jim beam wrote:

> y_p_w wrote:
>
>>
>>
>> jim beam wrote:
>>
>>> FanJet wrote:
>>>
>>>> "jim beam" <nospam@example.net> wrote in message
>>>> news:dI-dnV2sket57BvfRVn-sQ@speakeasy.net...
>>>> Belts are certainly good for $dealerships$. Their replacement isn't
>>>> preventive maintenance, it's scheduled maintenance - big difference.
>>>> If Honda used a decent chain, the customer wouldn't need to deal
>>>> with it. The Q45 issue was an anomaly. I'm sure there's the
>>>> occasional Honda spun bearing or some other oddity. Maybe the
>>>> customer ought to replace them every 80K.
>>>
>>>
>>>
>>>
>>> if you drive some piece of v8 detroit iron with less than 40 bhp per
>>> liter, you're not going to notice much difference with a bit of chain
>>> stretch. and cam timing errors in excess of 10 degrees of crankshaft
>>> are not unknown. belts don't stretch so they remain dead-on with
>>> timing right up to replacement day. you want a high performance engine?
>>
>>
>>
>> One forgets that chains put a certain amount of stress on motor oil.
>> If people are lax about their oil change intervals and/or use poor
>> quality oils, chains have been known to crap out. Chains create
>> their own difficulties with OHV engines. Belts don't need any
>> lubrication.
>>
> that's right - the longer travel for overhead cams is a much bigger deal
> for a chain at high revs than for a belt. belts have much less mass.
> chains for block mounted cams where the runs are short are just fine.

A chain driving pushrods is fairly short.

If well maintained, most will probably last the life of a car. If
poorly maintained, chains can stretch, jump, or otherwise crap out.
Some of the early Saturns had problems with the oiling pump cover
and how it distributed oil to their timing chains (TSB 97-T-15A).

<http://autorepair.about.com/library/faqs/bl811h.htm>

Chains are often noisier, and GM tried making them less so by using
nylon coated gear teeth. Eventually the nylon would "shed" and plug
up oil filters.

 

jim beam wrote:

> FanJet wrote:
>
>> "jim beam" <nospam@example.net> wrote in message
>> news:toKdnQNjm5DHURvfRVn-og@speakeasy.net...
>>
>>> FanJet wrote:
>>>
>>>> "jim beam" <nospam@example.net> wrote in message
>>>> news:dI-dnV2sket57BvfRVn-sQ@speakeasy.net...
>>>>
>>>>
>>>>> Elmo P. Shagnasty wrote:
>>>>>
>>>>>
>>>>>> In article <jason-1405051024490001@pm4-broad-50.snlo.dialup.fix.net>,
>>>>>> jason@nospam.com (Jason) wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>>> Ask him what happens if the timing chain breaks. Does the
>>>>>>>> engine trash itself, or not? I think Toyota's are the
>>>>>>>> non-interference type which don't trash themselves. At any
>>>>>>>> rate, that's the important question. It doesn't matter if it's
>>>>>>>> a belt or a chain. There's still chance for breaking, and
>>>>>>>> there's still a requirement to change (although a chain *should*
>>>>>>>> go much farther in theory).
>>>>>>>
>>>>>>>
>>>>>>> Great post. It's my opinion that a broken timing belt would in
>>>>>>> most cases
>>>>>>> do less damage to an engine than a broken chain.
>>>>>>
>>>>>>
>>>>>>
>>>>>> That depends on whether the engine is an interference design or a
>>>>>> non-interference design.
>>>>>>
>>>>>> It's not just the physical belt or chain whipping around in there;
>>>>>> it's the pistons and valves you have to worry about.
>>>>>>
>>>>>> With Honda, the valves go down inside the combustion chamber. If
>>>>>> the timing belt or chain breaks, the valves stay down there when
>>>>>> the piston comes back up to top--and all hell breaks loose when
>>>>>> they meet. That's called "interference".
>>>>>>
>>>>>> If the engine is designed, however, such that the valves don't go
>>>>>> down inside the combustion chamber, but rather stay outside the
>>>>>> combustion chamber, it doesn't matter what happens when the belt
>>>>>> or chain breaks. The engine quits running, but a simple belt/chain
>>>>>> replacement fixes the problem. No trashed engine to worry about.
>>>>>
>>>>>
>>>>> but you don't have the performance to worry about either - as a
>>>>> general rule at any rate. in principle, a higher compression ratio
>>>>> and more aggressive valve timing/higher lift cams both contribute
>>>>> to better performance, but require "interference". so it's a
>>>>> trade-off. other factors such as combustion chamber design,
>>>>> port/valve design, can help produce a high compression
>>>>> non-interference engine, but what's good for non-interference tends
>>>>> to be less good for chamber design, i.e. efficiency, emissions,
>>>>> detonation tendency, etc. did i mention that it's a trade-off?
>>>>>
>>>>>
>>>>>
>>>>>> As far as the earlier comment regarding timing chains stretching,
>>>>>> that happened to my brother's 92 Infiniti Q45. He had to replace
>>>>>> both timing chains, at some unholy cost ($2700 comes to mind). It
>>>>>> wasn't that they broke, but rather that they had stretched far
>>>>>> enough out of spec.
>>>>>
>>>>>
>>>>> belts are good. people whine about cost of preventive maintenance,
>>>>> but that's a function of dealer gouging, not design principle. it
>>>>> doesn't take 4 hours to change a belt on a civic, regardless of
>>>>> what it says on the invoice.
>>>>
>>>>
>>>>
>>>> Belts are certainly good for $dealerships$. Their replacement isn't
>>>> preventive maintenance, it's scheduled maintenance - big difference.
>>>> If Honda used a decent chain, the customer wouldn't need to deal
>>>> with it. The Q45 issue was an anomaly. I'm sure there's the
>>>> occasional Honda spun bearing or some other oddity. Maybe the
>>>> customer ought to replace them every 80K.
>>>
>>>
>>> if you drive some piece of v8 detroit iron with less than 40 bhp per
>>> liter, you're not going to notice much difference with a bit of chain
>>> stretch. and cam timing errors in excess of 10 degrees of crankshaft
>>> are not unknown. belts don't stretch so they remain dead-on with
>>> timing right up to replacement day. you want a high performance engine?
>>
>>
>>
>> Sure. Try the Nissan VQ series (just one example). No belts, very high
>> performance. You repeatedly forget to mention the fact that engines
>> with chain driven cams also feature chain tensioners, preventing the
>> cam timing errors you're worried about.
>
> not so. chains /do/ have tensioners, but by definition, they are on the
> "slack" side of the chain and make absolutely no difference whatsoever
> to timing drift.
>
>> So, chain driven cams + decent normal maintenance = no problems.
>> Belts + decent normal maintenance = big $$ scheduled maintenance. Your
>> choice.
>
> sorry, belts came /from/ v. high performance applications & migrated
> /to/ stock vehicles. this is not to say that chains can't work in high
> performance vehicles, but with the mass of the chain, they're not suited
> for high revs.

Please don't tell the Porsche engineers - they've been racing the flat 6
which first appeared in 1963, when the 911 was first shown, for years.

There are few true givens in racing, e.g., for years there was a saying
"there's no substitute for cubic inches" until Porsche got heavily
involved in racing the 917 with Penske's crew. Their overwhelming
success caused the late Mark Donahue, IIRC, to quip "the only substitute
for cubic inches is cubic money".

;)

 

In article <elmop-2F4998.20313513052005@text.usenetserver.com>,
elmop@nastydesigns.com says...
>
>
>In article <1116013866.885890.35010@z14g2000cwz.googlegroups. com>,
> "yahmed" <ahmedyassir@gmail.com> wrote:
>
>> Instead of timing belt, it has timing chain that automatically adjust
>> itself with time so no replacements are required.
>
>Don't believe that. Timing chains do require replacement as well.

True, but a chain only needs to be replaced when you rebuild the engine.
A chain that lives in a nice clean oil bath will last much longer than a
timing belt.

>Ask him what happens if the timing chain breaks.

Chains break much less frequently than timing belts. They usually give
you some sort of warning in advance, by the noise they make.

>Does the engine trash
>itself, or not? I think Toyota's are the non-interference type which
>don't trash themselves. At any rate, that's the important question. It
>doesn't matter if it's a belt or a chain.

Actually it does matter because belts have a shorter life span than a chain.

>There's still chance for
>breaking, and there's still a requirement to change (although a chain
>*should* go much farther in theory).

Not just theory.
------------
Alex

 

In article <jason-1405051024490001@pm4-broad-50.snlo.dialup.fix.net>,
jason@nospam.com says...

>Great post. It's my opinion that a broken timing belt would in most cases
>do less damage to an engine than a broken chain. However, if you change
>the timing belt or timing chain about every 50,000 to 60,000 miles--it's
>very likely that the owner of the car would never have to worry about the
>consequences of a broken chain or belt.

What manufacturer recommends changing a chain at 60k miles?
-------------
Alex

 

In article <koLhe.1950$Ri4.1221@newsread1.news.pas.earthlink. net>,
y_p_w@hotmail.com says...

>One forgets that chains put a certain amount of stress on motor oil.
>If people are lax about their oil change intervals and/or use poor
>quality oils, chains have been known to crap out. Chains create
>their own difficulties with OHV engines. Belts don't need any
>lubrication.

If you change your oil at proper intervals, a chain will live a long time
with no problem. given a choice, I would take a chain over a belt any
time.
----------------
Alex

 

In article <d6gaue$doj$23@newsmaster.cc.columbia.edu>, Alex Rodriguez
<adr5@columbia.edu> wrote:

> In article <koLhe.1950$Ri4.1221@newsread1.news.pas.earthlink. net>,
> y_p_w@hotmail.com says...
>
> >One forgets that chains put a certain amount of stress on motor oil.
> >If people are lax about their oil change intervals and/or use poor
> >quality oils, chains have been known to crap out. Chains create
> >their own difficulties with OHV engines. Belts don't need any
> >lubrication.
>
> If you change your oil at proper intervals, a chain will live a long time
> with no problem. given a choice, I would take a chain over a belt any
> time.
> ----------------
> Alex

Alex,
Which would cause more damage to an engine if it broke while the driver
was driving 60 miles pers hour--a chain or belt?
Jason

--
NEWSGROUP SUBSCRIBERS MOTTO
We respect those subscribers that ask for advice or provide advice.
We do NOT respect the subscribers that enjoy criticizing people.

 

Jason wrote:
> Alex,
> Which would cause more damage to an engine if it broke while the driver
> was driving 60 miles pers hour--a chain or belt?
> Jason

if both engines are "interference"? theyre both likely screwed regardless.

 

In article <jason-1805051728250001@pm4-broad-38.snlo.dialup.fix.net>,
jason@nospam.com says...
>In article <d6gaue$doj$23@newsmaster.cc.columbia.edu>, Alex Rodriguez
><adr5@columbia.edu> wrote:
>> In article <koLhe.1950$Ri4.1221@newsread1.news.pas.earthlink. net>,
>> y_p_w@hotmail.com says...
>> >One forgets that chains put a certain amount of stress on motor oil.
>> >If people are lax about their oil change intervals and/or use poor
>> >quality oils, chains have been known to crap out. Chains create
>> >their own difficulties with OHV engines. Belts don't need any
>> >lubrication.
>>
>> If you change your oil at proper intervals, a chain will live a long time
>> with no problem. given a choice, I would take a chain over a belt any
>> time.
>> ----------------
>> Alex
>
>Alex,
>Which would cause more damage to an engine if it broke while the driver
>was driving 60 miles pers hour--a chain or belt?

About the same. The main thing to consider is that a chain is less likely
to break.
------------
Alex

 

What is all the fuss about.
Why did Honda go for chains on the $ cyl?
Nissan Altima had and continue to have Timing chains.
The 3.5 L V6 is a very good engine and it has a timing chain.
Forget about Nissan.look at these other brands.
Mercedes Benz, BMW, Jag,Rolls, Bentley, Asthon Martin, also all of the top
Italian manufacturers use chains on their vehicles.
Belts are cheaper to manufacture and makes it simpler to work in overhead
cam engines,
Chains have proven themselves over time they are stronger. that is why they
are used on bicycles, motorcycles and CVT trans missions
Chains are used in the transfer cases of most 4 wheel drive systems.as the
most reliable transmission medium.
"Alex Rodriguez" <adr5@columbia.edu> wrote in message
news:d6gam7$doj$21@newsmaster.cc.columbia.edu...
> In article <elmop-2F4998.20313513052005@text.usenetserver.com>,
> elmop@nastydesigns.com says...
>>
>>
>>In article <1116013866.885890.35010@z14g2000cwz.googlegroups. com>,
>> "yahmed" <ahmedyassir@gmail.com> wrote:
>>
>>> Instead of timing belt, it has timing chain that automatically adjust
>>> itself with time so no replacements are required.
>>
>>Don't believe that. Timing chains do require replacement as well.
>
> True, but a chain only needs to be replaced when you rebuild the engine.
> A chain that lives in a nice clean oil bath will last much longer than a
> timing belt.
>
>>Ask him what happens if the timing chain breaks.
>
> Chains break much less frequently than timing belts. They usually give
> you some sort of warning in advance, by the noise they make.
>
>>Does the engine trash
>>itself, or not? I think Toyota's are the non-interference type which
>>don't trash themselves. At any rate, that's the important question. It
>>doesn't matter if it's a belt or a chain.
>
> Actually it does matter because belts have a shorter life span than a
> chain.
>
>>There's still chance for
>>breaking, and there's still a requirement to change (although a chain
>>*should* go much farther in theory).
>
> Not just theory.
> ------------
> Alex
>