Poor heat, bad heat, crappy heat

[bam]

Warning, super rambling.

So I've been plagued with this through 3 different Escort Gt's and a BP Tracer. Even with half the radiator blocked off (FWD BP's are cold runnning whores.) I tried flushing the heater cores and running that flushing agent you can get at auto parts stores, all to no avail. I never seem to hear about others with this problem but know someone else has to have had the issue. I think I finally found a solution.

Basically there is a clog and flushing agents and flushing just the heater core won't get it. The clog is in the sandwich oil cooler on the block. The coolant to the heater core goes through the oil cooler first. If there is a clog in the cooler it doesn't matter how clean the rest of the, heater core/ block/ radiator/ lines are.

I wound up going to the hardware strore and buying a 5/8inch male barbed fitting/female garden hose end. It was $4. This plugs right into the heater hoses and with a clamp will only blow off if there is a major clog(which mine had.)
I just took off the intake, then took off the two heater core hoses right on the side of the head over the trans. Aimed one at the ground and one plugged into the garden hose. Flush one way then the other. After I blew the hose off in my engine bay I had to work up the pressure untill the clog was gone. It took a solid 2 minutes of full garden hose pressure untill the cooler ran clean.

My heat rocked immediatly. I flushed the whole system 4 times for good measure. Hopefully I and someone else won't have such a miserable winter.

[jay]

Hmm. I think I'll try this out!

[Turpro]

Not a bad find. Mine works fine id its above 20 out but below that it sux. Might have to try this out

[Cool_Steve]

My mom's Protege has had failing heat since 2008. It only manages to get luke warm, mine still gets super hot. I always thought her heater core got screwed up because she didn't change her coolant as much as I did and her old coolant destroyed the core (can this happen?). I even got someone to blast the core but it still didn't work. She doesn't want to spend the money/have the dash ripped apart. Pictures would help this thread, as I'm not as mechanically inclined as others here and would someday like to try this.

[gofanu]

My 94 DX B8 heats like a fart in a hurricane. Had a new rad, WP etc when I got it, nearly froze to death bringing it home from Alabama once the temps got down to 35F. I have flushed and blown out everything including all the pipes and hoses, heater core runs clean and fast, but NO HEAT! If I leave it running with everything on high, it will eventually melt the ice off the glass, but as soon as you move you froze. All the doors and flaps are adjusted correctly, near as I can tell without taking it all apart. No sandwich cooler on B8.
Only thing I can figure is that somewhere in the mass of mostly invisible crossover pipes behind the engine the PO hooked up something wrong. Is there a diagram of how these should be?

FRM

[bcowie]

I changed my heater core to the Escort one that is twice as thick even at 20F I can take off my jacket in the car.

[bam]

Page down a few posts....http://forum.miata.net/vb/showthread.php?t=367790
The only other place I could see a clog is the return pipe that runs in front off the block to the water pump inlet.

I should add your heat will still suck if the engine itself isn't getting up to temp. I run an auto radiator, which is over half way blocked off with part of a vinyl sign. I block off enough to make sure the temp guage doesn't cycle during cruising. Or only a tiny bit, big swings are bad for the stat and engine itself. When I did the thermostat a couple years ago I made damn sure to get an oem style dual stage thermostat. The main opening is smaller than a stant or store brand.

I had a BP chuck a water pump belt once, the car toook 5-10 minutes to get too hot and would cool off after 5-10. You can drive these things air cooled its ridiculous.

Honestly, I think the thicker escort heater cores don't do jack but make it harder for the blower motor to blow through.

P.S. Until I flushed the crap out of the cooler my heat would be luke warm to about 20F, colder than that would be miserable.

[bcowie]

Page down a few posts....http://forum.miata.net/vb/showthread.php?t=367790
The only other place I could see a clog is the return pipe that runs in front off the block to the water pump inlet.

I should add your heat will still suck if the engine itself isn't getting up to temp. I run an auto radiator, which is over half way blocked off with part of a vinyl sign. I block off enough to make sure the temp guage doesn't cycle during cruising. Or only a tiny bit, big swings are bad for the stat and engine itself. When I did the thermostat a couple years ago I made damn sure to get an oem style dual stage thermostat. The main opening is smaller than a stant or store brand.

I had a BP chuck a water pump belt once, the car toook 5-10 minutes to get too hot and would cool off after 5-10. You can drive these things air cooled its ridiculous.

Honestly, I think the thicker escort heater cores don't do jack but make it harder for the blower motor to blow through.

P.S. Until I flushed the crap out of the cooler my heat would be luke warm to about 20F, colder than that would be miserable.

I disagree when its -20 outside the factory heater core just doesn't have enough surface area to heat up the air enough, luke warm just doesn't cut it, I couldn't even defog the windshield before.

[Raider9864]

I see A LOT of Chevy Blazers with this same issue. 2 minutes with a garden hose and the heat is as hot as a summer day in Arizona (i guess i dont live there). It's the first thing I do whenever a GM product comes in with no heat. That damn Dexcool is garbage! Maybe its time to do a complete freeze flush if its getting clogged up like that....

[Cool_Steve]

I want to add something I discovered with my mom's car and its lack of heat.

Blowing full speed on vent on the cold setting I get decent airflow through the vents closest to the clock and the ones by the doors. However blowing full speed on vent on the hottest setting there is little airflow through the vents closest to the clock and pretty much nothing by the ones near the doors. Is this a common issue?

[CaymenEGT91]

Ive hardly ever had BGs give me heating issues, mine was for a while but the Tstat was stuck open, and Kris's car has **** for heat but its because of his 2" Core Aluminum Radiator! lol

[bam]

"I want to add something I discovered with my mom's car and its lack of heat.

Blowing full speed on vent on the cold setting I get decent airflow through the vents closest to the clock and the ones by the doors. However blowing full speed on vent on the hottest setting there is little airflow through the vents closest to the clock and pretty much nothing by the ones near the doors. Is this a common issue? "


If you're getting poor air flow on the heat setting you have either leaves and garbage in the cowl area under all the plastic under-neath the wipers, on the passenger side. And/or a bunch of crap stuck on the heater core itself inside the black plastic heater core/evap box under the dash.
All my BG cars have had a ton of crap under the cowl. I never bothered opening up the actuall heater boxes. "Its stuck in there with glue or something I don't know" but I know there's a pic floating around with leaves and evergreen twigs, stuck on the heater core.
On a simpler note, crank the fan up.

[Cool_Steve]

^I will have to check the wiper area. The fan was cranked on high 4, and on cranked heat the air-flow and temperature coming from the vents and lame. If the heater core is working properly both hoses going to it near the firewall should be warm when the car is running, correct?

[bam]

I want to say yeah, but on my car with the super clogged oil cooler, both hoses were hot all the time and the heat still sucked. The coolant in the hoses got hot it just didn't circulate.

[Cool_Steve]

I want to say yeah, but on my car with the super clogged oil cooler, both hoses were hot all the time and the heat still sucked. The coolant in the hoses got hot it just didn't circulate.

-My mom's Pro is the 1.8L SOHC...does that have an oil cooler?
-Checked interior linkages - everything works like it should.
-Didn't want to take everything off to see under the wiper area so I stuck my camera in there. Only a leaf or two, nothing else. So the issue isn't blocked airflow.
-I should note that even when she bought her car years ago...my fan settings in my Pro have always been a bit stronger. Like a "3" setting on her's would be a "2" on mine.
-Ran the car for a while in -12C weather, heat and fan cranked on defog. Left heater core hose gets hot. The right one...nothing more than room temperature, which is exactly the temperature of air that gets into her cabin when it is this cold. The heater core must be toast, correct?