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Topic Review (Newest First)
01-10-2014 10:14 PM
WBN3 Glad it worked for you. Much easier than replacing the water pump.n
01-10-2014 05:41 PM
Bigmarge22 That was the trick. The heat works great.
01-07-2014 10:56 PM
Bigmarge22 Thanks for bumping this thread. I found out tonight that my heat doesn't work very well. It looks like I will start with a heater core flush this weekend once it warms up. We're not used to this freezing crap in GA.
01-07-2014 10:12 PM
WBN3 Just re-read and bumping this thread... given the "polar vortex" it may be worthwhile for some of you guys north of the Gulf Coast...
04-06-2013 11:00 AM
Scl This is exactly how my pump on my 1999 looked. $30 for a new one, not rebuilt, at NAPA.
01-30-2013 11:34 AM
erickpl
Quote:
Originally Posted by jeepsrgreat View Post
Well...put it all together and did a complete system flush. Thought why keep flushing the heater core and have the rest of the junk in the system plugging off the core. Found that the pump was not as good as I thought. After flushing the pump seal was shot. Must have been enough junk in it to keep it from leaking. Off the the parts shop in the morning for a new pump. Hope it works....forecast is for -35C for Tuesday.
Exactly what happened with mine. Glad it is working for you.
01-30-2013 08:06 AM
jeepsrgreat Minus 31C last night and minus 18C this morning and jeep is warm ...life is getting better!
01-27-2013 11:06 PM
jeepsrgreat New pump is in....no leaks...now to see if I have heat. Won't know till Tuesday night.
01-26-2013 11:12 PM
jeepsrgreat Well...put it all together and did a complete system flush. Thought why keep flushing the heater core and have the rest of the junk in the system plugging off the core. Found that the pump was not as good as I thought. After flushing the pump seal was shot. Must have been enough junk in it to keep it from leaking. Off the the parts shop in the morning for a new pump. Hope it works....forecast is for -35C for Tuesday.
01-26-2013 01:09 PM
jeepsrgreat Picked up flushing chemical. New thermostat. New cap. Going to put it all together and see what happens.
01-26-2013 08:06 AM
ohioviper Take heater core hoses off where they mount to the engine and hook up a garden hose and flush it both ways for a long time and then do it again.Ive flushed sons 2000 3 times now and Im still getting junk out of it.
01-26-2013 12:53 AM
jeepsrgreat Pulled the pump today....it looks like new inside. Going to put it back together tomorrow. Going to flush the core again while it's apart. I will get heat....I will win....thinking positive.
01-23-2013 09:47 PM
jeepsrgreat Waiting for a warmer day

Attachment 201264



Attachment 201265
01-20-2013 08:42 PM
ohioviper Changing the water pump is an easy job.If you have a lot of miles just go ahead and do it right if you have the money .Change water pump ,thermostat ,all hoses and serpentine belt and idler and tension-er and the fan clutch.If your radiator is questionable now is also the time to replace it.
01-20-2013 05:47 PM
jeepsrgreat I'll try this when I get a chance....I kinda hope these is no flow so the problem is solved.
01-20-2013 03:22 PM
Whitfimb
Quote:
Originally Posted by WBN3 View Post
Spent four hours on it this evening, to no avail:

- disconnected the supply hose to the heater core, cranked engine and watched to see if water came out the t-stat housing; it did NOT flow out, even though I had previously pushed water out that opening by flushing with a garden hose into the supply side, through the core back to the block and out the top; this maked me suspect either the water pump is wonky or there is some sort of anomaly inside the t-stat housing

- !

Looks like he just looked for flow out of the t-stat housing. I like the evevated hose because it requires a pump in good health to pass the test.
01-20-2013 03:15 PM
Whitfimb You can do what the op did. Drain and refill with water, then remove the heater hose from the water pump plug it (heater core side) Install another hose, Hold the hose up high - 18" above the radiator or so. Fire the jeep up. See what kind of flow you get. It should flow like a water hose. Only ru it quick as you should be pumping cooling water out of the open hose. The op got no flow out of the eleviated heater hose. The bad impeller would not overcome the head pressure (weight of the water in the evelated hose). I need to do the same test.
01-20-2013 11:34 AM
jeepsrgreat I've have the low heat problem as well. I have done the flush. Checked the blend door. Heat blows warm, but never hot. At around minus 15C I have just about lost all heat, and yet I see others driving with soft tops. I have flushed and checked enough that I have given up on the problem and wear gloves and a toque. After seeing this, I'm thinking it may be my pump. Does any one know if there is a test I can do before I pull it? A pressure test of some sort? Not sure if it matters, I have a '98 4L with no ac. I have heard jeep heaters are directly linked to the bowels of hell, all I have is a warm summer breeze.
01-20-2013 06:32 AM
Whitfimb When I was wrenching for a living the Jeep water pump with no impeller was seen on occasion. We attributed it to the new environmental friendly style coolant that turns acidic and and attacks the impeller metal.

Importance of the pH Value in Engine's Coolant / eutechinst.com

From the time the coolant is introduced into any type of engine it starts a gradual degradation process into corrosive acids. This degradation is a function of time, temperature and the types of metals used in the engine and components construction. Once the coolant turns acidic all engine metals start to dissolve. The results are leaking water pumps, heater cores and radiators.

With the increasing number of aluminum engines and components the corrosive process is accelerated since the coolant degrades much faster in contact with aluminum than in typical cast iron engines. During the preventive maintenance of any engine, in addition to the freezing point, the pH value of the cooling system should be checked.
12-13-2012 02:08 PM
erickpl
Quote:
Originally Posted by brad98tj View Post
Was your jeep still running at the right temp. I have the heat problem too and think it could be the pump.
It ran cool if anything (at least indicated on the temp indicator). Water just wouldn't circulate very well at all obviously. It never overheated though.
12-13-2012 11:58 AM
IslandTJ I would supplement the heater core flushing process by adding a step of having a solvent sit in the core for a while and then flushing and backflushing. From what I've researched, the safe solvents for the core are a mixture or heated water and vinegar or a heated critic acid solution.

I've read that some people have used CLR with success but I think it is too strong and may cause damage. Others have used radiator flush or "minute" flush but I haven't seen any positive effective reviews of these types of solvents.
12-13-2012 10:06 AM
brad98tj
Quote:
Originally Posted by erickpl
Water pump.

I had the exact same issue. No heat, hoses not getting hot. Replaced t-stat. Same thing.

When I did a flush and reverse flush, I got gunk out of the core and thought I was good. When I tried to test it, I had Niagara Falls coming out of the pump. By the time I got the pump off (easy to do btw), I noticed the damned thing would barely spin. A few bucks later I'm installing a new one. If you go this route, note on the impeller if there is an "R" imprinted. This denotes reverse flow (which my 97 2.5L used). Things run a LOT smoother and my heater core warms up QUICKLY now (less than 5 minutes or so, depending on ambient temps).
Was your jeep still running at the right temp. I have the heat problem too and think it could be the pump.
12-08-2012 11:20 AM
Jerry Bransford
Quote:
Originally Posted by CaseInternational View Post
Did changing the water pump fix the no heat in the cab problem? My Jeep does the same thing and I am reasearching what options to look at for fixing it.

Jeff
Lack of heat from the heater is usually caused by a clogged heater core that can be fixed by flushing it back & forth with a garden hose.
12-08-2012 08:09 AM
CaseInternational
Quote:
Originally Posted by WBN3 View Post
Update (if anyone is interested):

Finally got around to changing the water pump, and this is what I found:



Really surprised it wasn't overheating, although with the t-stat sitting right on top of the pump housing, I suppose it could move enough water to keep it (the temperature sensor) cool. The real question is what kind of damage may have been done in the engine itself where small passages like the heater core weren't allowing much flow. Anyone out there seen this before?

Did changing the water pump fix the no heat in the cab problem? My Jeep does the same thing and I am reasearching what options to look at for fixing it.

Jeff
12-07-2012 10:16 PM
scott howard after seeing that i will be replacing mine just to know i have a new one.
Jeeps are amazing in their ability to run even thru a life of abuse.
06-11-2011 09:57 AM
jayb Mine liked like that when I replaced it. Amazing that the jeep was still running at all, but mine never even overheated. I flushed heater core, and around block, and radiator. Replaced all hoses,heater included.
You'll be fine.
06-11-2011 01:15 AM
WBN3
Smoking gun?

Update (if anyone is interested):

Finally got around to changing the water pump, and this is what I found:



Really surprised it wasn't overheating, although with the t-stat sitting right on top of the pump housing, I suppose it could move enough water to keep it (the temperature sensor) cool. The real question is what kind of damage may have been done in the engine itself where small passages like the heater core weren't allowing much flow. Anyone out there seen this before?
04-20-2011 02:34 PM
99Wrangler4x4
Quote:
Originally Posted by WBN3 View Post
Well, that's nice... it's black just like mine. Too bad you've got the 4-cyl., guess that's better than not having a jeep... have you had this problem, or are you just trolling...
I tried to help ya but I've never had this problem. Just thought I'd share
04-20-2011 12:55 PM
WBN3
Quote:
Originally Posted by randy and teri View Post
its easier to set the thermostat into the recess and then put the housing down around it rather than try to keep the thermostat in the housing defying gravity.
....
i would just replace the pump, mainly since the amount of time spent redoing the same little things is probably more time than it would have taken to do the water pump
the upside is once its done, you know what you have and that its correct and clean.
Yes, I set the t-stat into the recess, but the bottom bolt on the housing was difficult to get lined up with its hole on the block, so I think I bumped the thermostat when I was trying to get it aligned. Used a smidge of white lithium grease to hold it to the block long enough to position the housing the second time around. As for replacing the pump, that's apparent to me now, but I am cheap and didn't want to do it unless I had to...
04-20-2011 12:51 PM
WBN3
Quote:
Originally Posted by 99Wrangler4x4 View Post
Hey! I have a 99 TJ!
Well, that's nice... it's black just like mine. Too bad you've got the 4-cyl., guess that's better than not having a jeep... have you had this problem, or are you just trolling...
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