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Posted

Hi all,

My car is running fine except for a little valve noise. Should i worry about this or just keep on driving? It has 267,180 miles now.

Thanks, Daffy


Posted

a good question, i have read where people say that valve clatter on this car can end ruining the motor over time,does anyone have a definitive answer to this? thanx in advance

Posted

The noise cannot damage the engine , it only makes for it being noisy and for reduced power and gas milage.

Try changing your oil to a thicker one or just changing it depending on the last change time. I also prefer synthetic as it makes the engien much quieter.

I run 20-50 summer

and 0-30 winter

Posted

The noise cannot damage the engine , it only makes for it being noisy and for reduced power and gas milage.

Try changing your oil to a thicker one or just changing it depending on the last change time. I also prefer synthetic as it makes the engine much quieter.

I run 20-50 summer

and 0-30 winter

OK, first off SK, you have GOT to get the 20/50 weight oil out of that motor, that is nearly the weight of the oil we use in humvees (15-40).

use 5w30, year round, makes life easier, and is much less harsh on your engine, with oil that think, you could very well wear out things prematurely (like your oil pump). Its like honey inside your engine.

a good 5w30.

i could see 20-50 weight if you lived in phoenix, where is 125 in the summer, but come on man, you live in CANADA, where it rarely tops 90. i know, cause im 40 miles south and 200 miles to the east of you. nearly the same latitude. your weather is about the same as it is here, and i can tell you these humvess with 15-40 will not start in the winter...not without masssive amounts of help, and blood sweat and tears.

im not saying you have too, but it is my professional opionon. :D

Posted

Hi all, My car is running fine except for a little valve noise. Should i worry about this or just keep on driving? It has 267,180 miles now.

If your LS400 is a first generation engine ('90-'94) then yes you should worry because the ticking noise likely means that at least one and probably 3-4 of your 32 valves are badly out of adjustment (clearances way too loose, degrading engine power and fuel economy and increasing emissions). A temporary fix is to install new valve adjusting shims to bring the clearances back within specs. However, a lasting solution requires replacement of the damaged valve lifters that hold the shims, which in turn requires camshaft removal (and adds some labor time and cost to the procedure).

mehullica, the lexus dealer tech, previously explained the lifter damage problem this way: "The last intake lifter on the driver's side head, near the firewall is also notorious to go bad due to poor oiling in that area. The lifter that hold the shim becomes damaged over time on the #7 intake side. The steel insert that pushes on the intake valve gets pressed towards the shim. This will cause the lifter to sag lower on the valve increasing clearance."

The '95 on up V8 models don't appear to have this lifter damage problem over time on some valves as evidenced by the fact that the valve clearances on blake's '95 LS400 motor were still all within specs after 250,000 + miles.

Posted

not trying to be impractical about it but like i stated in another thread it's gonna cost me 616 bucks to have the valves adjusted, yeah i could probably do it myself but i'm gonna pay them and have it done, so that when a valve falls into the cylinder and screws the motor i can say hey....why didn't you tell me it was messed up( i told them if it looks bad then let me know so i can put new heads on there, instead of wasting money for a temp fix)

Posted

LS uses shims & buckets and Lexus calls buckets as valve lifters. These so call bucket valve lifters are not the same as the traditional hydraulic valve lifters found in other engines.

Posted

okay guys thanks for shedding some light on the valve issue although it may seem that there is some disagreement about whether or not damage can occur, maybe someone else can weigh in? On a different note i used to run 20-50 in my integra cause i would drive 30-40,000 miles a year going from hollywood to south orange county to inland empire almost daily, i thought that would be good protection,however my integra lost a cylinder at 213,000 and i dont think that shoulda happened as well as the motor had numerous leaks, and i attribute that to mostly being because of my insistence that i use 20-50.

Posted

A bit of valve noise is no cause for concern, and mileage and driveability and emissions will not be affected. As to using 20W-50, well if you use it in most modern cars it will void the warranty. Ford and Honda now specify 5W-20, and anything else will actually harm the engine. The old 20W-50 is for clapped out British sports cars like MGB and such, and not for advanced engines like the LS has.

If you had a Jaguar E-type the problem would be if the valves get quiet, meaning the clearances have closed up, and that's bad for valve life. These engines increase the clearance over time, and a very small amount at that. Don't sweat it.

I use 5W-30, just like it says on the filler cap. Mobil 1 synthetic of course, but 5W-30. Year round, any driving condition this planet throws at the car. That's the point of multi-graded oils - they are designed for year-round service.

Posted

I have 270 000 km on my LS ,aslo i actually use 20-40 not 50 as i looked again .

As well it is Motul synthetic based ester ($100 a an change) well beyond mobil 1 in price and protection. When it is hot its pour rate is beautifully smooth but not thin. Also in Toronto we have traffic which is second to New York and California but with higher volume than either as we have 16 lane highways that are at full stand still from 4-6. I do alot of time in this which is why i use a thicker oil. If my engien was new i would not be using such a thicker oil but it is well beyond new.

Posted

I have 270 000 km on my LS ,aslo i actually use 20-40 not 50 as i looked again .

As well it is Motul synthetic based ester ($100 a an change) well beyond mobil 1 in price and protection. When it is hot its pour rate is beautifully smooth but not thin. Also in Toronto we have traffic which is second to New York and California but with higher volume than either as we have 16 lane highways that are at full stand still from 4-6. I do alot of time in this which is why i use a thicker oil. If my engien was new i would not be using such a thicker oil but it is well beyond new.

Do you burn any oil sk?

:cheers:

Posted

In the late 1970's, before there were government mandated fuel economy standards, Toyota owners manuals recommended 20W-40 and 20W-50 oils for all engines and all temperatures above 10 degrees F http://i5.photobucket.com/albums/y189/mastertech/78.jpg

A good way to find out if it's OK to use 20W-40 and 20W-50 oils in a 1UZ-FE Lexus V8 is to consult the owners manuals of 1UZ-FE Lexus's that were sold overseas in countries like Saudi Arabia. The owners manuals of Toyotas sold in tropical climates in other countries of the world typically permit the use of thicker oils.

The valvetrain of the first generation Lexus V8 is quiet and does not tick unless the clearances on some of the 32 valves are looser than factory specs. Looser than spec clearances cause a decrease in engine power and fuel economy and an increase in valvetrain wear and exhaust emissions which in turn reduces the life expectancy of some pricey emission system components.

Posted

I have 270 000 km on my LS ,aslo i actually use 20-40 not 50 as i looked again .

As well it is Motul synthetic based ester ($100 a an change) well beyond mobil 1 in price and protection. When it is hot its pour rate is beautifully smooth but not thin. Also in Toronto we have traffic which is second to New York and California but with higher volume than either as we have 16 lane highways that are at full stand still from 4-6. I do alot of time in this which is why i use a thicker oil. If my engien was new i would not be using such a thicker oil but it is well beyond new.

Ah,...still 20w40 is thick too...i woudl go for like, 5w30, thats what i use, maybe 10-40 would be the thickest i would ever go, in any gasoline engine.

however, it is your car and it seems to work for you, so more power to you LOL.

Posted
The '95 on up V8 models don't appear to have this lifter damage problem over time on some valves as evidenced by the fact that the valve clearances on blake's '95 LS400 motor were still all within specs after 250,000 + miles.

When we checked the clearances at 270k, there was actually one valve that was a thousandth off (I wrote the wrong thing in that varnish thread. ;) At any rate, the clearances are nearly perfect after 300k, so I can't complain!). To me, it was nothing worth tampering with since my ears couldn't detect any valve clatter noise (we only checked them as a precautionary measure while we were changing the valve cover gaskets.). Not to mention, I couldn't find the shim locally, and I wasn't going to wait a week for something that was pretty inconsequential to me.

Ford and Honda now specify 5W-20, and anything else will actually harm the engine.

Jiffy Lube accidently put 5w30 in my Uncle's Town Car one time, and it consumed enough of the 5w30 to trigger the idiot light. His mechanic was baffled since the bottom side was dry, and my uncle never noticed any clouds or puffs of smoke. A quick look at the recipt revealed everything. After he put the right oil in, it has been running perfectly. You can always count on Jiffy Lube to screw even the simplest things up!

Posted

well i don't even think i'm gonna try to mess with mine at all then, not if they can hold up to that kind of milage, i'm way under that right now, i really thought about trying to freshen the heads up but it just really is impractical

when there are about a million other things that i could throw 1000 dollars at i guess, after reading the service manual too i might check and adjust myself because it's too easy (more like an american vehicle that i expected) and i'd hate to give up 600 to the dealership even if i can't adjust them for some reason they still can't be that far out of adjustment

Posted

well i don't even think i'm gonna try to mess with mine at all then, not if they can hold up to that kind of milage

But Blake has a '95 model which had some updated engine features, including (presumably) improved oiling to the particular valve lifters that tended to suffer wear on the first generation LS400 motor. I know for sure from first hand experience and reading other posts that the '90 & '91 models have this wear problem and it can show up as a ticking noise at warm idle in as little as 70,000 miles. Whether or not the '92-'94 models also have the problem too I can't say for sure. In any case, if your '94 V8 doesn't have any ticking noise at warm idle then none of your valve clearances are likely badly loose. Checking the 32 clearances is actually quite easy once you get the valve covers off. Adjusting the clearances (if needed) is more complicated.

Posted

But Blake has a '95 model which had some updated engine features, including (presumably) improved oiling to the particular valve lifters that tended to suffer wear on the first generation LS400 motor. I know for sure from first hand experience and reading other posts that the '90 & '91 models have this wear problem and it can show up as a ticking noise at warm idle in as little as 70,000 miles.

i was reading the sevice schedule for the car and it actually says that the adjustment is supposed to be done at 60,000, hey blake if you have the info what does your car call for if it is even in the manual?

hey do you think it would be possible in theory to increase oil flow by chaffering or polishing journals, and yeah there is a slight tapping at warm idle especially when first accelerating, it levels out after a bit of driving though


Posted

The valve adjustment check listed in the workshop manuals, and the service schedule calls for an auditory check - they listen to the engine, and if it isn't too loud, they leave it alone. They don't even pull the valve covers.

If it ain't broke, don't fix it. I have a 92 with 150,000 kilometres on it, and it sounds like the day it left the factory. It is every bit as quiet as my 98 GS400.

Be advised that "freshening up" is not needed on these engines. If it has compression, doesn't burn oil, runs normally, leave it alone. Lexus does not supply oversize pistons either - should the cylinder walls be tapered, one replaces the block. Of course, I have yet to hear from anyone who has dismantled the engine for a rebuild, let alone "freshening".

Posted

oh well i guess it just ain't the same as american! i just changed my head on my ford truck last weekend.....haha it had less than fifty pounds because the manifold wasn't tourqued on right and leaked and then you know what that did to valves, so i had to shave the manifold, rebuild the injectors and then slap on a new head and makes great power again with 180 lbs of compression, all for under 500 bucks, crazy to even try to compare the foreign to domestic i guess

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