very little heat front/rear
- Thread starter braddaddy
- Start date
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stamp11127
Full Access Members
Before throwing more parts at it do this simple test.
1) Warm up the engine to normal operating temp
2) Feel how hot both heater hoses are under the hood
If they are both cold there isn't flow through the core. If one is hot and the other colder the core may be plugged or the restriction valve is blocked.
Is there rust in the cooling system?
Also burp your cooling system to remove air pockets.
What ratio was used with the coolant? This isn't the problem but never hurts to know. Tap water, distilled or premix?
Those clips holding the heater hoses on have always been a ***** for me - even with the tool to release them. If you think the cores are clogged an "easy" test is to remove the heater hoses and run water through the core. Logically if the front core is plugged so is the rear one. Dorman makes replacement connectors to make up a water feed line.
How many miles on the engine? Other than throwing parts at it, has any maintenance been done on the cooling system in the past? Has any stop leak type of product been dumped in?
1) Warm up the engine to normal operating temp
2) Feel how hot both heater hoses are under the hood
If they are both cold there isn't flow through the core. If one is hot and the other colder the core may be plugged or the restriction valve is blocked.
Is there rust in the cooling system?
Also burp your cooling system to remove air pockets.
What ratio was used with the coolant? This isn't the problem but never hurts to know. Tap water, distilled or premix?
Those clips holding the heater hoses on have always been a ***** for me - even with the tool to release them. If you think the cores are clogged an "easy" test is to remove the heater hoses and run water through the core. Logically if the front core is plugged so is the rear one. Dorman makes replacement connectors to make up a water feed line.
How many miles on the engine? Other than throwing parts at it, has any maintenance been done on the cooling system in the past? Has any stop leak type of product been dumped in?
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bigfry
Member
Not to highjack the thread, but this is exactly what I came on here tonight looking for myself. Thanks for the tips so far.
I bought the '02 used so I dont know about previous radiator repairs or additives....
180K miles....
Warmer today and my upper hose and 2 core hoses are hotter than on colder days....I couldnt hold them for long bare handed. Also the hoses seemed to have higher pressure inside inside.
these hoses are always the same temp in relation to each other.....just cooler when its colder outside and hotter when its warmer outside.....which of-course allows my heat to be warmer when its warm out and cooler when its cold out
I had 2 different shops look at it and of course they say what they find is ok...but I had it in the shops in late spring when the heat "felt" normal due to it being warm outside.
They both did rad flush and replaced tstat and said they flushed core and checked water pump.
Its directly related to the outside temp....the colder it gets outside the less heat I have inside.
180K miles....
Warmer today and my upper hose and 2 core hoses are hotter than on colder days....I couldnt hold them for long bare handed. Also the hoses seemed to have higher pressure inside inside.
these hoses are always the same temp in relation to each other.....just cooler when its colder outside and hotter when its warmer outside.....which of-course allows my heat to be warmer when its warm out and cooler when its cold out
I had 2 different shops look at it and of course they say what they find is ok...but I had it in the shops in late spring when the heat "felt" normal due to it being warm outside.
They both did rad flush and replaced tstat and said they flushed core and checked water pump.
Its directly related to the outside temp....the colder it gets outside the less heat I have inside.
stamp11127
Full Access Members
Since both hoses are "too hot to handle" then the core probably isn't clogged. I would move on to a flow test of the feed and return ports on the engine. With the heater hoses disconnected you will be able to see if there is a buildup of junk inside the hose.
What temp tstats have they been using? When changing the tstat are you placing the little hole in it towards the fan side? When I changed my water pump & rad, I parked on an incline with the radiator being the highest point. Then bled the usual way.
Once the engine is warmed up the heater hoses shouldn't change temp in relation to the outside temp. This could indicate a flow problem.
What temp tstats have they been using? When changing the tstat are you placing the little hole in it towards the fan side? When I changed my water pump & rad, I parked on an incline with the radiator being the highest point. Then bled the usual way.
Once the engine is warmed up the heater hoses shouldn't change temp in relation to the outside temp. This could indicate a flow problem.
Yes Im thinking low flow /blockage also....
Yesterday after driving the Expy I turned it off and started looking for the fan motor resistor and I could hear gurgling coming from the heater core area under the passenger side dash.... And thats right away after turning off ignition, getting out and walking over to passenger side, opening door, turning on phone flashlight and sticking my head under the dash.
Yesterday after driving the Expy I turned it off and started looking for the fan motor resistor and I could hear gurgling coming from the heater core area under the passenger side dash.... And thats right away after turning off ignition, getting out and walking over to passenger side, opening door, turning on phone flashlight and sticking my head under the dash.
mjlcobra
Active Member
I joined this forum after lurking for the past year specifically to reply to this post. I also had NO heat or defrost for over a year. I bought the truck in July of 2012 and found out the hard way I had no heat (around November). I did hours and hours of research to decide that surely my heater core was bad. I ran water via a garden hose through the core in/outlets followed by compressed air. I noticed that "not much" water was going in before it began to come out. I determined that my core must be severely plugged. I roughed it out through the Indiana winter determined to change the core when it warmed up. I waited until last month and finally tackled it! There's a nice youtube video that covers about 85% of the job. Man was I excited once it was all back together with only 2 extra screws (out of probably 80 or so - I'll take it)... Well, I still didn't have heat. I did everything as directed to bleed the system properly. Hmmm well I ran a flush and that didn't fix it, so I know I didn't have huge deposits in there. I pulled the inlet hose off and started the truck. Nothing. I determined that my water pump must be bad. Mind you, I had NO coolant leaks OR overheating. I wish I had saved the picture, but the fins on my old pump WERE INEXISTENT, and the impeller was literally as thick as maybe... 3 sheets of notebook paper. Changed the water pump and once burped free of air I have awesome heat. Not to mention, my passenger side head gasket leak DISAPPEARED. I have a 4.6 Windsor and had planned on doing the head gaskets but decided it wasn't worth the money for the. $4000 I bought the truck for (109,500 mi - 120,000 now). It's been a month since doing this, the oil was changed and has the full six quarts. I've not lost a drop on my garage floor and the familiar burning smell / smoke cloud is GONE. I know this post was cumbersome, but if wanted to achieve a lot of information on one shot. I hope this helps at least one person because I found exactly zero people with this experience online! Good luck and PM me or email me with questions (anyone).
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stamp11127
Full Access Members
And that is why we flow test not only the core but the supply to it.
mjlcobra
Active Member
I agree with ya, stamp. This was definitely a learning experience, which is why I wanted to share my story. I never thought to test the flow until the new core didn't fix it. I had my mind made up that my core was blocked. The HG oil leak was not there when I bought the truck. I incorrectly assumed that the car lot I bought it from put a stop leak as a band aid to hide the leak and sell the car. I had no leak until my 3rd week owning the truck. I also theorized that the previous owner was informed of the "head gasket oil leak" and only heard "head gasket leak" and dropped a bottle of bars leaks or something similar to the cooling system and it settled in the core. I mean, with theories like this and self-convincing... I made myself believe it! I had no idea that a water pump could properly cool the engine and still have insufficient flow! Again, I truly hope my experiences save someone else's precious time. Unfortunately as a weekend warrior, I am forced to follow my gut or the oh-so-wrong concept of throwing parts at it.
IMINYOURCHAIR
Full Access Members
the quick connects on the heater core lines. I would and did replace mine with the screw clamps. they are much easier to remove and they do not leak. Good to see you all fixed it. but I do agree that it's a good idea to first check that the water pump is indeed pumping before going to the measure of removing the dash.
