Would This Heater Control Valve Work On A Late X With A/C?

Dan Sarandrea (Phila)

Waitin' On Parts...
From a Maserati BiTurbo:
s-l500.jpg


https://www.ebay.com/itm/Maserati-Biturbo-VACUUM-OPERATED-HEATER-VALVE-315520030/173160466958
 
Unlike the flaps directing airflow on the late model A/C cars, the heater valve is cable operated (not vacuum operated), so it would take a fair bit of work to make use of the Biturbo unit.
 
Unlike the flaps directing airflow on the late model A/C cars, the heater valve is cable operated (not vacuum operated), so it would take a fair bit of work to make use of the Biturbo unit.
Ah OK nevermind :)

I was browsing this seller's offerings (mostly Maserati BiTurbo stuff) and noticed a lot of BiTurbo parts at least superficially resemble stuff from the FIAT parts bin. Then I saw this valve and thought hey that vaguely reminds me of the one on the A/C cars which is unobtanium anymore. But yeah comparing with the real one that Jeff posted, the action is wrong and the angle is wrong. Other than that it's a perfect fit LOL :)
 
I have poked at this issue a few times searching the innerwebz for visually similar valves. I have never come across a clone of the Fiat valve, but here are a few candidates. These would surely need adaptations, but they are cable operated and have right angle input and output tubes:

4Seasons/Everco Heater Control Valve Part 74637

Four Seasons 74662 Heater Valve

FOUR SEASONS 74850 Heater Valve

I have never owned an AC equipped X, so I really don't know if these are even close in size, just somewhat similar in form and function.
 
That valve is the same as Volvo 740/760 - can be had for $10-15, but as pointed out it won't work in stock configuration. I used that valve in the heater hose to the branch pipe.
 
I just replaced my heater valve with a new one from M W B, they don't always have the part, but apparently have a fabricator to replenish stock from time to time. The swap is in in tight confines but otherwise quite simple. The hardest step is getting a good "burp" from the radiator. I wouldn't' bother attempting a substitution.
 
The heater valves for non-A/C cars can be found. Late model cars with A/C uses a different heater valve; did you get an A/C or a non-A/C heater valve from MWB?
 
I used one like the Four Seasons one shown above in JimD’s post for my AC car. I had to make a small bracket to flip and hold the wire sheath to get the travel correct.

It sits where the OE one was but is not attached to the bracket anymore, instead relying on the hoses for support which is more than adequate (I hope)
 
Mine was non-AC. The swap was intuitive, even I could do it and my skills are just spin-a-wrench.
 
The closest available match is this Ranco valve. While there is some difference, including diameter of the hose inlet, it could be made to work with some mods to the attachment area and the cable attachment. Top is the original AC type heater valve.
ranco_replacement.jpg
 
One non standard option is the VW heater valve from early water cooled models, for about $3. It isn't a direct fit and will need a little adaptation. The main difference being it is straight, not 90*. However it has a built in support that mounts the actuator cable assembly (outer sheath and inner cable) so there is no need to actually mount the valve to anything (it is made to work 'free-standing'). Therefore the routing of the hoses is all that needs alteration (for the straight through design). But the hose sizes are correct, it is made of a type of plastic so it will never rust/seize, and it is available anywhere for very little money. VW part number is 171819809E (or any of its derivatives).

vw-mk1-heater-valve-2711.jpg
 
I used one like the Four Seasons one shown above in JimD’s post for my AC car. I had to make a small bracket to flip and hold the wire sheath to get the travel correct.

It sits where the OE one was but is not attached to the bracket anymore, instead relying on the hoses for support which is more than adequate (I hope)

Which one, Karl? The 74850, or the 74637 or the 74662? I'd lean towards the plastic body version. I might as well do this while I'm doing the heater core....
 
I used a plastic bodied unit. The one I used wasn’t branded as Four Seasons, these assemblies are not made by Four Seasons they have just managed to be the source most identified with them. I bought mine based on price on Amazon, I bought a few different brands and variations of valves and found they were the same parts (L or straight configurations).

The valve is the same on both of the part numbers you showed, one can also find it without the sheet metal brackets. I ended up making my own bracket which I cannot find the pictures of (ugh), In the spring I can pull the part to show what I did. I flipped the steel actuator arm on mine to better match the cable motion relative to the operation of the ball valve inside. I liked the round post on the arm versus the bent steel arm some of them used as it allows the end of the wire to rotate as the direction of motion changes.

This is the one I started with:

2FD9C21A-9EF1-4DCB-8947-0FD24B293A0E.jpeg
 
Thanks Karl

I had pretty much assumed any plastic bodied "L" valve would be essentially the same part, with just variations in bracketry & offset of lever. I bought the MTC valve, since you know it works. On mine, I have the remote valve to govern heat, I just want to change this or mine will definitely leak.
 
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This thread got me looking into options, there appear to be rebuild kits out there for these Ranco valves. I have a spare A/C box with a likely bad valve in it, maybe I’ll try rebuilding it…
 
Just went through this and here is what I did.
 
Alternative that does not require rerouting of cable:
 
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