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Chevrolet Repair/Heater Control on C2500

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Question
QUESTION: I have a '95 chevy 2500 2wd it was a diesel and prior to buying this truck a crate 350 was installed. Just recently replaced radiator and heater core I have plenty of anti freeze thermastat opens but no heat. I've checked online for the location of the heater control valve, but can't get a defintive answer to where its located please help?

ANSWER: HI BOB,YOU TRUCK MAY NOT HAVE A HEATER CONTROL COOLANT VALVE. WARM THE THE TRUCK UP AND SEE IF BOTH HOESES GOING TO THE HEATER CORE ARE HOT.IF ONLY ONE IS HOT THE HEATER CORE IS PARTIALLY PLUGGED. REMOVE THE HOSES AND BACK FLUSH THE HEATER CORE. IF BOTH HOSES ARE HOT THEN SOMETHING IS GOING ON UNDER THE DASH,SUCH AS BLEND DOOR NOT OPENING AS IT SHOULD..GOOD LUCK TOM AND LET ME KOW HOW THIS GOES FOR YOU..

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QUESTION: What's the chances of there being AIR in the cooling system since I just replaced the heater this past Saturday? All other parts seem to be working.

ANSWER: HI BOB I WOULD THINK BY NOW ANY TRAPPED AIR WOULD OF WORKED ITS WAY OUT OF THE SYSTEM..LET ME ASK YOU ARE BOTH THE HEATER HOSES HOT ??? THEY SHOULD BE IF THE HEATER CORE IS NOT PLUGGED..IF THE HOSES ARE NOT HOT AND YOU SAID THIS WAS A DIESEL ENG THAT BEING SAID THIS HAS A HUGE COOLING SYSTEM IN IT..WHAT DEGREE STAT ARE YOU USING ?? YOU SHOULD HAVE 195 DEGREE. SO IF BOTH HEATER HOSES ARE HOT THEN FOR SURE THE PROBLEM IS IN THE DASH AREA..A BLEND DOOR IS NOT OPENING ENOUGH TO ALLOW THE HOT AIR TO ENTER THE CABIN..BUT IF THESE HOSES ARE NOT HOT,HOT THEN THE COOLING SYSTEM IS NOT REACHING ITS CORRECT TEMP. I DO NOT KNOW HOW MUCH YOU HAVE BEEN DRIVING THIS BUT IF MORE THEN 100 MILES I WOULD SAY ANY AIR IN THE SYSTEM IS GONE BY NOW..LET ME KNOW ,OH, IF THE HEATER HOSES ARE NOT HOT AND YOU HAVE THE CORRECT STAT TRY PARTIALLY BLOCKING OF THE FRONT OF THE RAD AND SEE IF THIS HELPS...GET BACK TO ME GOOD LUCK,,,TOM

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QUESTION: Tom thanks both lines going to heater core are hot. Correct stat is in. Replaced the heater core on saturday wife drives the truck. She had no heat on Monday. After the core was installed did some runnin' around had plenty of heat, usually the heat ran you out now nothing. Temperture controls are working they switch to proper settings excluding heat. So if the blend door motor is out where exactly is that located? And would that just got out right after replacing the heater core? Is that a quick fix the wife is freezing here in Ohio lol. This truck had a diesel now has a crate 350 with after market temp guage and it's dead on.

Answer
HI BOB,,WELL YOU HAD THE DUCT WORK OUT OF THE LOWER PART OF THE DASH,THE DOOR IS WHERE THE HEATER CORE SITS..IS IT POSSIBLE THAT THE DOOR IS COCKED ON ITS PIVOT NOT LETTING THE DOOR SWING PROPERLY ?? DI IT GO BACK TOGETHER OK.. AS FAR A S A QUICK FIX THERE IS REALLY NO WAY OF GETTING AT THIS UNLESS YOU CAN FEEL THE DOOR ACTUATOR ROD FROM THE DUCT WORK ??? SOME YOU CAN AND SOME YOU CANT. BEING TAHT THIS HAPPENED AFTER THE CORE INSTALLATION I THINK THIS IS WERE THE PROBLEM LIES.. YOU SAY BOTH HEATER HOSES ARE HOT SO WE KNOW THERE IS HEAT TO THE CORE JUST NOT GETTING INTO THE CAB..DID YOU HOOK UP ALL THE CONTROLS OK UNDER THE DASH ?? [JUST A QUESTION] TRY TO MOVE THE ACTUATORS THAT YOU CAN REACH BY HAND,ALSO USE A FLASHLIGHT AND WATCH WHEN YOU MOVE THE CONTROL HEAD  SWITCH OR LEVER FROM COLD TO HOT UNDER THE DASH,THIS IS THE CONTROL ACTUATOR YOU ARE AFTER..SEE IF IT MOVES OR IF IT STARTS TO MOVE AND THEN STICKS ON SOMETHING..ALSO SOME OF THESE CONTROLS ARE ACTUATED BY VACUUM,DID YOU HOOK ALL THE LINES UP OK ??? GOOD LUCK TO YOU AND LET ME KNOW HOW YOU MAKE OUT,,,TOM...

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TOM SHEETS

Expertise

PLEASE READ ALL OF THIS BEFORE ASKING ANY QUESTIONS. IF THIS CHEVY SECTION IS MAXED OUT.YOU CAN REACH ME IN THE OLDS/BUICK SECTION. Will answer questions from 6:00am to 10:00pm all days [EST][[[ NO DIESEL OR PAINT QUESTIONS]]] will answer all 1965 to present QUESTIONS ON ALL GM'S on mechanics of these cars. Keep in mind i am not there in person i am going on what you are telling me !! PLEASE IF ASKING A QUESTION GIVE ME AS MUCH INFO AS POSSIBLE. THE MORE THE BETTER. SUCH AS YEAR,MAKE,MODEL,ENGINE SIZE. THIS WILL HELP ME HELP YOU. I will not be able to answer all questions because of some situations that i would really need to be there and see things for myself,such as electrical issues. In many cases i would need wiring diagrams. I can also give you an estimate on what the cost would be at our repair shop as an idea to help you. Keep in mind that my answer is ONLY MY ADVICE,ck with your mechanic as well.. >> THANK YOU, TOM..

Experience

I have been a ASE certified master mechanic for over 30 years and certified IN ALL 8 CATEGORIES,[engine repair,engine performance,auto trans,manual trans,clutches,steering and suspension,brakes,electrical systems,heating and air/cond. I am also a state CERTIFIED inspector for over 30 years. I do computer work [pcm]fault codes,pcm flashing,state inspection monitor readiness,repairs on exhaust,fuel service,[injection and carburetor,] charging system problems, running issues,alignments,frame problems,tire balance,struts and of course standard and anti-lock brakes.

Organizations
nys state auto repair industry and ase group.

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N/A

Education/Credentials
high school,4 years of tech school,and many many hours of auto training with many gm classes and aftermarket training classes..

Awards and Honors
ASE MASTER TECH CERTIFIED IN ALL 8 CATEGORIES.NYS INSP LICENSE AND A/C CERTIFIED

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MANY CUSTOMERS IN OUR BUSY SHOP.

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