Interference Engine Or Not?

[Edgar Picazo]

Hi guys,

How accurate is this link from Gates.com explaining this is not an interference engine:

http://www.gates.com/part_locator/index.cfm?location_id=3598

So if my timing belt brakes would it hurt the valves and what not? I don't want to get ripped off by the mechanics since I'm learning as much as possible on these beautiful cars.

Thanks in advance to all of you and happy Easter!

[rickatups]

I have always had the impression that if your timing belt breaks on one of these engines, it is major trouble .... I have never actually heard of a timing belt ever breaking on one of these cars .... kind of interesting. I seem to remember one guy saying he finally changed out his timing belt at 125,000 miles ... honestly I do not think I have the guts to go that long when it comes to my LS 400 .....

These are great cars for sure ..... there are several things to learn about them, but becoming a club member here will put you in a far better position to know all the little secrets ...... I got my LS 400 with 101,000 miles on it .... now it has 138,000 and it still feels great every time I drive it ....

one of my latest discoveries is Royal Purple Synthetic oil ..... that is an interesting subject.....

anyways ..... to stay on topic ..... I think you can go further than 90,000 miles on your timing belt ... but ... how far exactly? Ummmmmm ...... not too sure about that ....

Yes ... Happy Easter !

[billydpowell]

I once bought a 1994 LS400 that ran 206K on the original timing belt.

When it broke, the repair bill was 1800. (in 2002)

I bought it at 230K, put 30K more on it, sold it last Christmas,

still running fine...

BUT, I would not try that...

it looked like this:

[Edgar Picazo]

Thank you all, unfortunately I'm not sure if this is an interference engine or not still.

[OmarG]

i knew a guy who let his 95 timing belt break. his engine was screwed! 95+ IS INTERFERENCE. 90-94 is non-interference. do yourself a favor and use OEM parts only. The japanese made parts are very high quality. trust me on this. Nothin better than OEM toyota (denso) products

[python]

i believe a 95 IS and interference motor

[Von]

I also believe 95' up is interference, but don't know for a fact. I do know for a fact that a doctor in my home town has an SC400 with over 250k with original belt. Before I bought my 93 I almost bought a 98 LS400 with 210k....... with original belt. p.s. I called (2) Lexus dealers and they didn't know !

[Threadcutter]

Hi guys,

How accurate is this link from Gates.com explaining this is not an interference engine:

http://www.gates.com/part_locator/index.cfm?location_id=3598

So if my timing belt brakes would it hurt the valves and what not? I don't want to get ripped off by the mechanics since I'm learning as much as possible on these beautiful cars.

Thanks in advance to all of you and happy Easter!

Edgar;

Gates are incorrect and they have been that way since I can remember. In the second half of '95, Lexus increased the compression ratio slightly and for certain, the 1UZFE's that had the compression increase ARE INTERFERENCE engines. I am not completely certain about the first half of '95 engines, but I strongly believe they are interference as well. Unfortunately, Lexus didn't change the Engine model number to indicate a change from non-interference (maybe) to Interference (Definitely). I've also talked to a couple of Stealers about this and they are selectively dumb as a post.

My strong suggestion is to definitely keep on top of the timing belt maintenance intervals.

[don corleone]

FOR THE LAST AND (HOPEFULLY) FINAL TIME NO PRE 97 ENGINE IS INTERFERENCE! I REPEAT NO PRE 97 ENGINE IS INTERFERENCE. sorry but this is the second most talked about topic on this site. here is some info DIRECT FROM LEXUS that will state the FACT that no engine built before 97 is interference. dont believe your neighbor mechanic or even me for that matter read it for your self. name of the article: "interference verification check for ohc engine.pdf" if you look at the legend you can see that "Manufacturer does not identify engines as having possible interference problems." non interference then look at the engines listed and see if yours falls under the list.

can a Mod change up the stickys. those stickys are just about useless and most are outdated and have little useable info.

interference_verification_check_for_ohc_engine.pdf

[SW03ES]

can a Mod change up the stickys. those stickys are just about useless and most are outdated and have little useable info.

Absolutely. When can we expect you to have a replacement writeup written?

[eatingupblacktop]

Hi guys,

How accurate is this link from Gates.com explaining this is not an interference engine:

http://www.gates.com/part_locator/index.cfm?location_id=3598

So if my timing belt brakes would it hurt the valves and what not? I don't want to get ripped off by the mechanics since I'm learning as much as possible on these beautiful cars.

Thanks in advance to all of you and happy Easter!

Edgar;

Gates are incorrect and they have been that way since I can remember. In the second half of '95, Lexus increased the compression ratio slightly and for certain, the 1UZFE's that had the compression increase ARE INTERFERENCE engines. I am not completely certain about the first half of '95 engines, but I strongly believe they are interference as well. Unfortunately, Lexus didn't change the Engine model number to indicate a change from non-interference (maybe) to Interference (Definitely). I've also talked to a couple of Stealers about this and they are selectively dumb as a post.

My strong suggestion is to definitely keep on top of the timing belt maintenance intervals.

FOR THE LAST AND (HOPEFULLY) FINAL TIME NO PRE 97 ENGINE IS INTERFERENCE! I REPEAT NO PRE 97 ENGINE IS INTERFERENCE. sorry but this is the second most talked about topic on this site. here is some info DIRECT FROM LEXUS that will state the FACT that no engine built before 97 is interference. dont believe your neighbor mechanic or even me for that matter read it for your self. name of the article: "interference verification check for ohc engine.pdf" if you look at the legend you can see that "Manufacturer does not identify engines as having possible interference problems." non interference then look at the engines listed and see if yours falls under the list.

can a Mod change up the stickys. those stickys are just about useless and most are outdated and have little useable info.

Unless you're planning to delve into the Seinfeld Syndrome (Kramer & Newman squeezing out the absolute last mile), WTH difference does it make. Stick with the maintenance schedule and it doesn't matter what your driving! These circular arguments are pointless. It's like arguing who gets wetter crossing the street from one doorway to another in the rain? The one walking or the one running? Use an umbrella! Likewise, maintain your vehicle! That's it, that's all you need to do! If you're running marathons and stretching service intervals, then by all means, show us your bent valves and dented pistons. We all enjoy a a good laugh. :chairshot:

[Edgar Picazo]

Ok got it,

Didn't mean to agitate people in here, yes I'm new at the forum and one of these days I will be wise like you guys. Remember this is my first Lexus and it took me 14 years to achieve my dream of owning one so I want to learn as much as possible on these awesome vehicles.

Best regards. :)

[don corleone]

no problem at all but like eatingupblacktop said this topic goes on and on and on LOL. nothing personal tho.

SW give me sum time and i will search these forums like indiana jones until i compile enuff links and info to have a ALL GEN LS FAQ. sounds simple enuff right?

[PureDrifter]

FOR THE LAST AND (HOPEFULLY) FINAL TIME NO PRE 97 ENGINE IS INTERFERENCE! I REPEAT NO PRE 97 ENGINE IS INTERFERENCE. sorry but this is the second most talked about topic on this site. here is some info DIRECT FROM LEXUS that will state the FACT that no engine built before 97 is interference. dont believe your neighbor mechanic or even me for that matter read it for your self. name of the article: "interference verification check for ohc engine.pdf" if you look at the legend you can see that "Manufacturer does not identify engines as having possible interference problems." non interference then look at the engines listed and see if yours falls under the list.

can a Mod change up the stickys. those stickys are just about useless and most are outdated and have little useable info.

that pdf is wrong.

will bet you $50 that if you go out to a 1uz from a 95MY+ car and pop it open and do some measurements, you will find it is indeed an interference engine.

lexus changed the 1uz heads/pistons/rods for '95 ONLY FOR THE LS400. the changes didnt trickle down to the SC400 for a YEAR.

i REPEAT, 1995-1997 LS400s have INTEREFERENCE 1uz motors.

i'm tired of hearing the same bull*BLEEP* gates argument, many a motor has been lost to their idiocy. unless anyone can show me a genuine TOYOTA/LEXUS spec sheet stating that 95-97 LS' aren't interference, i'll stick by this stand.

that PDF is not from Lexus. Lexus wouldn't refer to a mystical "3rd party" manufacturer, and neither would they try to screw consumers out of a little extra money by making the Timing belt due at 60k miles for the UZ series motors instead of the 90k miles they actually are.

i'm getting tired of the people who find that goddamned Gates info and start throwing up a storm about how they have proof that the 95-97 cars aren't interference. as if it hasnt been seen and lol'd at by half the people on this forum.

[90LS400Lexus]

I have heard so many different answers about the 1995-97 LS than any other car I have ever seen. I know that the 1990-1994 is NOT an interference engine, but like OmarG said, he knew someone with a '95 and if the belt snapped and damaged the engine, then its likely an interference engine. It sure looks like the same engine though.