahahah

The new title of the thread is hilarious on a side note...
laugh.gif


On the other hand I wouldn't worry too much about slight corrosion, I'd just start it up and let it idle for some minutes (or pull the plug wires and just let the starter do some revolutions if you're super careful...), then drain out the old contaminated oil and put new one in if there really was corrosion.
The surface rust would probabaly disappear after the first couple of crankshaft revolutions.
I "revived" my car after sitting for almost 3 years, changed the oil and put a new battery in, then started it that's it.

Corrosion is quite unlikely on those parts however (unless you sit for years and years...), high quality iron (of which internals have to be made) helps a lot in preventing rust.
My car still isnt rusted out after 30 german winters whereas some fiats/alfas in the 80s already started rusting at the factory. And thats true for about any part on cars, if you want to design it to hold up, it will.
Specifically talking about camshafts: on older cars like ours the crankshafts are made from cast-iron. The surface is hardened even further artificially using induction hardening. This leaves an extremely hard and almost rust-proof surface of the camshaft. Once this surface is worn down after "long long time"
wink.gif
, the cam will wear out quite fastly, also its more prone to rusting...
 
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Originally Posted by Mitsu_Joe
Well, engine oil is commonly stated to have a shelf life of 2-5 years, that's why they print dates on the bottles.


That's an old one. No one has ever produced any technical support for those stated shelf-lives (some of which are one year, which is about as bare faced as a corporate lie can be) in any discussions on here, but there is plenty of anecdotal and first-principles evidence to the contrary.

Originally Posted by Mitsu_Joe
Probably the conventional oil you use is less prone to oxidation (that mainly gets caused by additives) as its basically just pure oil, especially the SAE40 stuff will be very long-term-stable. Especially in the temperatures you have over there.


That's a new one. I like conventional oil, but I've never heard that it was supposed to be more oxidatively stable than (by implication) synthetic (where that means something), or that oxidation is mostly "caused by additives", or that conventional oil didn't have additives, or that oxidative stability was greater at higher temperatures. I think perhaps that to some extent you are (a) confusing oxidative with shear stability, and (b) just confused.

What I have heard is that, due to its complex makeup, oxidation of conventional oil tends to proceed more continuously and gradually, whereas with synthetic there's none for a long time, then a rather sudden "error catastrophe".

I've seen it claimed that synthetic drains down less, (which would be a reason to use it in this situation), but I've also seen the opposite claim, so I dunno about that.

Originally Posted by Mitsu_Joe


But as I stated from my personal experience, I wouldn't stretch it that long. I've seen "That oil still looks okay!" followed by internal engine failures quite a few times by now, so I became rather careful ahahah



People sometimes post asking for examples of oil-related failures on here, and they mostly come up empty. Perhaps you could detail your experiences next time.

Originally Posted by Mitsu_Joe


The new title of the thread is hilarious on a side note...
laugh.gif




Whaddya mean, NEW title? Someone been messing with my OLD title?

Originally Posted by Mitsu_Joe


On the other hand I wouldn't worry too much about slight corrosion, I'd just start it up and let it idle for some minutes (or pull the plug wires and just let the starter do some revolutions if you're super careful...), then drain out the old contaminated oil and put new one in if there really was corrosion.
The surface rust would probabaly disappear after the first couple of crankshaft revolutions.
I "revived" my car after sitting for almost 3 years, changed the oil and put a new battery in, then started it that's it.

Corrosion is quite unlikely on those parts however (unless you sit for years and years...), high quality iron (of which internals have to be made) helps a lot in preventing rust.
My car still isnt rusted out after 30 german winters whereas some fiats/alfas in the 80s already started rusting at the factory. And thats true for about any part on cars, if you want to design it to hold up, it will.
Specifically talking about camshafts: on older cars like ours the crankshafts are made from cast-iron. The surface is hardened even further artificially using induction hardening. This leaves an extremely hard and almost rust-proof surface of the camshaft. Once this surface is worn down after "long long time"
wink.gif
, the cam will wear out quite fastly, also its more prone to rusting...


Yeh, I had a lot of metal in my oil when I first got the car and wondered if the cams had lost surface hardening, but (short of maybe DIY nitriding, which I'm unlikely to try) there isn't much I can do about that.

It MIGHT be possible to rig something to dribble oil directly on the cams before starting, like I did manually yesterday. Hmm...
 
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