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Oldsmobile/Buick Repair/1985 buick riviera

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QUESTION: I have a 1985 buick Riviera.  It is an 8 cylinder with front wheel drive.  It has electronic heating and air conditioning control on the dash (you set the temp. and the system keeps it at that temp.) I recently discovered a radiator leak.  It couldn't be fixed so we bought a brand new one and put it in. Also installed new radiator hoses and a new thermostat.  I am getting cold air from the air conditioning but not getting any heat from the heater.  Both heater hoses seem to be equally warm.  Connected to the shortest heater hose is an electrical solenoid.  Wires are connected to it and the contacts are nice and clean.  Could it be malfunctioning or does it not have anything to do with heat?  Any advice you can give will help.  Also have the dash apart and all heater and air conditioning doors seem to be opening properly.  Heater core fins look really nice and clean from what I can see.  Of course, that doesn't mean the core is good on the inside.  Thanks.

ANSWER: GOOD DAY RONALD, THIS ELECTRIC SOLENOID YOU ARE TALKING ABOUT IS CALLED A HEATER CONTRL VALVE. THIS WILL SHUT THE SUPPLY OF HOT COOLANT GETTING TO THE CORE.. IF THIS VALVE IS NOT OPENING WHEN IT IS REQUESTED TO DO SO YOU WOULD HAVE LOW HEAT. THE MAIN REASON OF THIS VALVE IS TO STOP THE FLOW OF HOT WATER GETTING INTO THE CORE WHEN THE A/C IS ON. KEEPS THE EVAPORATOR COOLER... CAN YOU CK BOTH THE HEATER HOSES [AFTER THIS VALVE ???] IF THE SYSTEM IS WORKING CORRECT THE HEATER HOSES SHOULD BE JUST AS HOT AS THE RADIATOR HOSES. IF ONLY ONE IS HOT GOING TO THE CORE AND THE OTHER HOSE IS NOT AS HOT THIS IA A PARTIALLY PLUGGED HEATER CORE...IF SO REMOVE THE BOTH HOSES ENGINE SIDE AND PUSH YOUR GARDEN WATER HOSE INTO ONE OF THESE HOSES GOING INTO THE CORE AND FLUSH IT BOTH WAYS. SEE IF THIS HELPS..DID THIS HAPPEN AFTER THE RADIATOR WAS REPLACED,IF SO IT DOES SOUND LIKE SOMETING IS PARTIALLY PLUGGED...LET ME KNOW MORE ON THIS IF YOU CAN OR IF I DID NOT ANSWER THIS TO YOUR LIKING..GOOD LUCK TO YOU,,,TOM...

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QUESTION: Thanks Tom for your quick response.  I am doing some further checking and will get back to you.  The heater problem was there before we replaced the radiator.  Have most of the dash removed and all of the heater doors (Valves) seem to working properly.  The heater core fins from under the dash look very clean.  I know that doesn't mean that it's that clean on the inside.  Really don't want to have to remove the core if not necessary.  I haven't seen any movement on the heater valve yet.  I did flush the core, but just pouring water through it.  I did not use the water hose, but, I guess I might have to.

ANSWER: HI RONALD, YES TRY TO FLUSH THAT OUT WITH THE GARDEN HOSE THAT HAS SOME FORCE BEHIND IT. THEN GET BACK TO ME ON WHAT YOU FIND AS FAR AS BOTH OF THE HOSES GETTING HOT OR NOT AFTER THE VALVE.. GOOD LUCK TO YOU,,TOM

---------- FOLLOW-UP ----------

QUESTION: Hello again Tom.  Well I took the garden hose to the heater core and really gave it a good flushing.  Water came out nice and clear and seemed to be flowing through well.  We still don't have any heat.  Both heater hoses seem to get pretty hot with engine running.  I ordered a new heater control valve but, ours has an electronic solenoid mounted to the top of it, and no one seems to know anything about it.  I am assuming if that valve does not open to let the engine coolant flow through, it can cause no heated coolant to flow through the heater core.  The wire connector going to the solenoid has juice to it.   Any chance the solenoid can be bad?

Answer
HI RONALD, YES THE SOLENOID CAN GO BAD,,BUT I DO NOT FEEL YOUR PROBLEM IS THE HEATER CONTROL VALVE. IF IT WERE THIS VALVE THE HEATER HOSES AFTER THIS VALVE WOULD NOT BE HOT..YOU SAY THEY ARE HOT.. THIS TELLS ME YOU HAVE GOOD CIRCULATION TO THE HEATER CORE AND BACK OUT...SO IF THIS IS THE CASE AND THE CORE IS GOOD AND HOT THE ONLY THING LEFT IS A BLEND DOOR FOR THE HEATER SIDE AND COOLING SIDE IS NOT OPENING ALL THE WAY TO THE CORE TO RELEASE THE HOT AIR FROM IT TO COME INSIDE THE CABIN..ONE OF THESE DOORS ARE NOT OPENING ALL THE WAY OR AT ALL...BUT IF YOU WANT TO CK THIS VALVE [HEATER CONTROL VALVE]--BY PASS IT. REMOVE IT FROM THE HOSE AND RUN IT DIRECT WITH A ANOTHER SECTION OF HOSE..IF IT HEATS UP LIKE THIS, THE VALVE IS FOR SURE BAD..BUT KEEP IN MIND YOU ARE SAYING BOTH OF THESE HOSES ARE HOT...GOOD LUCK TO YOU AND LET ME KNOW HOW IT GOES FOR YOU,,,TM

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TOM SHEETS

Expertise

Can answer all questions pertaining to mechanics of GM cars from 1965 to present. I will answer questions from 6:00 am to 10 pm est.. I will not take diesel or paint questions. If this olds and buick section is maxed out you can get to me in the chevrolet section...

Experience

I have 30 plus years experience in servicing these cars. I can answer questions on carburetor, fuel injection,ignition systems, suspension, brakes and abs, cooling systems,a/c and heater,manual transmissions, rear differential and electrical system,charing system and battery. I am a Master ASE certified mechanic in all 8 categories: - Brakes - Heating and Air Conditioning - Automatic transmission - Clutches and Transaxle - Engine performance - Engine repair - Electrical - Steering and suspension I am certified for NYS inspection and clean air insp.

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ASE

Education/Credentials
I am a Master ASE certified mechanic in all 8 categories (see above) I am an Air Conditioning/Freon recycling specialist with ASE. I have at least 4 years of technical training and many hours of continuing education.

Past/Present Clients
many customers in our busy shop for the past 30 plus years

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