Cam chain quality

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Wed 16 Jul 2025 14:41
Cam chain quality - Steveieb

We were always told that cam chains will outlast cam belts but only certain manufacturers chains .

https://m.youtube.com/shorts/NEJ3Z9TY8Y8

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Wed 16 Jul 2025 15:29
Cam chain quality - Xileno

I watch that channel quite a lot, they cover the Ford and PSA wet belts extensively.

I still prefer a dry belt to a chain, provided it's easy to change, unless it's a chain on a make such as Toyota where it's proven.

There is some strong language for those with sensitive ears.

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Wed 16 Jul 2025 16:11
Cam chain quality - Steveieb

A family member had a chain snap on his 74 k miles S4 which ruined the engine.

Placing the chain at the rear of the engine makes it difficult to inspect but the video may explain the quality issue which regular oil changes may not prevent

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Wed 16 Jul 2025 16:14
Cam chain quality - bathtub tom

We were always told that cam chains will outlast cam belts but only certain manufacturers chains .

https://m.youtube.com/shorts/NEJ3Z9TY8Y8

A single opinion proves nothing. I was led to believe Nissan (Renault) chains of twenty years ago were weak. I wondered if an oil sump capacity of 2.7L in a 1500cc engine was more the problem, if it wasn't changed regularly.

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Wed 16 Jul 2025 16:43
Cam chain quality - gordonbennet

Research prior to buying is the answer.

Who the hell thought putting a chain at the rear of an engine was a good idea, barge pole. WTH thought stuffing a cambelt inside the engine running in oil was a good idea, barge pole.

I'm quite happy with cambelts, so long as they prove reliable in service, easy to change and preferably only drive the camshafts.

Mercs always used really good quality duplex chains, trouble very rare indeed, i recall the disgust from my MB indy (yours too StevieB) when he discovered the 1.8 engine in noughties MB C Class was apparently a Mitsubishi sourced engine with a single chain, which reqd replacement around the 80k mark if my memory serves.

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Thu 17 Jul 2025 02:55
Cam chain quality - edlithgow

Gears (as on some Volvo's, IIRC) or a pushrod engine are inherently more reliable and avoid having to decide between the above flawed alternatives.

I've only rebuilt 3 engines. A BMC B series 1800 (pushrod OHV), my Skywing (sub litre 3 cyl rubber band OHC), and a Honda CB clone (125 cc 1 cyl cam chain OHC) but that was enough to rather put me off OHC engines

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Thu 17 Jul 2025 10:09
Cam chain quality - Terry W

Fundamental difference - chains tend to advertise imminent failure through lots of noise, belts just snap.

If belts are not changed as recommended there is usually no visible or audible evidence. On a car 5-10 years old the cost may not be trivial and missed by the then owners.

Does not make chains better or worse than belts - but does explain why belts fail more frequently than chains.

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Thu 17 Jul 2025 11:53
Cam chain quality - John F

Cam chains usually don't drive anything else but the camshafts and tension cogs, but if there is an intermediate shaft (looking at you, Porsche) there can be additional risk of bearing failure. Chains can cause engine failure indirectly because their plastic guides can disintegrate. Cam belts have no guides, but have tension pulleys which press on the back of the belt. The pulley bearing can stiffen, partially seizing and then frying the belt, or causing the crankshaft toothed wheel which drives the belt to wear then strip the belt's teeth before the increasingly stiff bearing actually seizes. Stupidly (or perhaps deliberately for future revenue), some designs make the cam belts also drive the water pump, doubling the risk to belt integrity. But on the whole, good designs with good quality parts hardly ever fail. I have never had an original belt fail in several hundred thousand miles of engine life. (Passats, Focus). Belts can usually be inspected for cracking, crumbling or swelling (Mrs F's Peugeot 2008 has an easily made width tool for this - PSA had a historic problem; apparently supplied with poor quality crumbly belts from DAYCO for its early BIO engines)........

www.honestjohn.co.uk/forum/post/index.htm?t=52783

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Fri 18 Jul 2025 08:09
Cam chain quality - Steveieb

Maybe we had it right with the push rod operated valve system as in the 105 E Ford Anglia which went on to power several Cosworth race engines.

Archimedes comes to mind “ Give me a lever and I will move the world “

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Fri 18 Jul 2025 09:14
Cam chain quality - John F

Maybe we had it right with the push rod operated valve system as in the 105 E Ford Anglia which went on to power several Cosworth race engines.

Or, at the other end of the power spectrum, the cog driven camshafts in the fabulous air cooled boxer 12 of the legendary Porsche 917.....

www.stuttcars.com/porsche-917-technical-details/

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