Z31 want to force watercock shut

[bcar240]

In research I have heard found a lot of people talking about ziptied watercocks (that sort of sounds dirty...) to prevent heat leaking from the vents. Mine does not have this yet, but I have given up getting the HVAC working for the summer and I would like to just ziptie mine shut to prevent the air bleeding through the vents at high speed from being scalding hot. I have tried to ziptie it in both positions, but the air still seems to be hot, so I just wanted to confirm which way I should be doing it. Should I secure it so it can't move from it's resting position (car off) or in the actuated position?

The vacuum line and source at the watercock appears to be in good shape and functioning, I'm guessing the actuator is just shot on it.

[evildky]

most of these issues re fixable, sometimes the bashpot just stick, and sometims you simpl need new vac hose

the resting position for the heater watercock is the open position, hence the problem, you'd want to close it if this is the routs you go, and if yours is rusted soid they are on every z31 and pretty easy to swap out

[bcar240]

Sorry for the slow response, I did fix the issue by ziptieing the valve in the "actuated" position like evildky suggested, thanks for that info. I just had to cut it loose again the other day to get some heat, lol. It's confusing me now because the valve is working ok when actuated manually, but the vacuum system also seems to be in good shape. I can hear air pressure changes in the vacuum system when I open and close the valve it with the engine off. I am wondering if there is something up with the HVAC unit not commanding it open.

[evildky]

have you checked all the dashpots? most failures are a cracked or simply stuck dashpot under the dash, the controls vary quite a bit for trim and year ranges.

[bcar240]

That's probably the issue, now that you mention it. It would make sense because everything at the watercock seems to be working properly. I know there is a leak under the drivers dash because I can hear a depressurization sound from that area when I shut the car off. I am going to do a lot of work on the HVAC soon, and will see if I can track that down. Thanks!

[AZ-ZBum]

Sorry for the slow response, I did fix the issue by ziptieing the valve in the "actuated" position like evildky suggested, thanks for that info. I just had to cut it loose again the other day to get some heat, lol. It's confusing me now because the valve is working ok when actuated manually, but the vacuum system also seems to be in good shape. I can hear air pressure changes in the vacuum system when I open and close the valve it with the engine off. I am wondering if there is something up with the HVAC unit not commanding it open.

Ummm... THat would be impossible as with the engine off, there would be no vacuum to operate anything.

[evildky]

I assume he means he can manually work the valve on and off by hand.

[bcar240]

I assume he means he can manually work the valve on and off by hand.

Right, I meant when I press the valve open/closed by hand I can hear it moving air in the vacuum system.

[evildky]

you shouldn't hear air moving except at the dashpots and an open vac line

[bcar240]

hmm, I can hear some muffled noise from the valve itself and what I think is coming from the vacuum pump in the front right corner of the engine bay. They sounds internal, not like hissing through a leak, but it's worth another look before I dig into anything major.

[evildky]

the valve itself has a dashpot, I expect to hear it move air, the right front conrner is your charcoal canister, I suppose you might hear a bit fomr it. That being said that means you have no vac leak, which means your problem is either incorrectly hooked up vac lines or s stuck dashpot under the dash, a vac pump shhould free it up.

[bcar240]

So if the dashpot is stuck should I disconnect it and put vacuum on it directly to break it loose?

[evildky]

get under the dash and locate the dashpots, hook a vac pump to them one at a time and pull vac and see if they move, in my experience a little extra vac from a hand vac pump pops them loose, ymmv