Timing Belt

[bigjimpack]

Why does Subaru still use a timing belt. Eventhe newcheapo suzuki sx4
has a chain

 

[Bugalugs]

Why does Subaru still use a timing belt. Eventhe newcheapo suzuki sx4
has a chain

Troll

 

[bigjimpack]

No truth. Timing belts just a ripoff for consumers

 

[Tony Hwang]

No truth. Timing belts just a ripoff for consumers

Hmmm,
It is lighter, costs less.

 

[Carl 1 Lucky Texan]

Hmmm,
It is lighter, costs less.

One moving part vs hundreds!

;^)

Carl

 

[Todd H.]

Why does Subaru still use a timing belt. Eventhe newcheapo suzuki sx4
has a chain

Which also has a service interval.

 

[Clamstrippe Fecadunker]

Why does Subaru still use a timing belt. Eventhe newcheapo suzuki sx4
has a chain

if you want transportation that never requires you to service it
ride the bus (please).

 

[AS]

I am with jim on this one, I think belts are a big business and a lousy
alternative, the owner ends up putting out the money the manufacturer
saved, but:

Chains: Normally last the life of the engine, are noisy, sprockets and
idlers are lubricated by the engine, you hardly ever hear of
catastrophic chain failure.

Belts: Quieter, low cost, idlers have bearings which will require
replacing at least every other belt change, belts are guaranteed to
fail, and sometimes even ahead of time, (think Audi)

Gears: Expensive, wont allow for flexible engine designs.

Hurray for rotary engines with no valves.

 

[Bugalugs]

No truth. Timing belts just a ripoff for consumers

So if you're going to make statements like that, back it up.

How many engines out there are fitted with timing belts, how many with
chains, how many with gears ?

Why is Subaru better/worse than any others?

 

[Dano58]

Why does Subaru still use a timing belt. Eventhe newcheapo suzuki sx4
has a chain

For the same reason that Honda and Toyota still do - cost, quietness
compared to a chain, lightness, etc.

Dan D
'99 Impreza 2.5 RS (son's)
Central NJ USA

 

[Todd H.]

So if you're going to make statements like that, back it up.

How many engines out there are fitted with timing belts, how many with
chains, how many with gears ?

Why is Subaru better/worse than any others?

A more intriguing question is "why are so many engines interference
designs where a belt failure is catastrophic?"

I believe the answer on that has to do with efficiency of the cylinder
design, et al, but it's never been explained to me in sufficient
detail for me to fully get on board with that.

 

[AS]

By the way some of you argue seemingly in favor of timing belts, I guess
you like to shell out money and spend time replacing timing belts. I do
not.

 

[S]

Hi BigJim, All!

Why does Subaru still use a timing belt. Eventhe newcheapo suzuki sx4
has a chain

A belt probably gives a more consistent valve timing over the life of
the belt, and doesn't require an oil bath. Useable at higher RPMs too.

Perhaps a better question would be:

"Why do manufacturers insist on putting interference engines into
consumer vehicles?"

A broken timing belt or chain is merely an inconvenience in an NI
motor, but is often a disaster of the highest degree (read "new
motor") on an interference engine.

And I fully understand that an interference type head/piston
arrangement means higher flow, more power, possibly even slightly
better efficiency, but it _also_ means that you'd better watch that
timing belt, buddy! Or else!

Just as an aside, last summer I acquired for cheap a '99 Forester with
under 100K that had what sounded like a bad rod bearing in it's 2.5L
SOHC motor. Turned out to be a failed idler bearing. (Bonus!)

When I performed the 105K service on my wife's '02 Forry (also with
the SOHC motor) a couple months ago, the belt looked OK, but several
idlers were going, particularly the same cogged idler that had failed
on mine.

What this means is that simply replacing the belt does not guarantee
that you're good to go for another 100K; you absolutely _must_ check
all of the idlers that the belt rides on (including the waterpump),
and replace any that aren't perfect. Or, do as I do, and simply
replace everything while it's apart. $igh.

And just one final note; I have heard it said that the EJ22 (as found
on early Legacys/Imprezas) is an NI engine. Don't count on it; I've
seen at least two with bent valves resulting from timing belt failures
.. . .

ByeBye! S.


Steve Jernigan KG0MB
Laboratory Manager
Microelectronics Research
University of Colorado
(719) 262-3101

 

[houndman]

Hi BigJim, All!



A belt probably gives a more consistent valve timing over the life of
the belt, and doesn't require an oil bath. Useable at higher RPMs too.

Perhaps a better question would be:

"Why do manufacturers insist on putting interference engines into
consumer vehicles?"

A broken timing belt or chain is merely an inconvenience in an NI
motor, but is often a disaster of the highest degree (read "new
motor") on an interference engine.

And I fully understand that an interference type head/piston
arrangement means higher flow, more power, possibly even slightly
better efficiency, but it _also_ means that you'd better watch that
timing belt, buddy! Or else!

Just as an aside, last summer I acquired for cheap a '99 Forester with
under 100K that had what sounded like a bad rod bearing in it's 2.5L
SOHC motor. Turned out to be a failed idler bearing. (Bonus!)

When I performed the 105K service on my wife's '02 Forry (also with
the SOHC motor) a couple months ago, the belt looked OK, but several
idlers were going, particularly the same cogged idler that had failed
on mine.

What this means is that simply replacing the belt does not guarantee
that you're good to go for another 100K; you absolutely _must_ check
all of the idlers that the belt rides on (including the waterpump),
and replace any that aren't perfect. Or, do as I do, and simply
replace everything while it's apart. $igh.

And just one final note; I have heard it said that the EJ22 (as found
on early Legacys/Imprezas) is an NI engine. Don't count on it; I've
seen at least two with bent valves resulting from timing belt failures
. . .

ByeBye! S.

Steve Jernigan KG0MB
Laboratory Manager
Microelectronics Research
University of Colorado
(719) 262-3101

I don't like interference engines, and wonder who they can't cut
reliefs for the valves in the piston tops. I have heard of ones that
had Tripple chains.

I had wondered why I have seen timing belts sold with the idlers. I
should have realized they can go bad, but never owned a car with a
belt. I had a friend who was upset because a mechanic told him his VW
needed a new motor, since the motor had a knock. When the friend told
me his Oil Light was on, and he had been driving it for THREE Mos like
that. I Had to check it out. The knock was coming from the front of
the motor, near the TB cover, and didn't sound like a valve, rod, or
anything I had heard before. I pulled the cover and the idler was
moving with metal shavings on a flange. I told him That was his
knock.

Figured the oil light sending unit was bad or something. Told him to
pick up the parts and I would fix it. Changed the idler and sending
unit, and the oil light was still on. Took it out and poked in the
hole, and the oil light went off, so sludge was blocking it. My friend
was pissed that the mechanic was going to charge him 1600$ for a new
motor. Having a knock and no oil pressure did sound bad, but Not
being able to drive it for very far.

VF

 

[houndman]

A more intriguing question is "why are so many engines interference
designs where a belt failure is catastrophic?"

I believe the answer on that has to do with efficiency of the cylinder
design, et al, but it's never been explained to me in sufficient
detail for me to fully get on board with that.

I thought it was because they are quieter, but wish they were NI.

I read that the SOHC will have less damage if a belt breaks.
Something about the DOHC free wheeling and bending all the valves.

VF

 

[tcassette]

The Subaru H-6 3.0 liter uses a timing chain.

 

[bigjimpack]

How many timing chains in normal applications fail?

 

[Carl 1 Lucky Texan]

How many timing chains in normal applications fail?

One moving part vs hundreds!

;^)

Carl

c'mon buddy - it was a joke!

The flat six 3.0s (like my wife's OBW) have a chain.

I once had a '51 Chevy that stripped a timing gear!


Carl

 

[StephenW]

And if you want to see a mess, take one of those apart.


--
Steve
ASE Master Tech
L1 Diag
Currently residing at a Subaru Shop
4.5 years doing tires and alighnments

 

[Guest]

And if you want to see a mess, take one of those apart.

--
Steve
ASE Master Tech
L1 Diag
Currently residing at a Subaru Shop
4.5 years doing tires and alighnments






- Show quoted text -

Oh, come on, two long-ass chains with tensioners under a cover with
about 300 little bolts, what's not to like?
With the water-pump chain driven, I think.

(03 H6 owner)

Dave