Mobil 1 is leaking. Fred or someone else to the rescue.

[sanioll]

92 240sx SE, KA24DE. ALL STOCK, K&N FILTER.

I've always used Valvoline 10w-30 in summer, and 5w-30 during winter. it used to leak a drop a day during winter months, but in summer while using 10w-30 i never had any leaks.

I always had a small evaporation on the head cover, oil was slowly covering it and making it look dirty. but i washed it every 6-7 months so that cover would look clean.

Recently i switched to lovely mobil 1 full synthetic 10w-30. Its a very good oil, i've researched ****load of stuff online before switching. I'm planning to use it all season.

Now it leaks, after 2 weeks. I popped the hood open other day and head cover was damn dirty. Oil evaporated 2-3 times more and around the bolt on the near end there was lots of oil, and it starts going down near the exhaust manifold. it accumulates on the near end a lot.

ALSO, engine leaks about a 1-2 drops every day. I was changing my rear brake pads today and found a drop of oil in the garage floor after car was pulled out.

Should i switch back to regular petrolium?? I dont want to do that.

Is mobil 1 full synthetic 10w-30 too thin?? should i switch to 10w-40? Does mobil1 make 10W-40??

Engine has 114,000 on it. running strong. only problem i have right now is the exhaust heat shields vibrating, very annoying.

I've got redline mt-90 in the transmission and loving it, and switching to synthetic for the engine assumed would be a good idea.

i just wiped the head cover clean, so pictures will be coming soon. lemme drive it for a day or two.

----------------i'm a college kid, simply want this car to last for another 3 years without any problems.

[w1ngzer0]

to thin? mabie one of your gaskets are leaking?

[2_Liter_Turbo]

Switching to a full synthetic after so many miles isn't the greatest idea. You run the risk of causing premature wear due to the clearence issue with the internal parts of your engine (i.e. bearings etc). Your engine is used to running with standard oil which is a great deal thicker than synthetic. With over 100k in miles the clearence of your engine parts is usually too great to use synthetic. Synthetic is best used when you either have a new car (and you use it from the get go) or you rebuild your engine with the intention to run synthetic. Just trying to help prevent engine failure (seen to many already due to the use of synthetic on a tired motor). However the best synthetic's to use are mobil 1, redline, royal purple, and motul. Hope this helps you out. I'd switch back to your old oil.

p.s. change your gaskets, leaking oil is not so great even if it is slow.

[Spectre]

Mobil 1 is one of the best diagnostic tools for finding leaks; it helped me find a leak in my crankshaft seal. The seal was consequently replaced. It's not causing leaks, it's finding them for you.

[guyaverage]

^ I've read that last sentence 4 times and I still dont know what you mean. If it leaked before, he would have seen oil. Dino oil doesnt leak out and evaporate, it drips to the ground like any other liquid. Why switch to a much more expensive oil to identify (or maybe CAUSE) a leak that wasnt visible enough to cause a problem with the regular oil used in the first place? If it didnt leak enough to identify before, but switching to synthetic made it leak enough, it sounds like you didnt so much as find a small problem, but created a bigger one.

Switching to synthetic late in the game certainly MAY cause leaks, but its NOT a rule. I've heard people say they have leaks after switching to synthetic oil and I dont doubt it, because I have had experience on both sides of the problem. Personally I'm not convinced however that the oil is the cause of the problem, at least in my case. It very well may be, but I'm not convinced.

I switched a Toyota 4Runner at 75,000 miles and 4 years later at 110,000 the outside of the engine is dry as a fart. I have a Mazda Mx3 that has had Mobile 1 since about 15,000 miles ( I used regular for the first year or so) and it hasnt leaked a drop, and its sitting at over 155,000 miles right now. I bought my current 240 at 83,000 about 18 months ago and switched to Mobile 1 at that point, and it just started leaking a few months ago at about 93,000 when it started getting really cold out (though it didnt leak last winter, right after I got it). I changed the front seal, it didnt leak for about a month, now it has started again, in the same spot under the pulley. So the NEW seal is leaking, but the old seals (pan, valve cover, rear main, etc) are still fine. Go figure. Personally I think the pulley journal surface (the smooth aft part of the pulley the front seal slides on) needs to be replaced, or at least machined. Then with a another new seal, I doubt it would leak no matter what oil I use. I'm going to wait until it gets a bit warmer out again to see what happens, since it started when it got cold.

I say switch back to regular and see if it stops. If it does, do 3000 mile changes and you'll be fine. If it doesnt stop, you can pretty much use whatever you feel most comfortable with dripping on the driveway. I would replace whichever seal(s) anyway.

[Spectre]

I'm saying that mobil 1 was so thin compared to the 10w-30 pennzoil the previous owner was using, that it crept throught a clearance the pennzoil couldn't.

[sanioll]

so what needs to be done to stop this leak?? should i switch to higher weight mobil??

Do they have something like 10w40?? will 10w40 damage the engine, what effects will it have on the engine?

[240marcuSX]

you could probably just switch off of synthetic and not leak anymore

[180fan]

Synthetics don't cause leaks. Bad seals do. Check the detergent packages of synthetics and check them against dino oils and you'll see why they've got a cleaning effect and should clean up junk that's in there. Old worn seals will leak, just with synthetics you'll know which ones are worn. For a band-aid, switch back to dino oils, but for a long term fix, get the leaking seals fixed.

[crzycav86]

But what about the bearing clearance issue(what ElNegro said)?

Is switching to synthetic on a high mileage motor bad for it?

[2_Liter_Turbo]

In my experience yes. My mother acually switched to synthetic after 135,000 miles on her SC2 coupe. A month later it threw a rod due to too much play between the rod bearing and the crank. If she stayed with regular oil she wouldn't of had to have an engine swap (although the new motor is newer and faster -it still is a saturn hehe-). Same problem happened to my old Honda Accord. I switched, about a month later the motor died. It had about 226,000 miles on it, but had no problems beforehand.

[guyaverage]

My dad bought an Accord new in 1984, drove it for 15 years and 220,000 miles on whatever cheap dino oil was on sale (I did his oil changes so I know that for fact). He then parked it for about 6 months then gave it to me. A new timing belt, flushed the antifreeze, and switched it to synthetic, and drove it 110+ miles daily until I hit 2 deer at 292,000 miles. No problems at all.

That was using Mobil 1, but it was 15w50. Maybe if I had been using 10w30 it would have been a problem?

As an experiment, I bought a quart of Mobil 1 15w50 and cheapy store brand (Meijer) regular 10w30 and put them in the freezer overnight. Poured them into seperate wax paper cups, I cant honestly say I see any difference in how thick one is over the other, if I was blindfolded I dont think I could tell you which is which. I'm going to switch to 15w50 tomorrow and see what happens. I had Mobil 1 15w50 in the Mx3 all last winter without problem, lets see how the 240 does. Maybe my new/old oil leak will stop.

[PalmerWMD]

so what needs to be done to stop this leak?? should i switch to higher weight mobil??

Do they have something like 10w40?? will 10w40 damage the engine, what effects will it have on the engine?

Absolutely.

I dont usully recommend the thinner mobil weights they are kinda thin for a 30 weight compared to others.

Mobil1 0w-40 or Valvoline SynPower 5w-40 or Syntec ( 5w-40 (made in belgium only) are a better fit with your motor IMO.

Fred..

[180fan]

I had no problems with my old SOHC motor using mobil 1. When I made the switch, it was at ~150k. Never had any problems with my motor running 10w-30. I was usually on top of seal/gasket replacement and did inspections frequently.

The thing about the rod bearing and the crank, yeah synthetic oil doesn't cause that. Worn bearings (probably from oil starvation at the oil feed for the bearings on the crank) probably did.

[2_Liter_Turbo]

I didn't say the synthetic oil caused the gap. I'm saying that over time and abuse the engine was worn but used to normal oil which is thicker (within the same weights of course). When you add synthetic oil (same weight again) it is thinner, so there is more play between the bearing surfaces. Now upping the thickness of the synthetic to match the thickness of the normal oil will be fine, as long as you don't live in an area that is quite cold. 10w40 freezes around 0 degress where as 10w30 at about -25 degress etc etc. The "weights" on oil aren't a judge on how thick they are (except within the same brand family), it's just a designation by SAE on the temperature characteristics and properties of the oil.

[sanioll]

Absolutely.

I dont usully recommend the thinner mobil weights they are kinda thin for a 30 weight compared to others.

Mobil1 0w-40 or Valvoline SynPower 5w-40 or Syntec ( 5w-40 (made in belgium only) are a better fit with your motor IMO.

Fred..

thanks Fred. You're the best person to ask when it comes to oils.

i'm guessing i should run this oil for a month or two then switch to 0w-40 mobil1 with pureone purolator filter.

questions:

1. Can I use 0W-40 all year round? is it okay for summer?

2. reason of me switching to full synthetic was to extend the engines life for at least 3 years. Was this a good idea?

3. i get a very small leak on the rear end of head cover, driver side. Should I tighten it up a bit,. just a bit??

4. If not to tighten it ^, then how easy/hard is it to change the head cover gasket. Price? How much time needed? tools, torque wrench??

thanks

[sanioll]

bump

see pre post, i need some answers plz.

and also, where can i get a 0w-40 mobil1????

i was at walmart, pepboys, autozone, and they didn't have any on the shelves. I didn't ask for it though.
Modified by sanioll at 8:52 PM 3/20/2005

[PalmerWMD]

1) yes all your round is good ( except ifg your turbo then in summer thicker)2)difficul;tm to say most amage is done early on, but the befeits of syn nearly always outweigh the penalties( cost)

Fred..

PS: Sorry didnt respond quickly went to Nissan nationals in AZ, just got back to my hotel room in KY 5 min ago

[sanioll]

1) yes all your round is good ( except ifg your turbo then in summer thicker)2)difficul;tm to say most amage is done early on, but the befeits of syn nearly always outweigh the penalties( cost)

Fred..

PS: Sorry didnt respond quickly went to Nissan nationals in AZ, just got back to my hotel room in KY 5 min ago

is it me? or you're drunk!!

[sanioll]

where can i get a mobil 1 0w-40 people?? WHEREEEEEEEEE??

i'm gonna go and check to see if i can ordera box from advance auto parts.

[KADreams]

I found one Advance Auto Parts here that sells it, and even then I have to call and see when the shipments come in. They sell out of it the second they get it in.

About the valve cover, do not tighten the bolts, you will strip them very easily. Replacing the valve cover gasket is an extremely easy job. You won't need a torque wrench, just follow the proper tightening pattern and don't tighten the hell out of them. You will need a new rubber gasket, and a tube of liquid gasket to reseal it.

I would not recommend using Purolator Pure One filters. They filter so well in fact that they are quite restrictive and result in a lower oil pressure. If you are constantly in the high RPM ranges, K&N makes an excellent filter that maintains good pressure and flow. If you are not the high RPM type, the Mobil 1 filters are an excellent choise.

[PalmerWMD]

where can i get a mobil 1 0w-40 people?? WHEREEEEEEEEE??

i'm gonna go and check to see if i can ordera box from advance auto parts.

Autozone.

Maybe Valvoline Durablend would also be a good choice for you, in 10w-40.

Fred..

PS: Sorry for the typos

[Nismo_Freak]

Now upping the thickness of the synthetic to match the thickness of the normal oil will be fine, as long as you don't live in an area that is quite cold. 10w40 freezes around 0 degress where as 10w30 at about -25 degress etc etc. The "weights" on oil aren't a judge on how thick they are (except within the same brand family), it's just a designation by SAE on the temperature characteristics and properties of the oil.

Not all oil formulations have the same freezing points. There are too many additives (namely pour point depressants) and base variation to quantify a single point for all oils.

Here is a graph with the different pour points of oils.



You can find a correlation of freezing point and pour point as it's the crystallization of the oil molecules that inhibits the movement.

[sanioll]

Thanks everyone for your responses to my noob questions.

I got the gasket already and it will be changed tomorrow. Rented torque wrench from autozone too, just dont know how to use it yet. At the same time I am removing my upper timing chain guide too. It is making that ticking noise in a can.

Oh yeah, thanks Fred, i grabbed 4 quarts of 0w40 from autozone. didnt see it before, now they got it though.

I will take some pics and will be making a little DIY here for people who might need.

well, thanks again everyone.

[Chaotic_Warlord]

I had heard that if you're going to switch over to a full synthetic on a higher mileage engine to do it in stages, like start with3 quarts regular oil and 1 quart synthetic blend, and continue until your at full synthetic blend and start over with the synthetic blend/full synthetic mix. THis way your engine has time to get used to the difference of going from standard oil to full synthetic and doesnt go into shock. I'm just curious about somehting though, I've researched this and still can't figure it out, what's the difference in oils, like is 5w30 thicker than 10w30 and is 10w30 thicker than 10w40. I'm so confused, why can't they put a label on the back of the container showing the difference in thickness'.