My daughter's 1984 240 has hot air coming from the heater vent at all times. I checked the heater control valve and the cable seems to close it off properly. I measured the temperature of the input and output hoses with the engine warmed up. The input hose was about 100degrees and the output was about 80 degrees. From this I assume the valve is working.

Next, I tested the vacuum system which controls the flapper doors and it was ok as far as controlling the air re-circulation flapper and the defrost flappers.

The 700-900 FAQs list a similar problem and one cause is the door which prevents air from flowing through the heater coils not closing when the controls are set for no heat. I would guess that the 240 has a similar door but I don't know where it is or how to check it.

Can someone point me in the right direction? I pray it doesn't require digging into the heater system like when I replaced the blower motor!

I haven't posted in a long time. My adult daughter now has the 1984 240 which I bought her as a high school graduation gift many years ago. The car has way over 300,000 miles and is her daily driver to work. I retired from wrenching with a new Subaru Outback. 'Not nearly so easy to work on as the 240, but I have a warranty. ( I guess I'm getting old.)

The other option is the EuroPartsHouse valve.

http://europartshouse.com/index.php?main_page=product_info&cPath=8&products_id=36&zenid=91106c2493601b5815db899994fa2c7e

You will not get the full swing of the temp lever but it doesn't effect operation in the least. All metal design and only $59.00. I have one in my 245DL and with the heat off the vents blow cold on the highway.

I have the wagonmeister part as well but it just gave up the ghost after seven years. Not a bad run but not as long as stock.

Don't even think about putting that IPD plastic valve in your daughters car unless you want her stuck by the side of the road when it blows and dumps all her coolant in the floorpans. Ask me how I know...

Good luck!

Yes, common issue.

You could try to adjust the thermostat, but after 35 years I don't bet on it being effective.

Pinch off the hose to be certain that's what the trouble is (there's no air door solution) and then visit Dave Samuels at wagonmeister.com for the premium 240 heater valve replacement.


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Art Benstein near Baltimore

Duct tape is like 'The Force'. It has a light side and a dark side, and it holds the universe together.

Can you compare the Wagnmeister valve to the one from IPD/

My apologies for giving you the advice to get the valve from Wagonmeister as if I personally know it to be better than what else is out there. My actual experience is confined to the original equipment, which is no longer in production.

I've heard there is a repro made, and IPD is selling one. Hearsay. Also hearsay is that it is junk. Dave Samuels is a long time friend I've come to trust, and again the hearsay says the result of his long pursuit of a worthwhile replacement for the original Ranco valve is the best out there. If nothing else (ask Phil) his service after the sale will exceed your expectations.

I used my last new old stock (NOS) Ranco valve 10 years ago. When a valve in one of our cars finally dies (and it will) perhaps I'll order one from Wagonmeister and one from IPD to compare and report on my opinion of each. You could do that.


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Art Benstein near Baltimore

Expert: An "ex" is a has-been and a "spurt" is a little drip under pressure.

Art-the pic.

the one I took out of an 80 has a Phillips head.

When that one failed -- I couldn't adjust the Heat in the winter. It would shut off all the way so no problem with the AC, but for the heating season it was Lukewarm of Baking.
Driving I95 from MD to NY for the hollyDaze--freeze or fry.

The screw adjuster did nothing in that case.

To the OP... yes Pinch the hose for short term fix.

To pinch the feed hose (the one coming from under the intake manifold) -- use a cheap pair of needle nose locking pliers with a short length of fuel hose slipped over the locking ends to protect the heater hose. Use only enough clamping force to close off the coolant flow. - Dave

Thanks Art, I downloaded the installation instructions and it looks doable. I don't want my daughter melting this summer. She has to drive home at the hottest part of the day. Even here in Oregon that can be uncomfortable.

Hi 240holst,

You can pinch off the flow for the summer or just do it for diagnostic reasons. I would be careful using the hose between the engine's head and the firewall bulkhead connector. This hose is the first to go of all the heater hoses because of the flexing it gets with the engine rocking on the motor mounts, and the oil soaking it can be exposed to. Pinching the hose with any tool is OK on a hose in good shape, but it might be the last straw for an old one under the hood.



These pliers are available from Harbor Freight for example. Don't know if the local auto parts stores have them.


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Art Benstein near Baltimore

Give a man a fish and he will eat for a day. Teach him how to fish, and he will sit in a boat and drink beer all day.

“...I don't want my daughter melting this summer. She has to drive home at the hottest part of the day. Even here in Oregon that can be uncomfortable...”

Pinch off the hose until you get the new valve installed. I doubt she would need the heat in the mean time.
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Current rides: 2005 Volvo S80 2.5T, 2003 Volvo V70 2.4NA, 1973 Volvo 1800ES (getting ever closer to road worthiness)

Htr control valve failure - common problem that vintage. Replacement valves are available although quality seems unreliable at best. Where I live - rarely needed heat. I cut the heater hose on the passenger side and installed a high temp ball valve from local hardware store. Would leave it shut off for 10 months out of the year. Placed valve where I could reach behind the hard plastic console side panel to operate valve.
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82 242-6.2L; '17 Mazda3; '16 Crosstrek

I'll check out the valve idea.

On the original Metal Valves there is an adjustment screw at the back of the valve. You may want to try this.

Volvo Problem Solver Advanced Edition. Section 82 pg101
****The Temp Valve is adjusted by a screw in the valve mechanism It is a sensitive adjustment, needing less than ONE complete turn CLOCKWISE(cooler).

The Valve must be in the Cold Position Stop(on the valve at the cable end) before making the adjustment. Put the TempSelector in the Cold Position. If the hose still hot or warmer than it should be you can try this adjustment. slowly turn the Screw Clockwise(no more than One turn)

If this dosen't help(hose temp still to high) then replacement of the entire valve is needed.""""

The SCREW is in the Back of the Valve... A short Stubby screwdriver can be used.

Thanks, I'll give this a try.

It sounds like the heater valve isn’t closing. Common problem on older bricks. As a test try pinching the hose off good and tight and see if the problem goes away.
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Current rides: 2005 Volvo S80 2.5T, 2003 Volvo V70 2.4NA, 1973 Volvo 1800ES (getting ever closer to road worthiness)

Hi,

It is more like to be leaking by. If it’s original valve, most definitely, and if it’s the same style, it gone out adjustment or calibration. The seal inside cannot last for ever.
Either way it’s done, because they have not been available for quite some time. Or the ones around are at price you cannot believe.

It doesn’t take much hot water to really heat up the air, when the outside air is already more than half as warm that you would get this time of year.
It probably has been doing this all through the winter but it’s not as near noticeable when a little feels good!

The 100 down to 80 means some heat went some where and it is flowing, even at a trickle!
Pull the left cover and feel the two hoses. One for sure or both should not be hot, if its shut down completely.

Since it’s summer! You could bypass the valve by connecting the two outside hoses together, but you might hate yourself come this fall!

Check with Wagonmeister.com and see if he still offers a plastic one today!
He was having supplier issues the last I knew and that was a long time ago!
There are other metal valves being offered, I cannot remember the sites, but a search can help.

Good luck,

Phil

Wagonmeister still offers a valve at $150. IPD has a valve with a new bracket for $50. The IPD valve seems like more work.