Thermostat failure

Is there any way of preventing a thermostat failing or is it just bad luck. I have a Primera with 39,000 1998 2.0SLX which failed and warped the head. I suspect this may be due to the car spending long periods unused in a garage (previous owner rarely used it) My previous Nissan Bluebird did

172,000 and it was never replaced!!
Reply to
David Wood
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They just die every so often. I suppose changing the coolant occasionally would help in some cases.

Reply to
Doki

Yup, I can't think of anything else to prolong their life off the top of my head. I thought that they were supposed to fail safe though?

Reply to
Malc

Nope, wax thermostats fail closed. (never seen any other type)

Reply to
SimonJ

All the ones I've replaced have been due to them being slightly open when cold preventing proper warm-up. I'ld say that's failed safe. It seems they are always twisted so they don't seat but have a gap round one side. Never yet seen one that's truly failed by leaking it's wax.

Unless a long life coolant is used the coolant should be changed at 2 or 3 years and every 2 thereafter. The stat should be changed at the same time. Judging by the cars I've see on dealers forecourts with nicely stamped up "FSH" this is never done. Brake and clutch fluid also appears to never be changed but again is yearly service item. If the coolant isn't clean and the brake fluid is black you can take it that FSH is a total fabrication.

The quality of the mechanical and electrical parts for the old rwd Bluebirds was and is on par with the very best. I looked at the stat a few times and compared to the stat on my 200SX it could have been made for military service. Even the batteries lasted over 10 years (had 3 so it's not a fluke).

Reply to
Peter Hill

From my reading, a thermostat is considered past its best after 5 years (age, not mileage), and should be changed, irrespective of its state of health, to forestall trouble, which can be so catastrophic, as has been experienced by the OP, if not sported early. The coolant temperature gauge is unfortunately not always dependable, the *only* visual feedback you have of what is happening. If the heater is blowing too hot, one may be alerted of coolant (and engine) overheating, but this telltale symptom is only normally available in winter. It is odd that I have never come across service schedule mandating routine renewal of thermostat. (The same can be levied on a routine renewal of all hoses, regardless of health).

Yes, the radiator is flushed (loose iron and/or aluminium debris) and descaled (attached calcium salt) annually after the third anniversary. The coolant (after careful filtering) can be reused -- I don't; I change that every alternate year -- if desired especially the newer variety which is supposed to hold its anticorrosion (especially of aluminium) property up to 10 years.

Reply to
Lin Chung

Erratum: "spotted" not "sported".

Reply to
Lin Chung

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