Volvo RWD 700 Forum

The Scantech heater control valve in my car is less than 6 months old, and it already is showing signs of seeping, or having seeped in the past, minute amounts of coolant. I want to avoid a catastrophe, so will replace it this weekend.

Have heard that the new genuine Volvo heater control valves are all plastic now. Are they better quality than the cheapo Scantech valves, though? God forbid, are they made by Scantech for Volvo? Hope not, Scantech = $18, genuine Volvo = $118 at the dealer ($60 + shipping at Tasca Volvo).
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)

The valve that the Volvo dealer got me was exactly, and I mean exactly, like the Scantech one in the car, except for the silk screened "Scantech" on the one in the car. After thinking it over for a couple of days, I returned it and the dealer was nice enough to refund all of my money, $123.xx with tax. They did not even keep the restocking charge that the receipt says they charge.

Now, will pick up one at Advance Auto, looks like the one Spasske posted, and will contact FCP to see about a replacement for the one that is, or appears to be, seeping. Will compare then put the best in the car.
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)

Just like you, I’ve been going through these things in about six month intervals. About a week ago I noticed the one on my ’88 780 was dripping so I figured I see if the local parts store (Advance) had one in stock. I figured it can’t be much worse than the ScanTech ones I’ve been ordering online. They had it in stock and it was about $15. It looks exactly like the one in the photo ‘spasske’ posted.

I just installed it yesterday so I can’t comment on its durability.
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Michael - Melbourne, Fla 1985 740 460k, 1988 780 Coupe V6 190k, 1992 745 200k

I just ordered the four seasons model from rockauto for $12 ($20 other places online). They have a good reputation. The style is a bit different They used to make the same style as the volvo but changed at some point. It works/fits the same. This is also used on many domestic cars too.

Anyone have any observations about this style?
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Paul NW Indiana '89 740 Turbo 140,000

Coincidentally, I had a near-catastrophic coolant loss last Friday. Babied it home with the heater full open, and the AC off, since I was only ~ a mile from home when the needle pegged. Let it coll, checked fluids, and added water. Ran an 8-mile test circuit with no problem, but then checked the rcoolant tank...empty!

Tried adding H2O again, and it poured out of the heater hose area behind the block, right near the heater control valve. Figured it was the hose or the valve...parked the car untill Monday, when my mechanic was open.

On Monday, dropped off the car, and gave him my armchair diagnosis (THANKS TO THE BrickBoard). He called back and said the diagnosis was right on...the valve was shot. It was available, and he replaced it with a unit that looks exactly like the one pictured here.

Thanks, BrickBoard!

Harry

1989 745GL, 192K mi

Harry, while I don't want to be the bearer of bad news, and certainly hope you have no damage: That is exactly what happened to my car last summer. Except that my water was not pouring out, more like steaming from the split heater valve.

I capped my heater ports on the engine side, and it seemed to run fine, almost. Over a couple of weeks it started drinking up lots of coolant and overheating. Long story short, the very short overheat (like yours, mine was only a mile or less from home) did damage to the head gasket and possibly the head.

While your mechanic has the car, I'd recommend that you have him do a cooling system pressure test, and a compression test on it.

Watch your car very, VERY carefully over the next few weeks. Especially watch the coolant level/condition, level/condition of the oil, and the operating temperature. Check the coolant level/condition and oil condition/level at least twice per day for the next couple of weeks. Preferably check them every time you go to start the car, and after each time you shut it off. Carry a gallon of pre-mixed coolant with you. I'm not kidding. Watch the temp gauge like a hawk.

Any, and I mean ANY, unusual symptoms are grounds for a trip to the mechanic. Even the slightest hiccup or burp from the engine, the slightest twitch from the temp gauge, the slightest hesitation that wasn't there before.

At this point, you are trying to contain and minimize any further damage. Whatever is done is done, but you don't want it to go any further if the car drinks up too much coolant and starves the head of coolant again.
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)

Looks decent--maybe it doesn't have the inherent weak spots of the Volvo design, like the paper-thin walls of the connector tube. I'm an antique car enthusiast and earlier in the spring found at a swap-meet an all brass valve, a beautiful machined work of art, that was essentially identical to the Volvo design but in a crate of miscellaneous 1940s and 1950s heater values: the vendor thought it would fit a Studebaker. He got twenty bucks for it but I am so glad I bought it. The next week the valve on my wife's '88 760T failed 100 feet fromt he driveway (unbeknownst to her) and the next morning I just happened to check the coolant--or lack of it--before she drove the car off to die. Sometimes you get lucky!

If you can cancel the order, I would. I would bypass the heater core,(remove the valve) with a piece of copper. I got mine from fcp groton. MTC, $18.00
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Post Back. That's whats makes this forum work.

That "genuine Volvo" part is a generic GM valve.

I recently purchased a Volvo heater control valve from a Volvo dealership in British Columbia for my 945T. It was identical in every way to the Scantech one I had lying around that I purchased a couple of years ago, but had not installed, except for the price - an astounding CDN$124.44. The dealership indicated that Volvo no longer made the metal/plastic one and had moved to the all plastic model.

On another note, went to purchase a coolant filler cap and they wanted over CDN$40.00 at the dealership. I subsequent saw the identical cap, made in Germany, available through a autoparts website for around CDN$14.00.

Three questions:
1. how is the quality of the "generic GM valve?" Is it better than the Scantech valves? Will it last a year or two, or even the five to eight years that we all used to figure was the life of the old, metal Volvo valves?

2. Are you telling me that the Volvo dealer is charging me $118 for a generic GM valve?

3. Do you know what GM cars it fits? If I know that, then I can try to get it cheaper from a GM dealer - Oh, wait, aren't they all bankrupt or something?
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)

The part is of superb quality: mine last a long, long time. Buy from Tasca or Borton Volvo to secure a much better price. $118 is an outrage.
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See the 700/900 FAQ at the drop-down menu above right.

Would have bought it from Tasca, but procrastinated, and now must replace Scantech valve this weekend or risk catastrophic coolant loss. Don't want to go through that again, so local dealer it is. Ordered on Monday, but Tasca did not have it in stock and I could not guarantee having it in hand by this Friday. Besides overnight shipping would put the price very near local dealer's.
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)

I've been seriously considering just putting a copper pipe fitting in that location with a couple hose clamps...plugging the vacuum line and taking the hazard away. I'm not exactly sure of the downside to that.

The downside is that the heater core will always have hot water flowing through it, not a happy prospect on a hot summer day when the a/c is struggling anyway.
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See the 700/900 FAQ at the drop-down menu above right.

It just happen to me. Valve blew apart in my hand while trying to tighten the clamp. Used 1/2 copper tube ( 5/8 OD ) but flattened it out in the middle to stop water flow. Don't need heat in Arizona for now :)

Robert