Hidden-waxstat cold start

[Dollywobbler]

The TZD appears to have an electronic replacement for the wax stat, which I presume is something that came in later in the production run. However, I'm not sure it works because a cold idle is below 1000rpm - I have to manually raise the revs to just over 1000 for it to rise up promptly. I'm guessing there's a duff sensor somewhere, so I guess the question is where and how do you test it?

[citronut]

ooo er missus,
can you add some picy evidence of this peculiarity

regards malcolm

[Dollywobbler]

Here you go.


Definitely no wax stat that I can see. Wonder if that blue-topped thingy has something to do with it?

[citronut]

there is a wax stat Ian
i can spy the end of the cable feral below the were the throttle cable goes through the bracket,

and the stat will be behind the fuel filter

the device on the front of the pump is a servo to advance the pump on cold start,

the small rubber bellows down the front of the pump have a contact inside, which when closed feed a negative to the servo, which powers it up/on

regards malcolm

[Dollywobbler]

Ah, mystery solved! I'm just used to it sitting on top all obvious like. Well, I don't think it works...

[Mothman]

Its not connected though is it Malcolm? Cant see it if it is unless your eyesight is better than mine!!

Andy

[KevR]

It's dark and rainy out there tonight so I'm not going out to look right now, but the waxstat unit on every TD I've had has been on the thermostat housing, with a cable running to the ferrule Malcolm points out, then all the way to the timing belt end where it goes through the bellows and spring and terminates with a loose cable clamp. Can't see any cable there.... Got a pic of the thermostat area? (no fuel filter there on any TD I've had - they're next to the LHM reservoir).
Haven't heard of an electrical equivalent of the waxstat on these pumps - it'd have to be pretty strong to pull that lever!
Blue-topped thingy is the stop solenoid isn't it...? Although not sure why it has two connections to it....

[citronut]

Kev this is a TZD which as far as im aware all have the plastic filter housing bolted straight on top of the thermostat housing,

and no the cabl e does not go through the rubber bellows but just to the lever at the timing belt end of them,

inside the bellows there is a contact breaker which when closed feeds a negative supply to the servo


regards malcolm

[Dollywobbler]

Not all TDs have the filter in the middle. I know Sandre's has the 'normal' filter housing bolted to the inner wing as it entirely got in the way when we did an LHM refresh on it!

Now I know the cable is there, I can give it a tug and see if it raises the revs.

[Defender110]

Now I know the cable is there, I can give it a tug and see if it raises the revs.

But like Andy has said; the cable doesn't appear to be there, just the ferrule where it should go through?

[Dollywobbler]

*stares at photo* oh yeah. That might explain it's non-functioning then! Wonder if that's a legacy of the engine swap it had at some point?

[KevR]

Kev this is a TZD which as far as im aware all have the plastic filter housing bolted straight on top of the thermostat housing,

and no the cabl e does not go through the rubber bellows but just to the lever at the timing belt end of them,

inside the bellows there is a contact breaker which when closed feeds a negative supply to the servo


regards malcolm

I've had seven TDs, four of them TZDs, and they've all had the filter on the inner wing!

You're right about where the cable goes of course – just above the bellows, not through it. Brain fade.