Cool heater in the cold weather

[Chuffmeister]

Access and removal would be extremely difficult (perhaps impossible?) without removing the dizzy, as it is located right in front of the thermostat housing.

Before you remove the dizzy, mark both the block and the dizzy where they meet at the back of the dizzy clamp and make notes (take photos) of the direction of the rotor arm. This will ensure it goes back the same way and won't mess with your timing!!! It takes about ten minutes to get the dizzy out and take the belt off, but will make your job quicker and less frustrating in the long run. You'll also find it easier removing the dizzy clamp when standing on the off-side of the engine bay!

As for the thermostat and the housing; before you remove it, get an old towel ready to soak up the coolant. I simply cleaned up the thermostat seat in the manifold and replaced it with the new one. A new gasket for the housing smeared with a thin coat of Hylomar will do the trick when putting it back together.

All you have to do now is bleed the system…

Edited to say… I'm not sure if I recall removing the lower alternator bolts and pushing the alternator out of the way…

Edited by Chuffmeister on Wednesday 27th November 09:17

[Dr Mike Oxgreen]

Removing the serp belt is easy. Just put a 14 or 15mm* socket onto the tensioner pulley and lever it up or down**. That slackens the belt and you can just slip it off. You probably don't need to take it off completely and risk forgetting its routing.

My only question on bleeding is how you make a watertight seal between your plastic funnel and the mouth of the swirl pot, and how you remove the funnel and flower pot without spilling coolant everywhere?


* Can't remember which, but it's one of those.
** Can't remember whether it's up or down, and I believe it's different if yours has aircon.

[QBee]

As I need to burp the heating system anyway, and am fairly sure my stat is jammed open, having read Chuffmeister's post I will get a "proper man in" (as dear departed Ray Moore used to say early in the morning on the wireless).

It will probably take me two hours plus a shopping trip or three to make a complete horlicks of something he would do properly, with no leaks and no sheared studs/bolts, in 30 minutes.

I know my limitations.

[Chuffmeister]

QBee said:

As I need to burp the heating system anyway, and am fairly sure my stat is jammed open, having read Chuffmeister's post I will get a "proper man in" (as dear departed Ray Moore used to say early in the morning on the wireless).

It will probably take me two hours plus a shopping trip or three to make a complete horlicks of something he would do properly, with no leaks and no sheared studs/bolts, in 30 minutes.

I know my limitations.

You can test the thermostat once you have it out QBee by putting it is a cup of boiled water. If it opens, the you know it was your stat!

Edited to say… I mean, you know your stat works!

Edited by Chuffmeister on Wednesday 27th November 12:32

[SILICONEKID343HP]

Stick some card board in front of the radiator.

[QBee]

If I drive into town (2 miles) and sit in traffic for 5 minutes my fans cut in. No problem getting the engine warm, more a problem of getting the heater warm. But thanks for the thought, Daz. A quick, if not elegant, solution to a car that doesn't warm up.

[Graham]

I've got to fil my totally empty system, engine and rad been out of the car, so I've bitten the bullet and bought a Bergen vacuum filler jobby that connects to the air line, creating a vacuum in hte system first, which also allows you to test for leaks and then fills the system, hopefully without any air in there


I'l let you know how i get on on sat

[Harrytsg]

You absolutely DO NOT have to remove the distributor on a 97 450, I know, I have one and have changed my thermostat twice (for different reasons) and on both occasions it stayed where it was.
I dont doubt it's easier with it out the way, but not necessary, take your time, use a light smear of instant gasket to hold the actual gasket in place.

[BIGMIKE1]

My 95 400 with no PAS didn't need the dizzy, belt or alternator touching, all I had to do was remove the Dizzy cap as I remember but PAS versions may be different

[Chuffmeister]

You're possibly right about the alternator... I seem to remember it being very awkward with the dizzy in though. I can't see the PAS making much of a difference. Horses for courses, an easy fix either way. Try it with the cap off... no joy, take the dizzy out. The biggest pain is burping the system afterwards... Perhaps my dizzy is different???

Edited by Chuffmeister on Wednesday 27th November 19:30

[Chuffmeister]

You're possibly right about the alternator... I seem to remember it being very awkward with the dizzy in though. I can't see the PAS making much of a difference. Horses for courses, an easy fix either way. Try it with the cap off... no joy, take the dizzy out. The biggest pain is burping the system afterwards... Perhaps my dizzy is different???

Edited by Chuffmeister on Wednesday 27th November 19:36

[Bassfiend229hp]

A900ss said:

The fact that my top hose warms up gradually rather than a gush as the thermostat opens suggests to me thermostat or does an air lock also show those characteristics?

Remember that the stat does have a bypass hole in it so the top hose will warm gently before the stat actually opens...

Phil

[A900ss]

Well the old thermostat is out and is defo stuck open so that's good.

The bad is that 'a well known' TVR parts retailer sent me a thermostat that isn't a big bore thermostat so I now need to wait until tomorrow when the correct one should arrive in the post.