VVT/timing chains failure prevention

[1sttruck]

"In the Nissan SR20DET, the VVT actuator also fails. Its due to excessive wear, and can happen in low mileage cars too. I try to recommend HDEOs as the extra AW additives should prolong the life of these units. "

Weren't the Japanese concerned about chain wear and were trying to get some additional chain wear tests into the next oil spec ?

 

[friendly_jacek]

quote:

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Originally posted by Leo:
In the Nissan SR20DET, the VVT actuator also fails. Its due to excessive wear, and can happen in low mileage cars too. I try to recommend HDEOs as the extra AW additives should prolong the life of these units.

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This what I hinted when I started the thread.
The corolla failure that recently surfaced happened at 65000 miles, just outside the powertrain warranty. The repair cost was $2000 as there was demage to the engine due to wrong timing. It was a second owner, so there could be some long OCI though.

 

[friendly_jacek]

quote:

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Originally posted by clockworks:
It is the same sound produced by these engines when the oil is changed and the filter is dry when the engine is started. For about 2 seconds, the chain rattles until pressure is built. Perhaps this will shed some light on chain and or VVT actuator failure.

Greg

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It's sad that the "professionals" don't take time to fill the oil filter before screwing in. It's so easy in the 1ZZFE engine.

 

[carock]

Yes,diesels dump more soot into the oil. Very few diesels have overhead cam timing chains. Those that do, have chain wear problems unless they have excellent filtration. Gas engines have plenty of soot, and it is this soot that creates many problems.SAE did a paper comparing valve component wear on an engine specially designed with two oil systems, one with normal filtration, and one that protected the system from soot. The protected system showed no valvetrain wear. Almost all engine wear in a modern car is related to soot.This includes chains, bearings, seals, and rings. Eliminate the soot and engine life is greatly extended.

 

[the_oil_dealer]

tell h im its making toyota noises. they'll know exactly what youre talking about

seriously, just be happy you dont own a 5S-FE

 

[eljefino]

Having replaced only a timing chain on a saturn, leaving the sprockets and guides alone, and retracting the tensioner, I can say, on a saturn 1.9 at least, that the chains do stretch.

Was it a half baked mechanical move? Possibly, possibly not, but it made the car shut up a previously infernal racket.

I would look for good AW additives to protect the chain/sprockets and the proper, thin viscosity for flow for the tiny passages. IOW name brand 5w30 with a touch of SLOB.

 

[clockworks]

[/QUOTE]It's sad that the "professionals" don't take time to fill the oil filter before screwing in. It's so easy in the 1ZZFE engine. [/QB][/QUOTE]

I sincerely doubt any real world wear is going to come from that little bit of chain rattle for a second due to a dry filter. Its when the oil is low and the rattling is constant that any real wear will occur. That said, on my own cars, I prime the filter. On customer's cars, however, Im not spending the time to fill the filter, wait for the media to absorb, fill it again, and continue till the filter is full. Thats just how it goes. Now if a customer asks me too, I'll have no problem doing it. Thats what flat rate is all about.

Greg

 

[Blue_Goose]

Is that the sound I hear when I start my car after letting it sit for let's say 1/2 hour after I run into the store? Sort of like a growl and a rattling..oil level is fine

Why would it sound that way if oil level is fine?

The 1ZZ appears to be a noisy engine anyways...when I am just driving around slowly it is making all sorts of clicking and clacking noises...sort of sounds like a metallic clacking that speeds up with the acceleration of the Matrix...is this the timing chain or a tensioner making this racket?

I'd like to get it fixed(don't recall it being there since new) but don't know what to tell the dealer as far as trying to describe it without them pulling their usual(oh it is a normal sound)

Goose

 

[1sttruck]

"Very few diesels have overhead cam timing chains"

Looking at the manual for my Cummins mine doesn't, it has a gear driven cam with pushrods, so that's why I don't hear about timing chain problems :^)

The Taurus has one though.

 

[Wolf_Tm250]

quote:

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Originally posted by clockworks:
[QB] FYI... it is the 2ZZ engine that was designed by yamaha. I work for toyota and and have only seen 2 of these actuators in the 1ZZs fail. Far more common on these engines is excessive oil consumption due to poor maintenence intervals. The rings, especially the oil control ring sticks in their land.

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AFAIK, given that toyota modified the pistons of the last 1zz ( after 2003 ? ), making more holes in the oil control ring land,
I suspect problem was not a sticking, but a poor oil scraped discharge trough the holes...

Bye