KJ question.....no heat (fixed), now headlight questions

[mjeff87]

Every fall, I have to flush my heater core in the KJ to remove an air pocket so I get full heat for the winter.  It's worked every time.....until now.  I just had the radiator replaced and had a new thermostat installed last month, and the shop swore up and down they bled all the air out of the system.  Not.

 

I've flushed the heater core 2X now, ran it without the cap on the tank until the t-stat opened.  Squeezed both upper and lower rad hoses endlessly, and even managed to get the bleed screw on the water neck unscrewed and purged every bit of air out.  (side note, I don't think that screw has ever been unscrewed since new.....).  I've got a definate temp delta between both core hoses (about 155 in, 100 out), so I know the core isn't clogged but I can't get cabin air above about 125 degrees.  The blend door is functioning correctly also.  There's still an air pocket inside the core that I can't push out.

 

Any tips or tricks I don't know about?

Edited November 7, 2018 by mjeff87
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[Pete M]

mouse house inside clogging the airflow? 

[mjeff87]

LOL, I don't think so.  I've got good airflow out the vents/defrost.

 

When I was flushing it, especially in reverse, I got a big slug of air out repeatedly.  I just can't seem to get it out and keep it out long enough to hook the hoses back up.  Core is a stupid design, it has both inlet and outlet at the top.

 

I'll try flushing it one more time.  I might buy some spare hoses and try to fill the core up after flushing by holding the hose ends up high and pouring coolant into them, then quickly try to pull them off and put the engine hoses back on.

[Pete M]

I guess it's also possible that the heater core has finally plugged itself up inside (especially on the bottom away from the in and out)

[mjeff87]

It's possible, but I'm not convinced of that.  I've been religious about cooling system maintenance on this thing since I've owned it, considering its one of the Achilles heels of this engine (along with dropping valve seats.....)

 

My driveway slopes toward my garage slightly, so I think I'm gonna try flushing the core again this weekend with the nose pointing in the other direction to see if it makes any difference.  I'm hesitant to put any kind of flush chemical into the core (I have CLR on hand) for fear of developing a leak in the damn thing.

 

The heat output is marginal, which is ok for me here in VA.  But, I have to roadtrip this thing up to PA in January and I'll definitely need some better output for that, lol.

[Manche757]

MJ

On 10/29/2018 at 8:31 AM, mjeff87 said:

 

I've got a definate temp delta between both core hoses (about 155 in, 100 out), so I know the core isn't clogged but I can't get cabin air above about 125 degrees.   .

 

 

I have only luke warm heat on an 89 MJ.  I am on coastal VA and it does not bother me that there is  little heat. The dashboard temp gauge only reads about 120 to 125 when warmed up. I assume either the gauge is stuck open or a prior owner removed it altogether.  mjpete, when warmed up, what temperature does your gauge show?  Is it inline with the 155 you get coming off the engine?   30 year old gauges and sensors.

 

For anyone, what were the original stock thermostat ratings and what are several of you running if not the factory spec one?

[mjeff87]

I got it

 

i went medevil on the core.  Pulled the expansion tank and core hoses like I normally do, but forward and reversed flushed it for about 20 minutes.  Then I blew the core out with air and filled it with a mix of white vinegar and boiling water.  Let it sit for 30 minutes, then flushed it both ways for another 10 minutes or so.  I did it in the driveway with the nose pointing up, then filled the core with coolant mix and quickly put the hoses back on.  Reinstalled the resivoir filled up and ran it for 20 minutes with the cap off to purge air out.

 

i now have +160 degree air out the vents 

 

[mjeff87]

5 hours ago, Manche757 said:

MJ

I have only luke warm heat on an 89 MJ.  I am on coastal VA and it does not bother me that there is  little heat. The dashboard temp gauge only reads about 120 to 125 when warmed up. I assume either the gauge is stuck open or a prior owner removed it altogether.  mjpete, when warmed up, what temperature does your gauge show?  Is it inline with the 155 you get coming off the engine?   30 year old gauges and sensors.

 

For anyone, what were the original stock thermostat ratings and what are several of you running if not the factory spec one?

 

This is on my KJ, not an MJ.  I'd say if you only have 125 degree coolant, your thermostat is inop.  Could be the gauge/sending unit also, considering the age, but if you don't have good heat in the cab I'd suspect system issues (thermostat).  If the engine doesn't get hot enough it won't come out of open loop operation and won't run very efficiently.  Contrary to what many think, the t-stat functions to keep the engine warm enough to operate correctly, not to keep it cool

[HOrnbrod]

1 hour ago, mjeff87 said:

I got it

 

i went medevil on the core.  Pulled the expansion tank and core hoses like I normally do, but forward and reversed flushed it for about 20 minutes.  Then I blew the core out with air and filled it with a mix of white vinegar and boiling water.  Let it sit for 30 minutes, then flushed it both ways for another 10 minutes or so.  I did it in the driveway with the nose pointing up, then filled the core with coolant mix and quickly put the hoses back on.  Reinstalled the resivoir filled up and ran it for 20 minutes with the cap off to purge air out.

 

i now have +160 degree air out the vents 

 

What a major PITA that was Jeff - I admire you for tracking it down. Is this a KJ-only thing or only your KJ? If it affected them all you would think there would have been a tech recall, TSB, or some general notification for KJ owners.  

[mjeff87]

Yeah, it's a KJ thing.  Stupid design......the core is level or slightly higher than the expansion tank and traps air.  It's also not really able to be flushed due to the way it's designed.  If there's crud, or like in my case an air pocket, inside it, coolant bypasses the entire core and just exits as quickly as it goes in.  That's why I tried flushing it with the nose pointing upward in my driveway...I think that was the real "trick" that worked last night.  LOL.

[mjeff87]

Annnddd......wouldn't ya know it.  Jeep drove fine all night last night and the whole way to work this morning.  Went out at breaktime to run to Lowe's and have a misfire on #6.  I already knew what it was, I pulled the coil pack off the plug and it was dripping wet.  The plugs on the 3.7 screw directly into the top of the head and are pointed straight up (#6 is directly below the heater core too).  I literally FLOODED the entire top of the engine last night in my flush adventure, like I always do as the heater core nipples are right above the back of the engine.  I did use shop air for about 10 minutes with a blow gun tip to blow all the water out of everywhere, but enough must have collected in the plug hole to short out the coil.

 

I'm running out at lunchtime to grab a new coil.  I did blow out the old one and put it back on and the misfire went away, but I'm just going to replace it.  I'll dry it out over the weekend and toss it in the spare parts bin.

[JeepcoMJ]

The blend door actuator is usually Inop when we have issues with ours..

 

located on top of the heater box.  It has a harness extension that is accessible by removing the glovebox door and looking slightly towards the center of the vehicle.  It’s a white plug, flat, with 3 or 4 wires in it.

 

i cut a round access hole in one of ours, disconnected the blend door wiring, and manually moved it over to heat for the entirety of winter.

[mjeff87]

Any chance you could snag a pic of that hole you drilled Pat?  My blend door seems to be functioning correctly, but I know it's just a matter of time before it doesn't.  I watched one hack video on the youtube about cutting a hole in the heater box, but I'm definitely not following that moron's advice.

 

Heat is back to good, I actually had to cut it back some yesterday because it was TOO hot, lol.  And a new coil pack fixed the misfire.  I also found a receipt for that coilpack from when I replaced it last year and it has a "limited lifetime warranty", so I'm going to take it back to AA to see if they can exchange it with a new one.  Problem is I bought it from that AA with the moron store manager who initally refused to warranty the battery I bought that crapped the bed 6 days before the replacement warranty expired a couple months ago (I have a separate thread about that  adventure somewhere on here.....).  If he hassles me on the exchange I'm not going to argue about it, as I'm pretty much to blame for shorting it out  It works ok now, so I'll just keep it as an emergency spare, unless the store is willing to exchange it for me.

[mjeff87]

I did score at the junkyard the other day....they had an 02 there that was immaculate.  I was able to get that little plastic flipper pad for the rear glass which I already installed, and I grabbed the driver side door seal/weatherstripping (mine has a small tear in it that's bothered me from the day I bought the vehicle, lol).  I'll be installing that in the morning.

[JeepcoMJ]

Sorry for the delay in getting back to you,

 

New laptop arrived in the mail today.  19" HP with AMD9 processor, 8 gigs (expandable) Ram, 2TB hard drive with 256gb SSD primary, and touch screen.

 

So, spent all day downloading pics from my old phones and getting my old computers working well enough to transfer data.  I've been completely mobile for the past couple years...it's nice to have a laptop again.

 

Anywho, attached are all the pics I've taken of what I did.  they show blend door location, motor location, and connector location.  I modeled the plug after Beechcraft inspection plugs.  made it easy for future access.

 

-Pat

[mjeff87]

Awesome.  Thanks dude

[mjeff87]

AA gave me a new coil pack....I went to a different store, lol.

 

Anyone have recommendations on replacement headlights?  I'm getting old  and don't see so good at night, my stock headlamps just aren't cutting it anymore. I don't want bling-type "blue" crap, don't want anything that's rice or something out of Fast and Furious, and I don't want to blind oncoming traffic with low beams. I just want some replacement bulbs that have a good pattern inside my stock housings that throw better light. The lenses are crystal clean/clear, so that's not the issue I'm having.

I've read on the inter webs that Sylvania "extreme" and PIAA ($$$$$) bulbs are good. I have no clue what to believe, or buy for that matter....

Jeff

 

edit:. Sorry to keep posting KJ questions here, but there's so VERY little good tech info out there.. I know you guys, and trust the collective wisdom of this board.  I got nowhere else to go!  (<<that's a movie reference and one of my favorite lines....+100 internet points to anyone who can figure out where it's from.  Hint:. "May-o-naise")

 

 

[Sir Sam]

1 hour ago, mjeff87 said:

AA gave me a new coil pack....I went to a different store, lol.

 

Anyone have recommendations on replacement headlights?  I'm getting old  and don't see so good at night, my stock headlamps just aren't cutting it anymore. I don't want bling-type "blue" crap, don't want anything that's rice or something out of Fast and Furious, and I don't want to blind oncoming traffic with low beams. I just want some replacement bulbs that have a good pattern inside my stock housings that throw better light. The lenses are crystal clean/clear, so that's not the issue I'm having.

I've read on the inter webs that Sylvania "extreme" and PIAA ($$$$$) bulbs are good. I have no clue what to believe, or buy for that matter....

Jeff

 

edit:. Sorry to keep posting KJ questions here, but there's so VERY little good tech info out there.. I know you guys, and trust the collective wisdom of this board.  I got nowhere else to go!  (<<that's a movie reference and one of my favorite lines....+100 internet points to anyone who can figure out where it's from.  Hint:. "May-o-naise")

 

 

 

 

 

Try the CRD section, its more active and has more owners who actually wrench:

http://www.lostjeeps.com/forum/phpBB3/viewforum.php?f=5

 

 

[HOrnbrod]

1 hour ago, mjeff87 said:

 I got nowhere else to go!  (<<that's a movie reference and one of my favorite lines....+100 internet points to anyone who can figure out where it's from.  Hint:. "May-o-naise")

 

I think from one of the few movies I actually liked, An Officer and a Gentleman.

[mjeff87]

1 hour ago, Sir Sam said:

 

 

 

Try the CRD section, its more active and has more owners who actually wrench:

http://www.lostjeeps.com/forum/phpBB3/viewforum.php?f=5

 

 

I'll take any good tech I can find, lol.  Thanks!

[mjeff87]

25 minutes ago, HOrnbrod said:

 

I think from one of the few movies I actually liked, An Officer and a Gentleman.

And you, good Sir, are a wiener...ER, I mean winner.

 

Have a High Life on me, I'm buying.  Lol

[HOrnbrod]

1 minute ago, mjeff87 said:

And you, good Sir, are a wiener...ER, I mean winner.

Have a High Life on me, I'm buying.  Lol

 

I am. Several in fact. 

[mjeff87]

OK, I think I have it narrowed down to 2 different bulb replacements:

 

Phillips X-treme 9007

Sylvania Silver Star 9007

 

The Phillips bulbs are cheaper, but seem to have more positive interweb reviews.  The Sylvanias are alot more expensive, some claim they have a slight blue tint while others don't (I DON'T want any blue).  And they seem to burn out quicker as they run a little bit hotter.  Some have claimed that the S/S's were actually OEM bulbs, though......as far as I can tell, I'm still running my OEM bulbs that are now 16+ years old.

 

Anyone have experience with either of these?  Right now, I'm leaning toward the Phillips.

[HOrnbrod]

Ditch the outdated halogens, Go LED

[mjeff87]

I'll admit, I was a holdout on LED's for my house for a looooong time.  I finally bit, and am glad I did.  All my garage lighting is LED, all the lamps in the house are, and so is my overhead ceiling light in the kitchen, plus the front floodlights on the house are all (low voltage) LED.  I'm a believer.

 

BUT, I've never driven a vehicle with LED lighting (headlights).  I'm not a big fan of those pure-white headlamps I see on cars...I prefer a bit cooler temp/warmer color).  You run LED's Don?  Like 'em?

 

I like the much lower power draw, and cooler bulb temps (actual temp, not color).