corbith

Let me start by saying that I have searched this forum and thought I had an answer but am now thoroughly confused...

I found coolant on the passenger side of the car when running a power wire under the carpet back to an amp for a mild stereo upgrade. Odd thing was the carpet was not wet, just the padding under. Based on research here, it appears this is most commonly from the heater control valve. After reading many posts, I thought this was the part I needed: Motorsport! Heater Control Valve, 79-83 280ZX Without A/C - The Z Store! Nissan-Datsun 240Z-260Z-280Z-280ZX-300ZX(Z31/Z32)-350Z-370Z Parts even though it says without A/C, many of the posts indicate it's really meant for those without automatic A/C. For reference, I have manual A/C in my 82 NA. So I placed an order and received an email from someone at Motorsport indicating this part is truly for the rare 280zx's that do not have A/C at all and wanted to confirm it is the part I actually need. So now I am confused as to which part I actually need, following is the only valve I could find that indicates it is actually for manual A/C: Datsun Nissan 280zx Heater Control but 189.99 for a used part with a core cost of 100 seems like robbery to me.

Can anyone who has manual A/C and made this change offer any guidance? If the later of the two is the only option, is it actually safe to just bypass the heating system all together? Ideally, I would like to properly repair the car but not at almost 200 for a valve given the car does not get driven in the winter. I also read from another source that if you bypass the heating system on the side of the engine there is a significant risk of overheating, is this true?

NismoPick

Read:

https://www.zdriver.com/forums/280zx...l-valve-35270/

corbith

I did read that post and those linked out to from that thread. Which is why I thought I was ordering the right part until I got the email from Motorsport. So do I need part # 27116-P6500? If so that is what's pictured on Motorsport's website. However, in the email they mention they do not keep the part in stock and order it on an as needed basis but found one on ebay for 39.98 shipped Genuine Nissan 1979 1983 280ZX 280 ZX Heater Control Valve Non Auto Air New | eBay .

NismoPick

^^^ All of those are the same one...

Any of those will work... You don't NEED to replace it with the a/c one involving the coil running to the heater core.

corbith

Thanks Nismo, I thought I was clear until I got the email from Motorsports, that is what confused me. I purchased the one on ebay. Do you know if I should be able to replace this without removing the entire dash?

NismoPick

You can, but it's tight in there. You'll probably need to use a stubby phillips screwdriver to get the mounting screws out.

corbith

Great, thanks again! I'll give it a try without removing, just hate to go through it as it looks like a nightmare.

icice9

remove the passenger seat to give you more room to work with.. its a tight area to work with but its not impossible.

corbith

Thanks for the tip ice, will remove the seat.

corbith

Interesting, I just got another email from Motorsport indicating that part could work with modification. However, I already ordered it from eBay so I canceled the order with them. Nismo or Ice - have either of you had to replace this part? If so, did you have to do any modifications to make it work?

icice9

read the link again that Nismo posted.... everything i did is all there..

corbith

Just re-read, seems you had to cut the coil and mentioned different screw locations. Did you have to create new holes to screw into or is it just seated a bit different than the original?

icice9

the holes were already there... just line up the new choke valve inlet and outlet with the old one and you'll see that its hole locations are different then the old one... screw it in.. adjust the cable, and adjust the push/ pull pin and your good.

corbith

Great, thanks! You make it sound so simple though, hope it is once I get to it.

pnoyslimm

im having the same issue and (after reading numerous threads) still confused about which control valve to get.

i have an auto climate control and have done an a/c delete. i took out the vac pump and ran the two vac lines running out the firewall to vac ports on the intake.

would i still have to get the heater control valve for auto or can i use the manual control valve?

i did find a heater control valve for auto on Rouckauto for $20.

NismoPick

If you have the auto climate control, you need the auto climate valve (actuated by vacuum).
If you have the manual climate control, you need the manual climate valve (actuated by mechanical slider).

pnoyslimm

does replacing the heater control valve involve removing the dash?

pnoyslimm

thank you for clearing that up.

...im what they call "dyslexic."...

NismoPick

Depends on the size of your hands and arms, and how long you like working upside down / on your side under the dash.

First time dash pull is pretty time consuming, but getting everything out of the way makes the valve change easy.

borini63

It's only 8 screws and your dash is out after removing the radio console and the under dash panels.....wallah everything is exposed!!

zedsdeadbaby

Pretty simple to remove the dash, and if you do, you can find this:



Thats a vacuum distributor filled with rust after an old heater valve gave up. Even after replacing the valve, this was blocking me from having any vacuum to the valve, and I had no heat.

FricFrac

Removing the dash sounds like a pain but it's pretty easy. Do it!

pnoyslimm

i got to the heater control valve without removing the dash, just the stereo.

i have girl wrists and long skinny fingers so it was a easy for me.

i didnt replace the valve yet, i just bypassed the coolant line. i got tired of

cleaning up the puddle on passenger floor and refilling the coolant a 2x a day.

MetalMakkusu

NismoPick and icice9,
Thanks for the shared information. I recently purchased a 82 280ZX and the water **** was leaking really bad. I found about the three parts today (27116-P6500, 27116-P7100 and 27116-P7400) and that the P7100 has been discontinued and that is the one that is in my car.



The copper wire you guys are telling us to cut is the one inside the red circle, correct? (It is the only one I see).

What does that regulate ? it is no problem for me to cut it, right ? I know icice9 mentioned in the other post there is no problem and that the cold and hot air work right.

The new one that I am buying is the 27116-P6500 and I am getting it from a local Nissan Dealer and looks like this



Thanks guys! you have saved me. I cant wait to fix my car and get it running. I am very excited about this buy.

icice9

thats the capillary tube that i ended up cutting off., i cut it back as far as i could reach it.. im not sure what that tube did.. the replacement should work fine.. just have to mount it on different mounting points.. you will have to adjust the push /pull cable once you install it..

heres the link to the original post. https://www.zdriver.com/forums/280zx...roblems-22982/