Not 7 related - question about oil changes on a car with timing chains

[Dirty Den]

I was looking here here at what they have to say about my tintop (a Micra).

 

The comments include these:

 

"Must have 6-monthly oil changes to avoid timing chain trouble" and "What to Watch Out For - Dirty oil. Must have clean oil. (VITAL to change the oil at least every 6 months expecially if the car does an ultra low mileage.)"

 

Stupid questions time:

 

OK, so regular oil changes on any car are a good idea (and I actually change it more often than every 7k miles) but why are oil changes necessary to avoid timing chain trouble? Is a timing chain more susceptible to a dirty clogged engine? If so, why more susceptible than a car with a normal timing belt?

 

I guess I'm also asking why they have made a point out of highlighting regular oil changes as something to look out for on my car particularly, but don't seem to make a point out of doing so for other cars?

 

Den

 

 

😬 - Self portrait - still unable to remove the smile!

 

Edited by - Dirty Den on 20 Sep 2002 13:02:22

[Joe 90]

Beats me . I am surprised your micra has a timing chain and not a belt. The usual advice is to listen for rattles or check the adjuster. The timing chain on my merc was so worn it jumped two teeth (4 days after the warranty ran out ) and you don't want to know how much that cost.

 

The premium and sythetic oils are very good these days, and will comfortably last longer than the recommended intervals, but how do you know how much longer 🤔 It's all very confusing.

 

99,000 miles so far

[Dirty Den]

Thanks for the reply Oliver. I was just curious as to why they make a point out of saying the cleanliness of the oil could cause timing chain problems.

 

I realise this might be a 'how long is a piece of string?' question, but how often should the chain be checked, and how often should the adjuster be adjusted?

 

Cheers,

 

Den

 

😬 - Self portrait - still unable to remove the smile!

[stevefoster]

Den, it might have an auto cam chain adjuster.

I had a Datsun 180B as a first car many years ago. That had a meaty timing chain and no

oil recs.

To remove the head you had to drive a tool (made of wood) into the opening of the chain under the OHC sprocket to jam it in place. You could then remove the cam sprocket and remove the cam / head without the auto chain tensioner popping out.

If it did pop out you had to strip the entire front of the engine to get at the thing! Just what we did...

 

Cambelts are dry and run out side the oiled part of the engine.

Belts are lighter and quieter but can snapp if not replaced say every 40K miles in your tin top.

 

As long as you change the oil and filter as specified you should not experience problems...

Honest John's site might be worth checking as I remember it having a ref to Nissan Micra camchains..

/Steve

 

My racing pics, 7 DIY, race prep. Updated often here

Hants (North) and Berkshire area club site

here

 

 

Edited by - stevefoster on 20 Sep 2002 20:32:39

[sjwb]

Almost certainly because it has an hydraulic timing chain tensioner. Pumped out with main gallery pressure and prevented from collapsing by a simple ratchet mechanism. The feed hole is minute, usually less than 1 mm dia.

So you see, a little dirt will block it up and away with the rattles we go. Odd about the change frequency, because Hillman Avengers had such a system and they caused no trouble - the rest of the car did though ☹️

 

Steve B

[Dirty Den]

Hi Steve (Foster) -

 

Cheers for the reply. It was the Honest John website that I read those comments on originally. Nice to know that my tintop has such a reputation for reliability. More money for 7 related stuff! 😬

 

Steve B -

 

Thanks for the explanation - so if you don't change the oil regularly, as advised, then the feed hole blocks and the chain eventually loses tension?

 

Den

 

😬 - Self portrait - still unable to remove the smile!

 

Edited by - Dirty Den on 20 Sep 2002 22:25:44