Heater control valve stroke

[dmwhiteoak]

My heater is not working and I don't think the heater control valve is opening fully. The lever only moves half way up the controls but looking where the cable connects to the valve I don't have alot of travel available with the cable. Do these control valves malfunction to where they don't open fully. Any help would be appreciated. By the way, today it was 97 deg but just trying to get this resolved before winter sets in. Thanks. Dennis

[azygoustoyou]

the valves are suppose to be adjustable. You have to take them off to adjust them. Do you have a manual.

[dmwhiteoak]

Yes, I have two and only one shows how to remove it. Not real impressed with either one. Dennis

[azruss]

several things to check out. 1st, crawl under the dash and see how much motion there is in the valve lever. In many cases, the sheath clamp is loose and the sheath is moving and not the cable or valve. you should be able to move the valve by hand by un-clamping the cable. this will allow you to see the total length of motion. you can also see if you get heat. There are 3 adjustment holes on the arm. the top one gives the greatest movement. Since the lever is only moving thru half its motion, i would focus on the valve.

[dmwhiteoak]

I checked the valve last night and this is what I found. The cable sticking out of the sheath was about 1/2 inch. That is all the travel in the cable. I unhooked the cable and could move the the lever on the valve by hand only as much as the cable could. That's only half way up with the control lever. No change in heat whatsoever. Maybe I will pull it out and flush it. Is what the valve does is regulate the water flow through the core? If so halfwayshouldhave at least been warm.

[azruss]

this is old school heat. the valve just controls water flow thru the heater core. I know there isnt much travel between open and close, but should be more like 1" give or take. If you look on the side of the round housing, you will see a slot with a pin in it. That pin slides back and forth in the slot as the valve opens. If the pin isnt traveling the full length of the slot, then it isnt opening or closing fully. I can almost promise you if you restore full travel to the valve, it will leak. try spraying some lubricant in that slot and under the lever and work it back on forth to see if you can restore travel. if you manage to bring the valve back to life without it leaking you will go down in Fiat lore as a god

[dmwhiteoak]

Will give it a try. Thanks. Dennis

[Eastlight]

Bought 2 (+ one spare) heater valve gaskets anticipating removal of valve and checking the flow because my heat was constantly ON and it is quite warm even with the top down.
Glad I checked the Forum and found the suggestion about lubricating the valve pin/slot. Tried a little WD-40 and it freed the valve so it has full travel now.
However, afterward I lubricated the same plus the cable end with a little lithium base high-temp wheel bearing grease because WD-40 will dry and gum up after awhile.
Just finished the project with out removing the valve but haven't tried it out on a road test yet. If you want to see a tight space, try messing with the valve in a Fiat equipped with air conditioning. 6'2" upside down in the passenger seat trying to fit hands between the condenser and the valve is no easy feat.

BTW: I'll never purchase anything from International Auto Parts, not after the terrible way they treated me when I called on two occasions to find out what happened to my order. Now I started dealing with Auto Ricambi in Texas who are very accomodating and a little less expensive that IAP. The only item I found that was over priced was their K and N Oil Filter, which I use and Ricambi lists for $16 + change. The local NAPA sells the same filter for $9.99.

Thank you for the valve lube suggestion.

[rlux4]

It's true that you can sometimes find a common part cheaper at a national chain than you can at a vendor. But that makes sense, the national chains are buying in much greater quantity, so are getting a lot better price. As an example, I sell and install replacement windows, Lowe's or Home Depot sell a good window also, but there's no way I can buy a window at the price they're paying, I'm buying hundreds, they're buying multiple thousands. The advantage I have is service. The same can be said about Auto Ricambi. They always give excellent service, and they'll have parts that NAPA won't.
Ron