mac79

I have a 2001 Sequoia that the timing belt just failed. The belt has 60,000 miles on it and 4 yearsold last replaced by a Toyota dealership.After taking everything apart I also discovered that the water pumpwhich was also replaced with the timing belt is leaking out the weep hole.Also the tensioner was wet from coolant andappears to be stuck and the belt had jammed between the crankshaft positionsensor and the sensor pickup wheel which appeared to cut the belt in half.
I have been reading that this engine is a interferenceengine but I can rotate the crank and the cams without the belt and there is nointerference of any kind, everything feels really smooth and there in nobinding.
Also the engine was at idle when the belt broke and rightbefore the engine turned off the check engine light came on.
I understand Chevy small blocks very well, but this is thefirst time that I am messing with a Toyota engine, ore anything with a timingbelt. I have a theory of what happenedbut am looking for thoughts from those of you that are familiar with the Toyotaengine.

I think that the tensioner was not working properly due tobeing soaked with coolant, the belt came some how jammed and got caught in thecrankshaft sensor cutting it, but also stopping the crank sensor signal turningthe check engine light on and shutting the engine off. Its just a theory.

Is this engine only a interference engine at higherRPMs? Since everything turns freely Iam going to install the new belt and then do a compression test.

What am I missing about the interference fit part?

mikero

I just finished my '04 timing belt/water pump, etc... this morning after the belt stretched so bad it spun around the sprockets an unknown amount of times before quitting. First thing I did was start pricing engines; however, after 8 days of work pulling the cams and going over EVERYTHING I was pleasantly surprised that no non-repairable damage occured. To my understanding the 2UZ-FE is an interference engine. The only speculation I came across was a thread where someone was questioning why 2003, 2004 Sequoia does NOT require setting the crank 50 degrees of TDC. Can't remember where I read it, but I never did figure out why TDC is used when pulling the timing belt in those years. I don't think "why" is all that important- as long as you use TDC in the '03 & '04 and NOT 50 degrees advanced.

mac79

So was there any damage, or just needed to replace the belt?
I had ordered the parts and when I get it all back together I will do a compression test and if there are any bent valves I suspect it will show up in a compression test.

mikero

My compression test & leak down was all within spec range..... I did shut t he truck off as soon as it happened and paid almost $200 to tow it home, but I still figured there would be extensive damage. One of my students timing belt snapped a year or so ago in a KIA (may have been a Hyundi) and every valve was bent. Not one was UN-effected; so, I was assuming the worst and broke down the heads and all valves were within spec (spent 8 straight 12 hour days doing every possible test or procedure). The top end is like new(minus the machining of course)as far as tolerances and being cleaned. Absolutely no damage occurred in the time the belt spun to shut off. Basically all that was needed was to realign the intake & exhaust marks, re -install then reset the timing belt marks with the crank at TDC. All those hours were spent going through every thing according to FSM. It cost me $30 (I had to subscribe to TIS twice) and was well worth every cent. fired up first time Saturday 7AM (I gotta work in the night & early AM cause the desert is already heating up to much in the day here in the Vegas valley) but there was a coolant leak in the inlet. Got that patched last night and drove her for the first time this morning at about 8. Purred like a kitten! I have to return a couple SSTs this afternoon!

mikero

cam*

mikero

MudHippy

cam* what? What does that mean? I hope it means you were trying to correct your previous post about the timing belt stretching. Because that's a load of bulldada.

Who do you teach where? I hope it has nothing to do with anything mechanical in nature.

WTF do those pics prove?

mikero

My apologies OP….
+dirtyhippie –I don’t really know how I failed to recall so quickly -- but thanks for reminding me that -for the most part- these electronic corridors are filled with ego-stroking, dead-end losers who have never accomplished anything or completed anything of any real value in the time they've been given.

I have nothing to prove whatsoever in anything I’ve posted. What I can definitely prove now is that these places are useless. A bit over a week ago I posted my problem at one of these places and not one person gave me any bearing. There was one response; however, it proved to be a just some long-winded egotistical puke that never intended to assist anyone with anything.

Look, even now, when I try to share my experience over the past eight days to offer - if nothing else- a few words to show someone that they are not alone- some 35-year-old loser attempts to hijack the thread in an attempt to appease his own conscious and somehow prove to himself that he is "somebody". Well, guess what? You’re still a nobody who hasn't done anything of any value, or made any lasting contribution to the society in which you were born. All you've done is reinforced a fact I’ve always known anyhow --- oh -- and you've also made sure now that I know the fastest way possible to NOT be member of this-or any other fabricated postulation of reality.
Whom do I teach and where? If I thought you had any manner of intelligence I’d be happy to share— Only-- well… you know where that leaves us…..

mac79

mikero thanks for this information from your experience as it gives me hope that my engine may survive this. My job has taking me out of the country and I brought the Sequoia with me but tools and parts are not readily available so its slow going waiting on tools and parts.


I spend a lot of time on the Corvette forum and it is really good, many responses to any post and never see anything negative. Not sure what's up with this Toyota forum, quite disappointing.

mac79

Just started the Sequoia after replacing the broken timing belt and it seems just fine.

highonpottery

iTrader: (1)

I have no first-hand knowledge of this, but I've read in Land Cruiser posts on iH8mud that the 2uz is designated by Toyota as an interference engine - but the few who've broken their timing belts are reporting no damages, so I dunno. I think I even saw a post from a certified Toyota mechanic who confirmed there's no damage with a tbelt break on 2uz, despite everywhere saying it's interference engine.

Hopefully you got yours all buttoned up and have no more issues in the future. I love the 2uz in my Cruiser, it's a great engine. Just read the other day Toyota traded out a guy who put 1,000,000 miles on his 2uz 2007 Tundra, and gave him a brand new 2016.

mac79

It is a good engine. Mine has 200,000 miles on it and todays compression test showed 190-195 psi.
I was reading that the I think 04 2uz has a bit more power and higher compression. Maybe the newer 2uz has a different piston design and therefore it is the interference fit engine. Just glad mine is working.