13
votes
Accepted
Should I use open engine oil that was left over from previous oil change
If the oil is unused, and unopened, there is nothing wrong with using it.
ExxonMobil recommends a five-year maximum shelf life for engine oils,
including Mobil 1™ synthetic motor oil.
Opened ...
- 9,035
13
votes
Accepted
Does Vaseline dissolve rubber?
tl dr - Have no fear of Vaseline and o-rings
O-rings are made out of many different materials. I would suggest that those o-rings which are made to work in the automotive realm are made to be ...
- 153k
11
votes
Accepted
Okay to add new oil to old?
Mixing new with the old will cause you absolutely no issues. As long as you are using the same weight oil, it will mix up and you'd never know it. Continue to change your oil at the specified interval ...
- 153k
11
votes
Should I use open engine oil that was left over from previous oil change
Yes, as Charlie says, as long as it has been stored correctly it should be fine. I generally use the leftovers from one change when I do the next so that it's not sitting around for too long - e.g. if ...
- 28.7k
9
votes
Does Vaseline dissolve rubber?
No.
As far as I can tell, there is no reason that Vaseline might gradually degrade the rubber O-ring on which it has been applied.
O-rings that are manufactured for automotive purposes do tend to ...
- 7,927
8
votes
Accepted
Effects of sunlight on engine oil
Engine oil is normally kept inside a light-proof steel box (your engine), so you might not find much information on how it's affected by sunlight. However, other industries use lubricating oil that ...
- 13.3k
7
votes
Accepted
What type of Brake Lube to use
Two lubes are needed to properly lubricate caliper type brakes.
Silicone is used on the slider pins and anything that touches rubber. A generous amount that completely coats the pin, hole wall and ...
- 11.6k
7
votes
Is WD40 a penetrant?
http://www.jalopyjournal.com/forum/threads/best-penetrating-oil-for-stuck-nuts-bolts.773380/
There was a study done on penetrating oils. Here's the highlights -
The break out torque required for: ...
- 8,443
6
votes
Is WD40 a penetrant?
WD40 is not a penetrant, and as far as lubricants go, it's a poor one. Get a legit penetrating oil at the car parts store. They come in spray cans and range from $7 to $15.
- 12.2k
6
votes
Accepted
Which grease should I use on wiper mechanisms?
Use the lithium or silicone grease!
Copper grease is primarily used to prevent the seizing of parts which become extremely hot, like the exhaust system. But it is not a lubricant in first place. The ...
- 7,047
6
votes
Accepted
What prevents engine oil from mixing with petrol in motor bikes?
The piston rings prevent the two from mixing freely.
Note that it isn't possible to have the two perfectly isolated from each other. There will be a little bit of oil that gets burned during ...
- 39.1k
6
votes
How does ambient temperature affect engine efficiency and fuel consumption?
Lower "cold side" of the Carnot cycle leads to better theoretical efficiency, sure, but have you calculated how much? 10-20 K colder intake with the same 1000 K combustion temperature affect final ...
- 622
5
votes
What prevents engine oil from mixing with petrol in motor bikes?
Oil Scavenging Rings
There are several rings on a piston. Depending on the application and use of the piston it may have up to five ring grooves near the crown. Here are some points of interest.
...
- 33k
5
votes
Should I use open engine oil that was left over from previous oil change
A bit of a late answer here, but I would agree with the answers already posted: Yes, you can definitely use it. That being said, I would not recommend storing engine oil for more than a few years, ...
- 5,245
5
votes
Will greasing clutch parts make it softer
Don't try greasing anything inside the bell housing. Grease will get thrown onto the friction plate and cause you problems.
If the pressure plate is faulty or a previous owner had a heavier plate ...
- 34.6k
5
votes
Accepted
Grease/lubricate rubber stabilizer bar bushings?
In the seldom cases I saw them the manual advised to use soapy water to install them as petroleum based lubes degrade rubber. Normally grease is included on items that need it. Make sure to torque ...
- 8,448
5
votes
Accepted
Assembly lube for engine that has been sitting for years
As you suggested, absotutely use assembly lube on the parts you've taken apart and cleaned. This will ensure there's no wear there while the parts are waiting on oil pressure to build-up and lubricate ...
- 153k
5
votes
can i use api CJ-4/SN in a gasoline car?
Your annual temperature range is -10C to 35C.
The oil viscosity of 15W-40 means that the oil is no thicker than straight SAE 15 oil at winter temperatures and no thinner than SAE 40 weight oil at 100C....
- 5,510
4
votes
Is Anti-Seize a lubricant, abrasive, or both?
Too many either overthink the problem at hand, or have a perverse tendency to distrust "the man," i.e. whoever is determining the current paradigm. Hence, any variety of satisfactory answers are ...
- 41
4
votes
Does Vaseline dissolve rubber?
Yes it might, if it's made from Ethylene Propylene Diene Monomer (EPDM) like what is used on some MAF sensors. It might make your o- ring swell larger so it won't fit correctly anymore.
- 39
4
votes
What is the first point of failure on an engine?
Piston rings are first to wear out most of the time. They are under much mechanical and friction stress, poorly oiled, and subjected to combustion particulates.
Valve stems seals are under no ...
- 11.6k
4
votes
Should I use lubricant or not when installing these spark plugs?
I always use anti-seize whenever I'm installing spark plugs of whatever type for several reasons:
If installing spark plugs into aluminum heads, it helps prevent pulling the threads out with the ...
- 153k
4
votes
Accepted
Is it bad to roll down a hill at highway speed in neutral or with the clutch pedal down in a manual transmission?
If the transmission is in neutral and the clutch engaged, then if the input or primary shaft of the gearbox drives a pump the box will get lubrication, if the box relies on splash lubrication then it ...
- 34.6k
3
votes
Okay to add new oil to old?
Usually when changing the oil you won't be able to fully drain the old oil anyways and the old and new oils will mix, like it or not. Usually this is not a problem even if the weights are different, ...
3
votes
Accepted
Oil low - incorrect oil already in. Stick with the wrong type or add correct type?
It's fine to run Synthetic Oil with crushed Dinosaurs, which is exactly what 'part-synthetic' oils are - but because the chemistry of the two oils you have is unknown, I wouldn't do it for too long (...
- 8,672
3
votes
Do good shocks have any oil below the top half?
A shock absorber is supposed to be dry on the outside, leaking fluid (I suppose you mean that by grease?) is a sign of damage. The more hydraulic fluid a shock absorber looses the worse is it's ...
- 8,448
3
votes
Accepted
Heim joints with zerk fittings
Absolutely. The great thing about having the zerks is when you put fresh grease in, the old grease comes out. With the old grease comes any dirt and grime which may have collected. This should keep ...
- 153k
3
votes
Accepted
Can motorcycle engine be tilted by 90 degrees?
I can only really give you a general answer, since every engine is different. Yes, you're correct in thinking that with a wet sump engine, gravity is what returns the oil to the pan in most scenarios. ...
- 3,012
3
votes
Accepted
Should I use lubricant or not when installing these spark plugs?
It's ok to use the lube if you know what you are doing. Both NGK and BRP are correct, but it's important to understand where the disagreement in these recommendations comes from.
First of all, let's ...
- 146
3
votes
Accepted
What are the dangers of too high TBN?
You might want to read the article here:
TBN Discussion
But the key point on too high a TBN number is:
So should we all use a High TBN oil? There are advantages, but there
are also ...
- 12.1k
Only top scored, non community-wiki answers of a minimum length are eligible