dtLS400

iTrader: (1)

Hello CL,
New member here, the posts have been my number one source for reading material. I own a 1992 Ls400. The odo just rolled over 230,015 miles. It's been in the family since it was bought from Stevens creek Lexus. I have put about 9 thousand miles on it myself. The car runs great. I had sown major work done including a valve job , ps pump, high pressure hose and rack and pinion. The car overheated because there was a crack in the overflow reservoir but once I put some coolant and replaced the reservoir the car ran fine, I intend to keep this car forever. What other things should check on to keep this car running after it overheated?...
Thanks CL

deanshark

Welcome to CL. It depends on how bad it overheated, like if it was driven while hot and for how long. It could be no problems or as bad as a blown head gasket. (very unlikely) I've only heard of a couple head gaskets going bad. The best thing you can do is search the forum for other threads on overheating and you'll get all the info you need on what to look for and what to do.

emarknot

thermostat.

it seems from what you stated, that it overheated awhile ago, and you've been driving for some time already.

if everything seems to be ok, I wouldnt worry too much about it.

its not like you said..."dude, I was driving and the temp needle was pegged in the red, but I was like 5 miles from my house, so I just kept going.....but it died 4 blocks away from my driveway"

deanshark

Don't you hate it when that happens? Come on now, you've done that, didn't you? Hate to laugh but I've done it. I think most of did something like that when we were young, at least once.
But yeah, you can start by changing the T-stat and maybe a coolant flush. They're both cheap enough and probably necessary.

emarknot

I did once. a very long time ago.

but we get lots of customers...that well....."i just kept driving, it made a funny noise then died"

dtLS400

iTrader: (1)

Thanks everyone for the replies, the overheating was the first major problem,. I first got the car and had been driving it until there was no more coolant in it. It escaped jeough a small crack in the reservoir, notices on the freeway when he needle was pegged in the red. Pulled it over and let cool for a few hours. I had to slowly put it home kn the back roads to get it home, thermostat was fine. Added coolant the next day it ran fine. Next problem was the wrong fluid in the ps system. I put power steering fluid by prestone, it ran ok until I noticed the the steering getting stiff after a few trips.then the whining followed. The ps system was leaking and I would have to bleed the steering with new ATF dexron2. It had to be filled every few starts and stops of the engine, I had it all replaced including the vacuum switch, while all that being done I also had a valve job and replaced a cracked egr pipe. Whew, although it's not as quiet as before it still runs like a champ though.

emarknot

what do you mean.. "not as quiet as before"



now see, I almost called it..... yikes.




whats not quiet. stick with the WHOLE STORY to start, then you may not get a bunch of conflicting opinions......

that youre probably going to start getting.

dtLS400

iTrader: (1)

After I had a valve job done there was a noticeable ticking comin from the engine. It wasnt there even after I took he valve cover off and put t back on. The ticking only came after the valve job .

emarknot

oh that...gotcha....does it still sound kinda sound like a valve tick....or maybe if was low on oil? cause I think I know what that is.......but I need to check something before I say it.

cause if it wasnt there before and it is there after the valve job......theres really only one thing left.......

I be back...

emarknot

gear driven cam preload.


if its what im thinking, this is the problem. it was probably just put together not realizing that the primary cam needs to be preloaded.

just as the toyota 3sfe, 5sfe, and 3sgte motors. I believe the 4age is this way to.

dtLS400

iTrader: (1)

Sounds good thanks for all the input, Im definitely ping to look into preloading the primary cam

willhickey

iTrader: (1)

ima thinking someone didnt shim /check and adjust your valve which is a pita

dtLS400

iTrader: (1)

To: Emarknot, thanks for your input, do you have any words of advice on what to tell my mechanic On what to do?

dtLS400

iTrader: (1)

He said he marked them from where they came off and put it back on the same way,

emarknot

cam preload isnt a markable issue. its a separate gear, on the cam, that drives a chain to the secondary cam.

and by that I mean, we have a 4 cam motor..but its not a true 4 cam motor.

its a master cam, that drives the secondary cam, by a "gear" on the primary cam. the primary cam is the only one with a gear, if you were to do a timing belt, you would have only 2 cam pulleys to contend with. so why 2 cam pulleys on a 4 cam motor?

because again...just trying to sink it in.......the cam that has a t-belt pulley, is the primary cam...there is a chain that runs the secondary cam.....secondary meaning a cam with no t-belt pulley...............and if the primary cam gear isnt preloded properly,the secondary cam is out of wack...thus being your tick.

in.general, its all out of wack, but the preload gear keeps it all together.
as lomg as the secondary cam is in place, ONLY the primary cam needs to be removed,preload the gear,re-installed......all should be good.


it will be monday before I can get any specs

sorry to sound confusing