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1G 220,000 Miles Oil Flush

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'90 GS TURBO

Probationary Member
20
1
May 7, 2016
Apex, North_Carolina
I have a 1990 GS-T with 220k miles that had been sitting for a while before I obtained it, should I use oil flush in an attempt to get gunk out or leave it be to avoid causing leaks? Also if yes what flush do you recommend?
 
I have worked at a few dealers and witnessed this multiple times. The oil flush usually causes the car to burn more oil because it just cleaned off your worn out rings.
 
Change the oil a few times back to back is a good way. Drive it to obtain operating temp a few times and change it out. If its dark, repeat. If it STAYS dark the rings could be letting exhaust gas get past them and into the crankcase. I'd just change it a few times. :)
Black91 is right if it has a lot of deposits in it already? Is the oil cap sludgy or rusty? Thats why you would want to do it gradually IMO.
 
At that milage its not recommended as stated above it could displace sludge or other build up and cause leaks or wvwn worse oil obstructions. You could change the oil back to back and see like stated above, you could drop the oil pan if your in doubt just in case and clean it out or if you really want to flush it I use to put a few qts of atf in the crank case and drive it around anf change the oil back to back, use to loosen a bunch of nasty sludge.
 
I third the multiple oil changes instead of a deliberate flush. Throw in some cheaper semi-syn with a new filter. Put 200 miles on it, drain and refill the oil but leave the filter. Another 200-500 miles later drain and refill with proper oil and new filter. I've not had any problems doing it that way before even with higher mileage and pretty poorly maintained cars - both gas and diesel. You'll know how it is going by the amount of oil you get back out; if it is more than you put in, you're pulling some gunk out if there is any noticeable amount there.
 
Ive had cars sit for 5 years. No flush just oil changes. I did not burn of use any oil and drove the car for years after this. Does the car run right now?
 
i would do a VERY MILD seafome with some cheap regular oil. and run it for 50 to 100 miles all in one shot. then drain and go back to normal.

i recommend this due to the lifters in these cars. especially if it sat for a long time.

i do not normally run engine oil additives as 99% of them are garbage but i have found micro-lubes like lucas and z-max actually do provide a little bit of extra protection. they do not market themselves as a 'engine rebuild in a bottle' but as a assistive agent to the oil. they can help keep our original non revised lifters from gumming up.
 
i would do a VERY MILD seafome with some cheap regular oil. and run it for 50 to 100 miles all in one shot. then drain and go back to normal.

i recommend this due to the lifters in these cars. especially if it sat for a long time.

i do not normally run engine oil additives as 99% of them are garbage but i have found micro-lubes like lucas and z-max actually do provide a little bit of extra protection. they do not market themselves as a 'engine rebuild in a bottle' but as a assistive agent to the oil. they can help keep our original non revised lifters from gumming up.

You got balls kid I like that. I wouldn't touch that with a 10 foot pole that I don't own, unless its a 420a. Due to the oiling requirement of the 4g63 I only run 20w50 VR1 nothing else will ever touch my 4g63. Sea foam shouldn't be driven on more like idled in a garage up to op temp.
 
you gotta have some load on the motor or sea foam doesn't do anything.
these motor have no design spec for 20w50 so unless you did a rebuild with tighter than normal tolerances EVERYWHERE, i would not run a race spec 20w50. heck even a 10w30 full synth is on the outside of what a DSM 4g63 was designed to run.

never purposely idle an engine up to temperature, ever. idling to get some warmth is only for the people in the car on freezing days, it does not do the motor a damn bit of good. that does not mean flog the crap out of a cold motor, it just means drive it nicely till warm.
 
you gotta have some load on the motor or sea foam doesn't do anything.
these motor have no design spec for 20w50 so unless you did a rebuild with tighter than normal tolerances EVERYWHERE, i would not run a race spec 20w50. heck even a 10w30 full synth is on the outside of what a DSM 4g63 was designed to run.

never purposely idle an engine up to temperature, ever. idling to get some warmth is only for the people in the car on freezing days, it does not do the motor a damn bit of good. that does not mean flog the crap out of a cold motor, it just means drive it nicely till warm.
Correct me here, but 50 Weight oil is thicker than the oem 30 Weight. So how would thicker oil make sence on Tighter clearances.. Which is unlikely unless a combination of new parts and oversized bearings were used in conjunction with machining to match.

I run 40 weight and that's because i blue printed everything and honed and grounded up my oil galley system.
 
a lot of newer vehicles run marginally tighter tolerances and regularly call for 20w40 or 20w50 in all but 'extreme' conditions. has to do with materials and shape of passages. we have 'converted' some older style motorcycle engines and there is a measurable amount of horsepower freed up when at operating temp. it is not usually worth the cost unless doing a complete rebuild anyway. plus some people will argue that the thickest weight oil you can run is best for the motor. I have a cannondale motor on my bench now, these things have a super crappy pumping system, some of the tiniest oiling tubes i have ever seen on a 'high performance' engine, and recommend 10w40 at all times.

this could easily turn in to a 'theory vs practice' discussion though.

i will say full synthetics tend to flow better at the same weight so usually a step thicker synthetic can be used in place of recommended weight pure dyno goo. also with things like lucas stabilizers and some of the reputable oil detergent/and additives, what was recommended 20 years ago may not be valid with todays fluids.
 
If your questioning the running of VR1 20w50 I ask that you read this whole thing.

http://store.forcedperformance.net/merchant2/graphics/news/Forced Performance Recommendations for Motor Oil.pdf

The reason you need to run VR1 has more to do with the Zinc content than weight of the oil. Forced performance just happens to have a great write up backed up by extensive testing of the 4g63 engine and different weights and different oils. -See recommended oils section at the bottom and why 90% of oils will lead you to more engine wear, worn turbo seals and less protection in case something goes wrong.

After doing more hours worth of research than I care to admit to.. No other oil will touch my engine and I order mitsubishi oil filters only, after reading about spring rate issues in non mitsubishi filters. They are made by WIX so you could alternatively use WIX filters supplied where I live only by Motion Auto. After being a fan of mobil1 for years since they dropped the zinc content I wont run or recommend it any longer.
 
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i went through the same search a while back when mobile 1 went and lowered zinc content. but remember VR1 comes in a multitude of weights and even synth and non-synth options. plus VR1 is almost completely free of detergents, it was designed for motors that get frequent rebuilds.

the filters are also an issue, wix and the mitsu filter are great, but there are a couple other brands i will run. Bosch, K&N, mobil 1, or the purolators. (K&N and mobil filters seem to be made in the same factory, all 4 are of identical design.) the issue with the oil bypass is caused by oil pressure being super high and folding the spring over, so if you run thicker oil, no balance shafts, unported filter housing, you might knock the bypass out of pretty much any oil filter.

the wix uses a 'better' spring design (coil,not leaf) , but it does not use a actual seal between the the sides of the seat. it is just 2 pieces of metal overlapping that keeps clean and dirty oil separate. so you end up in 6 of 1, half dozen of the other, situation either way.
 
Run a non-synthetic diesel oil for a few changes and the high-detergent content of the oil will clean the engine slowly, which is more-ideal than using any of the products like Motor Flush. While using the diesel oil, stock up on bargain-brand oil filters and spin a new filter on about halfway through the typical service interval.

You want to avoid sustained high RPM use when running diesel oil as the high detergent content of the oil will cause the oil to foam. This is why racing oils, which are similar in zinc/phosphorus content to the diesel oils, are a LOW-detergent formula and have a shorter drain interval than your typical engine oil when used on street-driven cars.


To recap....diesel oil for low-RPM street use only to aid in cleaning the engine; racing oil with shorter drain intervals once the engine is as clean as you want it to be. Do not run diesel oil in a racing engine or put racing oil in with the expectation of doing a 5000+ mile drain interval.


Due to the oiling requirement of the 4g63 I only run 20w50 VR1 nothing else will ever touch my 4g63. Sea foam shouldn't be driven on more like idled in a garage up to op temp.

Yes, we've been passing that .pdf around the site for many years now. Using VR1 is fine....using 20W50 is too-heavy for almost any 4G63 unless it's built for it. Oil that thick effects how quickly the top end sees oil at startup, how quickly the turbo drains oil prior to being at full operating temp, and of course oil pressure as well. Maybe FP likes 20W50 best because in Texas where it's 110*f in the summer it holds up better than 10W30....but we started with 20W50 Brad Penn in the race car and oil pressure never dropped below 100psi which isn't good for anything in the oiling system. Dropped to 15W40 and it improved a little, but mainly only when it was at operating temp.

Finally settled on 10W40 for the best all-around performance over the entire year...and that 10W40 has gone 8.56 and 167mph so obviously it's not a matter of oil weight but the additive package the oil contains. I would never go below 10W30 unless specifically-advised by someone who built the engine asking for such a thin oil.
 
Yes, we've been passing that .pdf around the site for many years now. Using VR1 is fine....using 20W50 is too-heavy for almost any 4G63 unless it's built for it. Oil that thick effects how quickly the top end sees oil at startup, how quickly the turbo drains oil prior to being at full operating temp, and of course oil pressure as well. Maybe FP likes 20W50 best because in Texas where it's 110*f in the summer it holds up better than 10W30....but we started with 20W50 Brad Penn in the race car and oil pressure never dropped below 100psi which isn't good for anything in the oiling system. Dropped to 15W40 and it improved a little, but mainly only when it was at operating temp.

Finally settled on 10W40 for the best all-around performance over the entire year...and that 10W40 has gone 8.56 and 167mph so obviously it's not a matter of oil weight but the additive package the oil contains. I would never go below 10W30 unless specifically-advised by someone who built the engine asking for such a thin oil.

Thanks for the info I'm just not sure what camp to be in, high oil pressure means your definitely pumping oil through the crank though.. I run clutch to start delete / no balance shafts and was under the impression that higher oil pressure is more ideal and thicker oil so it wont whip off of the crank.. Mostly I'm more worried about crank walk than anything else. Ill let you know if I run into any issues but so far so good with super heavy oil. I even started running 20w50 in my lancer with a 4b11 and it stopped making weird noises and burning oil. It was burning oil with lighter weight was using 0w30 in it and I couldn't keep oil in it, no smoke or anything and minimal dripps. Im not going to say I for sure wont develop any issues but so far not having any.
 
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0W30 is too thin for anything with a turbocharger. I believe the recommended grade for a 4B11 is 5W30, but I wouldn't choose thinner than 10W30 for that engine either unless it's the middle of winter and the car is driven year-round.

High oil pressure will cause the oil to burn or vaporize when it's injected into a tight tolerance under high load instead of lubricating and doing it's job. You want peak pressure to be around 65-70psi max, ideally. The weight of the oil you choose should depend on the oil pressure you're trying to achieve at startup and full operating temp based on how tight your engine is built. Every engine will vary...no two will be the same.
 
0W30 is too thin for anything with a turbocharger. I believe the recommended grade for a 4B11 is 5W30, but I wouldn't choose thinner than 10W30 for that engine either unless it's the middle of winter and the car is driven year-round.

The Lancer is an 08 base model and mitsubishi recommended 0w20.. It was last changed with 0w30 and then I noticed it didn't have oil on the dipstick (dangerously low) in the middle of North Dakota, one of my trucker friends gave me 5qt of 20w50 from his semi and I put 4qt in and drove to Washington. I planned on changing it as soon as I could but after a couple thousand miles and the wrath of winter here I just let it ride because a I don't want to spend 5$ on that car and b it has never sounded better. I'm not saying anyone else should go heavy on a na Lancer, but I did and never looked back. Gas milage has slightly ticked down but not enough to fret over.
 
Change the oil a few times back to back is a good way. Drive it to obtain operating temp a few times and change it out. If its dark, repeat. If it STAYS dark the rings could be letting exhaust gas get past them and into the crankcase. I'd just change it a few times. :)
Black91 is right if it has a lot of deposits in it already? Is the oil cap sludgy or rusty? Thats why you would want to do it gradually IMO.
I have a 98 gsx just rebuilt the motor 2015 but didn't drive it until 2017 it's been in storage sitting but I believe I have excessive crankcase pressure my oil is black after I just changed it and is starting to leak from the oil pan gasket... Just wondering on what could I do to start attacking this problem..i got a catch can, 6bolt block 98 head 16g(eBay) for now stock boost balance shaft kit... I'll be replacing the op gasket today.. Any help would be appreciated
 
I'll be joining you this week as my pan is leaking too. Do not forget that the two short bolts go under your timing belt. If you put the long bolts under there you will chew into your timing bely and ruin it.
 
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