Additional coolant heater

[MarkEagleUSA]

The exhaust brake is my favorite add-on for my truck.

Sadly no exhaust brake on my 03 auto.

 

[MarkEagleUSA]

or a blend door doesnt work correctly.
only 5-8° difference inlet to outlet is way to less and shows a bad heat tranfer either from the core or the blend door.

This has me confused. Are you saying that 5-8° difference is too much? Also, how does the blend door affect the in/out temps if the blower isn't on and there's no air flow across the core?

Plans got changed for tomorrow so weather permitting I'm going to try and get the core flushed.

 

[RBridenbaugh]

They're not just for manual transmissions

PACBRAKE'S DIRECTMOUNT 4'' PRXB EXHAUST BRAKE KIT #C44049

Application: 2003 - 2004 Dodge RAM Cummins 5.9L ISB 24 Valve Engine with 47RE / 48RE Automatic Transmission.

 

[MarkEagleUSA]

They're not just for manual transmissions

PACBRAKE'S DIRECTMOUNT 4'' PRXB EXHAUST BRAKE KIT #C44049

Application: 2003 - 2004 Dodge RAM Cummins 5.9L ISB 24 Valve Engine with 47RE / 48RE Automatic Transmission.

That's a pretty expensive option for providing more heat!

 

[The patriot]

I got my dad a quilted winter front for his 1st gen in the early 90's.
He harted it (ugly AF) and almost returned it,,,but once installed he LOVED it.
They were in upper NY state at the time and -40 was guaranteed a few times a winter.
I feel for ya. My 1998 was never a good heater. More than once I saw 0 or a little colder and ran the heat on high for the entire 50 mile trip, and STILL was cold in the cab.
It regularly takes me 4-5 miles before I can feel a little heat in the really cold weather.

 

[cerberusiam]

This has me confused. Are you saying that 5-8° difference is too much? Also, how does the blend door affect the in/out temps if the blower isn't on and there's no air flow across the core?

The higher the difference the more heat is being pulled form the core and into the air. The 10-12 with blower on high is better but still think that may be short of what is needed. If the blend door is not opening all the way it cuts the air flow over the heater core and you get less heat into the cab system. It could be the core is corroded inside and not transferring heat or the blend door not allowing flow.

All things functioning correctly you can sit in shirt sleeves in -20 weather with no issues, when something interferes you are lucky to keep the ice off the inside of the window.

 

[MarkEagleUSA]

All things functioning correctly you can sit in shirt sleeves in -20 weather with no issues, when something interferes you are lucky to keep the ice off the inside of the window.

Once she warms up I do get blown out of the cab. It's the warm up period that bothers me.

I know the recirc door is bad. Mode and blend seem to work properly. I'm hoping to do the door upgrade but that has to wait until next spring/summer... in the middle of a kitchen remodel that's taking forever. It has severely limited play time with the Ram.

 

[MarkEagleUSA]

Still haven't had a chance to flush the core (had to replace the exhaust yesterday) but I did put some cardboard in front of the radiator (between the intercooler and radiator) to see if it would help. This morning it's about 38° and she warmed about just past the halfway point, so maybe 2-3 miles/5 minutes earlier. According to tracking my winter cover should be delivered today. Hoping that makes more of a difference.

 

[MarkEagleUSA]

Winter cover arrived yesterday and I installed it last night. I was surprised at how much it really covers... they don't want any air getting in there, do they?

This morning it was 29°. Light frost on the windows required the defroster from the get-go. Defroster air seemed warm enough to do the job. Engine temp came up by about the halfway point of the trip in which I guess is better than the 3/4 point. I need to find time this weekend to get the heater core flushed. Even if it's not clogged it can't hurt to clean it up and make sure the flow is ok.

 

[JR]

You'll be surprised how much heat is retained inside the engine compartment with the front on and block heater plugged in.

 

[MarkEagleUSA]

Had time to try and flush the heater core yesterday after work. Opened the hood to start and noticed the heater hoses didn't look too good. Didn't want to remove them and have something go wrong so I ordered a pair from Amazon. One will be here tomorrow and the other on Sunday (gotta love Amazon Prime) so maybe I can get to it Sunday afternoon.

 

[DonFitzwater]

FYI- for fast heat, I use either an Espar or Webasto heater. They are nice because in warm temps like you are experiencing, you only need to run them about 20 minutes and you have heat as soon as you drive off. If it happens to get really cold, you can run them for supplemental heat while driving. Most folks never need this unless they live far north.

 

[MarkEagleUSA]

Finally got my new heater hoses and clamps. On Wednesday night after work I popped the hoses off (without incident) and flushed the core. Nothing of note came out so I don't think it was blocked at all.

Now I'm thinking the upper blend door is broken which would cause it to stay closed on top of the heater core. If I go to full defrost, I get very cold air due to the fact that the a/c compressor turns on in that mode. Hopefully tomorrow I can pull the glove box and remove the lower dash to verify.

My plan for now is to try and get the door open and drill a small hole in the HVAC case to pin it up until I can get a set of replacement doors and pull the box to fix it right (which will likely have to wait until the spring).

What are the opinions on replacing the 5 doors in the box? Are current OEM doors upgraded , or do they still have the same flaws as those that came on the truck? I know there's the aftermarket Heater Treater and Blend Door USA doors, and I also see that Dorman sells replacements that appear to be the same as OEM (at least in the pictures I've seen on the web). Is there any consensus on which replacements to use?

 

[DonFitzwater]

I’ve done three of the third gen dash upgrades and all with Heater Treater. AFAIK, they are the only ones making them out of all metal. I’ve had no failures after repair. If you are going to pull the HVAC box and replace doors, do the heater core and evaporator core as well.

 

[MarkEagleUSA]

all with Heater Treater. AFAIK, they are the only ones making them out of all metal.

The HT doors are all metal and BDUSA are aluminum. Not sure if one's better than the other, but the HT set is less expensive.

do the heater core and evaporator core as well

Definitely. Not going to skimp if I'm doing all that work.
It will be a pricey fix but worth it in the long run.

 

[MarkEagleUSA]

Now I'm thinking the upper blend door is broken which would cause it to stay closed on top of the heater core.

The saga continues. Went out this morning and pulled the glove box and lower dash to check the blend doors. They're fine! Or at least they're working properly, as were the mode doors.. I knew the recirc door was bad and had bought a Dorman replacement a while back so I put that in by removing the blower motor. It helped but didn't solve the problem.

So after sitting there for several minutes muttering to myself I decided to pull the heater hoses and flush the core again. As I flushed it, I noticed the water would run cloudy for a few seconds before turning clear. This happened both ways. When I did this the other day it was dark and I guess I didn't notice the cloudy water. I alternated between the 2 hoses and let the water run for several minutes each way about 5 times each. By last flush the water was running clear from the get go. I let everything sit for about 30 minutes and then flushed them again. Twice the cloudiness was there but much less than before. The 3rd flush ran clear.

Reconnected the hoses, topped off the radiator, and let the truck idle while I connected the heater control (didn't put any of the dash back). Took the truck for a ride and within minutes she was throwing heat like the sun! Maybe when I flushed a few days ago I loosened some stuff up and today finally worked it free. My plan is to go out in the morning and take her for a ride to see what happens. While it's only supposed to go into the mid-40's tonight, I should be able to tell if there's a difference. Keeping my fingers crossed.

One thing I noticed since putting on the winter cover last week is that the ambient temp sensor is located behind it. The overhead console was reading 65° today when it was only around 40°. So I removed it from the radiator support and placed it in a hole by the headlight housing. When I took my second test drive it seemed to read properly. What's weird is that the service manual says the sensor should be up on the hood near the firewall but mine was right on the driver side radiator support.