Timing chain trivia question

You know what works well in an oil bath? A berkeleying chain! I can't believe some people prefer belts

In reply to nicksta43:

Chains are great, till they aren't. Belts have a set expiration date, no guesswork, worry of an old guide grenading, or pulling the covers off to check stretch, just throw a kit at it every so often and you're golden.

The oil bath belt is nothing that new, I think the OHC Honda mower engines have been use that for a while now, and if it will live in a mower for any appreciable amount of time, its gonna be unkillable in a car.

Kenny_McCormic wrote: In reply to nicksta43: Chains are great, till they aren't. Belts have a set expiration date, no guesswork, worry of an old guide grenading, or pulling the covers off to check stretch, just throw a kit at it every so often and you're golden.

Exactly. Like timing belts, old-school V8 timing chains were designed to be wear items that could be replaced without too much difficulty. OHC timing chains typically are not. In many cases, complete engine removal is required to service the chain and/or guides. A belt also has advantages as well in noise, weight and drive losses.

The only reason I can think of that BMW used a chain for the previously posted 3 cyl MINI engine is for space reasons. They squeezed it in on the flywheel side of the engine. In theory, a chain would last about as long as the clutch for most drivers. When the clutch is replaced, service the chain assembly at the same time. Unless you're me - I seem to easily get 200-300K+ miles out of a clutch. I don't know if I'd trust a chain and guides to last that long.

PeefoDaftronic wrote: Honda insight had a 3 cylinder with a timing chain

Was going to say the same thing.

The G10 and G13 Suzuki engines are belt driven. And GM made the timing set in the ECOtec engines easy to change out easily. I just changed it out on the ex's 04 J body. Just have to put a jack under the engine because you have to take out the upper engine mount since the cover gasket is covered by the engine side of the mount and gives you a lot more room to work.

Ian F wrote: I seem to easily get 200-300K+ miles out of a clutch. I don't know if I'd trust a chain and guides to last that long.

I see this mentioned often... what engines with chains often fail before that point? I've only had a few different timing chain motors...

A bunch of Saturns, which will go to that point and well beyond on the OEM chain/guides/tensioner - assuming the rest of the car is still together.

A couple motorcycles where I have never worried about hitting that mileage.

And an S2000, which, aside from the occasional issue with the tensioner (AP1 only?), are pretty rock-solid in the chain department as well.

In reply to ProDarwin:

Pretty much everyone I've personally known with a BMW has had chain tensioner issues past 100K miles.

ProDarwin wrote:

Ian F wrote: I seem to easily get 200-300K+ miles out of a clutch. I don't know if I'd trust a chain and guides to last that long.

I see this mentioned often... what engines with chains often fail before that point?

Besides the VWAG products, Saturns eat chains. It used to be very easy to find Saturns in the junkyard with a big hole in the rear where the chain wadded up and spit out.

I was going to compile a List, but I realized that the list could also be a list of inexpensive cars that have timing chains. So there's probably a strong correlation between "ignored maintenance" and "rapid timing chain death".

This also goes for VWAG with their ridiculously long service intervals.

Honda's t-chains are OK if you ignore the maintenance minder and change the oil more regularly. If you don't, they're good to about 120-140k miles(t-belt interval at 105) and cost 4 times as much to replace.

I like pushrods better.....

Gearheadotaku wrote: I like pushrods better.....

Phhh. Valves...

Honda CB450 was a DOHC twin with a timing chain...

Gearheadotaku wrote: I like pushrods better.....

Pushrods FTMFW!

I dunno about automotive designs but just about every OHC motorcycle out there has a timing chain. That includes my XS650 twin.

Knurled wrote: So there's probably a strong correlation between "ignored maintenance" and "rapid timing chain death".

I've never seen a Saturn spit out a chain, but I don't know that I've been around any that were that neglected. I also never see mention of this on the Saturn forums... you talking about the 1.9, or the Ecotec? I will say, our lemons car chain was starting to make some funny noises, but that happens when your oil is 90% water for several hours of racing.

I would agree on the maintenance. Chains are a lot more sensitive to oil-changes than a belt is. I'd imagine any car prone to oil burning or sludge where the owner skips oil changes would have tensioner problems that could lead to a catastrophic chain failure pretty quickly.

But I wonder if those same owners neglect the timing belt and have similar problems?

ProDarwin wrote: I've never seen a Saturn spit out a chain, but I don't know that I've been around any that were *that* neglected. I also never see mention of this on the Saturn forums... you talking about the 1.9, or the Ecotec?

1.9.

Mind you, we regularly did engine rebuilds at the dealership, often before 90k, for oil consumption. Oil consumption was a huge issue.

So I can easily see someone not checking the oil often enough or just habitually running it a quart or three low all the time, and never changing it because they're adding a quart every couple hundred miles, and either through wear or just loss of oil pressure, the chain guides/tensioner just quit and then it's a short trip from there to the Outside World, Population: Chain.

Outside the dealership level, I almost never see a Saturn come in for any kind of service with anything on the dipstick. What they don't burn, they leak out of the timing cover or head gasket.