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Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

I want to replace the heater control Valve on my 1992 740 Turbo. I was looking at the PEM one but it is nit all metal. I have not been able to currently find find thst is constructed solely of metal. Any ideas here? Thanks.








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    Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

    There used to be an AC Delco part 15-5320 that was all-metal. The OEM volvo part WAS originally all-metal (https://ebay.jcwhitney.com/prodimages/cld/420x420/1602334690-16263422_1.jpg) and was later revised to be half plastic.

    I'm debating getting some kind of industrial 12V electric solenoid because I really don't trust these plastic heater valves.


    However... the turbobricks guys have a nifty "bypass" style valve that seems to reduce head temperatures that might be worth replacing every 0-5 years. https://forums.turbobricks.com/showthread.php?t=246617&highlight=heater+valve+delco&page=6

    If you go with an assumed failure time of 3 or 4 years, I think you would be okay using all plastic. Still, I agree with you in disliking these being made of plastic.

    Cheers,
    Will








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    Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

    You'll be fine with to one your looking at.








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      Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

      Sorry to jump on to this post with a question.
      I am currently replacing my heater valve. The failing unit doesn’t have a vacuum line connected to it and I am wanting to install the line. I can not verify the vacuum line source on the firewall. If you could shed some light I would be very thankful








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        Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

        If you have a system like my 940 (Euro spec base model) everything is very simple - the heater control valve is operated by a wire from the control dial on the dash. Perhaps you have this arrangement?

        Ian F








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          Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

          The car in question does not use a cable, it uses a vacuum line that comes from the heater system. It is activated when the ac is turned in to eliminate hot coolant from the cabin. I’ve pinpointed the hose as marked with a grey stripe in diagrams. I just can’t seem to find where it comes through the firewall. Previous owner has removed said grey striped vacuum line.








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            Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

            The vacuum hose for the heater valve should go through the firewall about 6"-8" below the heat core nipples in a grommeted rubber sleeve. If you're lucky you'll find a stub of hard plastic tubing there. The other end will be at the heater control panel above the radio. If the original owner ever had the hose come loose off the heater valve they can sometimes melt against a hot manifold or block.
            --
            Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now








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              Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

              Thank You








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    Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

    Best of course to avoid the original design that was half metal where the brown bakelite-looking plastic eventually got brittle and the neck would snap. A few places seem to still sell this design under the MTC brand name.

    The newer Volvo all black plastic design is far better and does not have a bad reputation. They're solidly built and don't look like the necks will get brittle and break anytime soon. To see what the genuine parts looks like, check out Volvo p/n 1259327 at FCPEuro (https://www.fcpeuro.com/Parts/?keywords=1259327). Note that FCPEuro (and others) also carry an identical looking one sold under the ProParts (Professional Parts) Sweden brand name that is considerably cheaper, less than half the Volvo price. It very much looks OEM quality (as claimed on some sites), and is quite possibly from the same manufacturer Volvo uses. I have used the ProParts ones twice now and am totally happy with them. FCP, with their lifetime gauarntee, learned long ago not to carry inferior quality aftermarket parts and would have stopped selling them if they thought they were a problem. The same design is sold under other brand names, but I can't attest to them being 100% identical.

    Note that the vacuum line attachment is at a different orientation from the original, pointing downwards. Volvo has a 90 degree rubber elbow that's meant for the job. I bought one and didn't need it, in fact it didn't fit snugly, leastwise on the ProParts one. What I've done is simply use the original rubber sleeve and turn it around to get a snug fit on the nipple, perhaps adding a drop of RTV part way down the vacuum line to help secure it from accidentally being pulled off (do not get any in the vacuum tube itself). The existing vacuum line will be a bit short for the job, so in order to prevent it from kinking I slip a rubber tube over it for added support at the bend.

    For your emergency kit, I advise getting a couple of suitably sized barbed plastic plugs from a plumbing store (used with PVC/PEX). In case of a heater valve, heater hose or heater core failure, you can cut out the heater valve and the neighboring return line from the heater core and simply plug them. The pressure isn't that great so a properly sized barbed plug will hold, but if you're smart you'll pack a couple of ring clamps in your kit for safe measure.
    --
    Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now








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    Best heater control Valve for 1992 740 Turbo. Prefer all metal 700 1992

    I looked for all metal for my 940, but was unsuccessful. Some have partial metal, but I have not seen an all metal one. Frankly, I don't think all metal is an important feature.







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