When I rebuilt my 142, I installed a new, original style heater control valve with the thermostatic regulating element. The valve does not operate very smoothly and it doesn't completely shut off the flow of hot water despite assiduous attention to cable adjustment and lubrication. The difficulty in getting it to close is quite noticeable and unappreciated in the summer. I would like to get something that works a little smoother and actually shuts off the flow of hot water.

I seem to recall that my 1979 242GT had a simple cable operated heater valve and I know that my 1987 745T had a cable operated valve (although all I have been able to find listed are vacuum controlled valves for the 740). Has anybody retrofitted a simple (and effective) mechanical heater valve to their 140 and if so, what did you use?

Thanks - guy with a hot right foot.

For 200 series but 100 series part has been superseded with the 9131998 which this replaces. I have no experience with this part but I am going to try one. Of course, if you replace the A/C and heat with an aftermarket unit you don't need this.

http://europartshouse.com/index.php?main_page=product_info&cPath=8&products_id=36

Did you try this replacement valve? If so, did you make an adapter to try and mount it in its traditional 140 position on the firewall or did you just connect the two hoses on the front side of the firewall together and then mount the valve more like it would be mounted on a 240?

I disconnected the lines at the engine side of the fire wall, used straight heater hose instead, and connected them to each other with a coupling because I noticed moisture on the driver side carpet and wasn't sure if it was the core or the valve. Now I can't remember which one was connected to the upper and lower port on the firewall. I bought new replacement hoses and assume it will be obvious based on the bends in the hoses. Is that true?
Thanks

On my 1971 (and I think on the 1972), the heater valve is solidly mounted on the firewall with all the hose connections being on the engine side of the firewall and the cable mechanism being on the interior side of the firewall. On the 240s which this valve seems to be the retrofit for, the heater valve appears to have moved from the firewall to everything being mounted in the interior of the car. On the 240s the valve appears to be attached to or mounted close to the heater housing. The change to the heater valve location may have occurred with the interior / dashboard changes that Volvo made to the 140 in 1973. So if you have a later model car it may not be obvious what I am going on about.

I think the retrofit heater valve can probably be made to work in the stock valve location on the early 140 cars. The primary issue is that the early 140 heater valve is mounted on a metal flange which fits into the square hole in the firewall. The flange is retained on the firewall by screws which stops it from flopping around and also seals off the engine compartment from the interior compartment. It looks like you could position the retrofit valve in this location with the hose connections on the engine side of the firewall and the cable on the cabin side. The only issue I see is that the valve hangs loose (only supported by the hose and cable connections) and you have a fairly large hole for the old valve which is no longer completely blocked off. If you have the early style valve arrangement I was curious as to whether you had fabricated some kind of flange / gasket arrangement for the rectangular hole where the original style valve is mounted.

As to the hose arrangement. On the early 140 cars hot water exits the elbow fitting on the back of the head and enters the heater valve with a piece of hose that has an offset in it.

https://www.cvi-automotive.se/en/articles/2.14829.44871/heater-hose-140-69-72

From the heater valve there is a shorter piece of hose with a couple of 90 bends that connects to the top port on the heater core
https://www.cvi-automotive.se/en/articles/2.14829.44872/heater-hose-140-69-72?q=680844

The third hose connects from the bottom port on the heater core to the long pipe along the side of the engine that runs back to the water pump housing.
https://www.cvi-automotive.se/en/articles/2.14915.44875/heater-hose-140164-69-72?q=680872

If you have an early car I think it should be fairly obvious how the hoses are connected.

I haven't installed it yet. It hasn't been cold enough here in Florida to motivate me. I am planning to this weekend though but I don't remember the differences between the two versions. Any suggestions? I guess the 240 version may be easier?

Just getting back on line after a pause so bump this.

I have dealt with the 140 heater valve for decades and know of this issue intimately.

The linkage and cables will not line up properly to completely close the valve using the controls alone on both valves I have used in 40 years. During the cold weather, a little heat leaking by is OK. During the start of hot weather I can deftly reach under the dash while driving and close the valve completely by feel alone. During the summer I am really careful about not opening the valve with controls. The linkage does not prevent you from completely closing the valve.
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Antique Swedish Steel 71 142E color V#102

I found some cable operated valves with the right size barbed fittings. The problem is the fittings are in-line which is going to make for an odd fit.

I tend to think that, as suggested, a suitable 'summer shut-off valve' may be the viable option.

Same issue on my 242 - plumbing dept. ball 1/4 turn ball valve did the trick. Shut it completely off for the 10 months of the year that I don't need heat.

And then I finally ditched the entire Volvo HVAC system and installed a Classic Auto Air system. Now A/C and heat that works as it should year round.

You should really consider a 1/4 turn plumbing valve, in addition to your heater valve - you only need to close it when the weather is warm enough for the unwanted heat to bother you, and open in when it won't.

My two cents.....after years of messing with the temp valve, sometimes I get pissed off. I do think that careful adjustment of the cable, the throw and bite can sometimes fix this. If you can't get it to work, a simple plumbing valve in the engine bay can turn all the heat off for the summer. It ain't pretty but it works.....I aint pretty either.

I was able to get a Heater Valve Repair Kit from NAPA ages ago.
NAPA part # 660-1000

I think I paid about $11 for it. It was definitely quite a few years ago, but maybe you can check that #.

I have seen those. They are actually produced by a company called Balkamp. Some Chryslers and Studebakers and other vintage stuff use a similar valve to the 140.

My valve is essentially new so I don't think a leaking seal is the issue. I think its more of a fundamental design flaw in the valve operating mechanism.

Guys;

If the HCV is "essentially new", I expect sealing and mechanism to work well (presuming it is well lubricated!)...but if it doesn't shut off fully, or works itself open, I expect it is an Bowden (control) cable issue...after lubing cable to assure there is no lost motion, check and adjust cable ends so there is no preload encouraging the control lever to spring back...sheath-clamp may also be slipping and need to be modified with barbs to assure holding sheath securely...

HCV notes: http://www.sw-em.com/Heater_Control_Valve.htm

Barbing cable-clamp:

Source: http://www.sw-em.com/checkchoke.htm

Cheers

I had a look at the Swedish Embassy site and yes, the 140 valve is essentially the same valve with the same actuating arm arrangement.

The valve actuating arrangement is configured such that the valve is fully open when the actuating lever is pointing at about 80 - 90 deg (using straight up as a 0 deg reference) and closed is achieved when the actuating arm is somewhere between 150 - 160 deg. That external spring is presumably there to assist in closing the valve.

I checked and there is no slippage of the control cable jacket in the retaining clamp on the valve body. What I can see is that the valve smoothly moves towards the closed position as I rotate the dashboard control. As the valve actuating lever approaches about 135 deg the lever becomes very hard to move further. I can rotate the dashboard control further towards the closed position and I can see the control cable proper flex out because the lever is not moving further. If I reach up and push on the control lever with my finger I can feel the lever rotate perhaps another 10 - 15 degrees and then snap shut. At this point water flow is completely shut off. That final 10 - 15 degrees of rotation of the actuating lever requires a lot of force to achieve.

I detached the control cable and manually opened and closed the valve. I observed that the external spring cannot exert enough force to shut off the valve completely and that you have to force it shut with your finger. The problem with the actuating cable is that the force it can exert on the actuating lever is defined by the Sine of the actuating lever angle. As the actuating lever approaches 135 degrees the force of the cable becomes very ineffective at achieving further rotation of the lever.

I did spray a large amount of lithium grease into the valve operating mechanism. The valve operates very smoothly up until that final 10 -15 degrees of motion which then requires a lot of force to achieve.

If the valve actuating mechanism were arranged such that cable was mounted on the bottom of the valve and pulled the valve closed, there would probably be no problem getting the valve closed. Getting the valve fully open might be more difficult; but, that is usually less of an issue.

142G;

OK so I get your point that the control linkage geometry maybe/is part of the problem...I have no answer for that but I have trouble believing that ALL 140 have a similar design issue...are you sure it is together as it should be...perhaps someone can post some pictures of an arrangement known to be unchanged from factory...

Good Hunting!

That kit will fix a leaky valve, but not one that won't shut off completely.

Ok.
I was thinking that the internal seals may have been binding up.
Is it really that mechanically complex?

Agreed!

I can get mine to shut off completely if I crawl under the dash and push up or pull down (can't remember which) on the lever attached to the cable which actuates the valve mechanism. It will stay shut for a while; but, eventually seems to work itself open.

The angle of the actuating lever in the closed position is poor relative to the cable mount. As it approaches the closed position the cable ends up exerting less force in the closed direction making complete closure of the valve very difficult.

There is a local pneumatics / hydraulics shop that happens to have a cable operated valve meant for temperature control on some other 'stuff'. The ports appear to be the correct diameter. However, the orientation of the ports is not optimal which would require some flakey looking hose fittings. It would also require a significantly longer control cable. I was really hoping that someone else had gone through this already and could say 'here is the easy drop-in fix'.

while we are going on about this.... Could you modify the cable housing mount so that the angle is better for full open/close. I'. thinking a bit of metal that is held in place with the original cable holder screw, and then duplicates the cable holder but at a better angle....nice snowstorm project.
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Patrick, '68 220 , '53 GMC 4104, '97 VW Transporter.