1995 Fleetwood little or no heat

[Anthony C]

The next issue is no heat. Two things I noticed. A Leak in the radiator and the heater hoses are not hot one is warm and one not so much. 

Seems like a clogged heater core or a heater control valve. Not sure where the valve is located ....waiting for the shop manual...

The blower is working however I don't get hot air blowing out the vents......The defrost seems to be working just fine...

Where is the heater control valve located.?

There is no heat blowing out the dash vents. Does this indicate a problem with the control vents/ blend door?

Any help would be appreciated.

 Thank you

[RubberCarrot]

Hi - I have the same car.  It too, put out no heat when I got it.  I replaced the blend door motor and it began putting out heat.  Although weak.

I also suspected a clogged heater core.  I did some work on it recently and took the opportunity to flush the entire system including the heater core.  I ran a garden hose through it in both directions and had good flow.  I tapped the garden hose into the heater hoses on the passenger side of the engine under the coolant reservoir.  So I think I would have been passing water through any control valve also.

I have not located a control valve.  Curious to see what turns up in this thread.

There is what seems to be, a restrictor in the upper hose.  That is where I tapped in on that hose.  It just has a smaller diameter opening it.  I assume its job is to keep water in the core for a bit to heat things up.  That restrictor has an arrow on it.  Out of curiosity, I have flipped it both ways, even though it didn't make a lot of sense.  No diff either way.

End result is no change.  But I have found that if I put the fan on low auto it gives the heater core time to collect a bit more heat before the blower blows it away.  After a while I put it back on full auto and 20 minutes into a drive it is comfortable.

I will say it is critical to burp that cooling system and to keep it full.  Make sure you have done that.  Burp it using that little valve on the thermostat housing.  You will also have better luck getting all the air out if you raise the front end.  I know, sounds lame but it makes a difference.  Ramps are good enough.  Don't let that little valve leak coolant without stuffing rags around it.  It will run right down to your distributor and that is not a place you want to be headed to next.  Been there, done that.  Rough job.

I am hoping this thread produces info on a control valve.  I have even heard there isn't one.

[Anthony C]

Thank you sir for that good information .....

 I have lots to do here......This is a really nice car .... so i need to do whats right to make it close to perfect. 

 I hope to post pictures and a complete DIY procedure. 

 Is the blend door motor easily accessible? and is a replacement available?  

[RubberCarrot]

If I remember correctly it is behind the glove box.  Not too bad to get to.  If I remember correctly, I took the glove box out to make it easier.  That was 7 years ago so...  I got it at Advance Auto.  It was in stock.  $134.00 if I remember right.

I just wobbled along with weak heat (it isn't my daily driver) until I tore it apart last October to replace the distributor, tune it up and take care of a slew of smaller issues.

The heat was better after I put it back together but still not what I would call "good".  I attribute that small improvement to burping the system while the front end was still in the air.  It is the only thing that was different after trying the heater core flush for the 1st time about a year before that.

[RubberCarrot]

If you ever head into the distributor look up this thread here.  1995 Fleetwood Brougham Light Throttle Stumble .

Way too much info there and I have not followed through with my promise to document it all.  There are a few dicey areas.  Save it for recreational reading.  LOL.  PM me if you do ever go there.  I can fill in some of that missing info for you.

[Anthony C]

Oh ....OK that dont sound too bad...

Im about ready to click the rock auto button .... Ill add one to the list.

 Yes Im doing the cap rotor and water pump as well ........I cant figure out why GM decided to put that distributor there...

 I Know my town car needed to be burped as well. Good tip raising up the front end BTW.

 Thank you so much for that info ...this is my first GM car so Im still learning...

 

[RubberCarrot]

When you have that distributor cap off check the shaft for lateral play.  Mine was shot.  But it didn't matter because I already planned to just replace everything.  I had no interest in having to go back in there.

If you need to pull the hub for the harmonic balancer save yourself some risk and use a puller that uses a pin that reaches into the crankshaft and bottoms out beyond the threads in the bolt hole.

I didn't have one of those so rented it from Advance Auto.  $128.00 for 45 days and you get 100% of that back.

That hub is really on there tight, probably because it is not keyed.  I actually went through 2 pullers because the threads gave out on the first one!  I was glad I didn't blow off the cautions I had heard and just used a bolt in the crankshaft to push against.  

If you do just replace the cap and rotor, you won't need to remove that hub.  Just the wheel part.

[Anthony C]

Ok .... I pulled the glove box ..... The blend door is working.

One less item to order....

 I dont suspect any major issues the car only has 60000mi Im sure the plug wire leads are degraded....so replacement is in order.

Great Info ...Thank You ..

[RubberCarrot]

60k miles?  That is really good! Mine has 135k.

Good luck with the project.  Let us know how it turns out.

[sonjaab]

Weak heat?  

I bet the heater core is clogged with the GM coolant sealer tabs.

I just went thru this last year when I got my 93 Deville.

I replaced the core and its clogged again!

Sure,  I could flush it but its 0 here in frozen NY so I will just suffer with it for the rest of  the winter

and either flush it or replace the heater core again!

Maybe your core is behind the glove box like my Deville but not sure.

I BET THAT THE problem since you checked your temp door acuator.

Your car prob. uses the same 3 way "tee" restrictor instead of a actual vac. controlled valve.

Edited February 2, 2020 by sonjaab

[sonjaab]

BTW:  Heat should NOT blow out the dash vents only when the a/c mode is selected will air

come out the dash vents.  Also depending on what temp is selected and warm a/c air will blow out the dash vents.

Heat/defrost mode air will only come out the defrost vent or floor.

Thats the way my Deville works so your Fleet should be the same.

[Anthony C]

Thanks SonJAab ... I did not know that ...... Im sure the door actuator is Ok now that you confirms how it works ...great info ...

 Thank You 

[sonjaab]

No prob.!

Another thing to mention is if that 3 way "tee" is installed in-correctly you will also have weak heat.

It seems one of the tee ends is restricted in some way to reduce the water flow.

Check to see if your tee is the original.  Look at the hose clamps.  prob. if they are the new

worm/screw clamps its been replaced.

Did u try to flush the core?

Sorry i dont have pics to post cuz i got a new laptop and they arent on it yet.

Check my old heater core post for pics of my Deville install.

Your Fleet may be similar!

 

[sonjaab]

Heres a link to my Deville heater core flush and pics of the  3 way "tee":

 

 

[RubberCarrot]

Well... I am reviving this old thread in the hopes someone can give a new idea.

I have no heat.  None.  Weak heat has always been an issue and I have tried all sorts of things as seen above.

Quick recap:

Blower works fine.

Heater core flows water from a garden hose unimpeded, in both directions. (tapping into the heater core hoses along the passenger side of the engine)

Two heater hoses.  Upper one is the return and gets barely warm.  Lower one is the feed to the heater core and gets too hot to hang onto.

Blend door motor has been replaced (years ago)

I figured it has to be clogged plumbing in the return hose, between where I tapped in to flush the heater core, and the water pump.

All the plumbing along this stretch is original, with original clamps and the steel retainers riveted onto their corresponding brackets.  Never been apart from what Ican tell.

All plumbing is pliable and appears to be in good shape.  Looks like new.

Today I pulled that return hose off the water pump.  

I was able to feed 27 inches of zip tie into the hose.  I felt no clog or obstruction along the way except for the 90 degree bend by the alternator.  That 27 inches of zip tie reached through and past the 3 way T where the return connects into the coolant reservoir.  That is where I tap in to flush the core so I know it is all clear beyond that point. 

I also was able to push a good 8 or 9 inches of zip tie into the water pump with no obstructions.

I am at a loo as to why there is no coolant flow through the heater core.

If anyone has any suggestions, please speak up.  If not, I think I may put it back together with the hoses reversed at the water pump and see what happens...

Thanks in advance!

[rockfangd]

I just went through this on a 90 Silverado last week. Hose was hot coming in, hose going out was cold. Core was plugged on the inlet side. Back flushing resolved this

A few thoughts. IIRC the supply comes in on the top of the core. 

The return is on the bottom and returns in your case to the top of the water pump.

I always had air issues with these and purchased a coolant funnel  that raises the highest level of coolant which helps to push the air out. Another tip is to raise the front end of the vehicle to raise the height of the highest point. 

With the coolant funnel hooked up and car running I keep squeezing the hoses until all air is expelled out of the funnel. 

If you remove the return hose from the water pump and the hose that goes to the core, flush it through and it flows well, then there should not be a blockage

 

[Göran W]

I have never opened a core so just my 5 cents..... Can there be a "shortcut" inside the core and the rest is clogged?

[sonjaab]

Does your TEMP door move or function?

If its not moving all the way could cause poor heat.

As far as tearing open old core:

I pulled my core and took the ends off.

Plenty of the GM sealant threads piled up.

New core and still weak heat.

Installed new 190 thermostat and BANG !

Heat roast you out of car.

I figure being from Fla. maybe it was swapped to a 160 to run cooler

or reduce dash heat for better a/c performance.

I HAVE posted a thread around here............

[rockfangd]

 the OP states a very different temp feel between the 2 hoses to the heater core. Thermostat is not a bad thought either. Have been waiting for the OP to respond to know where to proceed

[cdgrinci]

Don't put a 160 degree thermostat in your car as it will prevent going into closed loop.  Your engine will run rich and fuel mileage will suffer because of it.