Heater Core Problems

[91Lexuser]

Hi,

I was wondering if anyone of you have had any experience sealing a leaky heater core with Blue Devil Engine & Cooling Sealant by Universal Products!

http://www.gouniversalproducts.com/product_overview.html

This is for a 1991 LS400.

Thanks a lot!

[larryp]

No experience with the product but i would be very leery of adding that to my cooling system.

[91Lexuser]

Thanks Larryp!

Well, faced with a situation where the dealer charges $105/hr and estimates that the job will take a minimum of 10 hrs, one would start looking for other options. Mind you that you still need to add the price of the core itself.

I thought I found the core being peddled on the net for $66, but then I discovered that they're a bunch of crooks. That's a topic for another day, though!

The car has over 230,000 miles and I'm waiting to celebrate my quarter of a million mile on it.

Now, with that in mind what would you do?

[Harky]

Now, with that in mind what would you do?

Option 1 - Obvoiusly, search out an indie mechanic that charges a more reasonable hourly rate...

Option 2 - If you are handy, you may do some investigation on your own to verify that it is indeed a core leak and not a leak at the hose connection to the core. This may be a much less expensive fix.

Option 3 Bypass the heater core circuit to eliminate coolant flow thru the core. (Assuming that AL winters aren't too severe...)

Option 4 - Dump in the "stop leak" and pray that it doesn't plug up your radiator or idle control valve circuit or your PCV circuit, etc, etc.

[VBdenny]

I have never seen leaky heater cores get any better. Usually the first sign of trouble is the inside of your windows developing a fog. Heater cores are located in very difficult places to access which is why they charge so much. I suppose if this happened to my car I would probably investigate how to change it out myself. My second choice would be to find a garage that charges less per hour such as a Toyota dealer. Some Toyota dealers will not work on a Lexus but some will. I really doubt the stoip leak will work anyway.

[larryp]

Like you, i know at this point any major repairs are going to represent a major portion of the total value of the car. If you plan on keeping her another year you'll have to get 'er fixed. However, as Harky suggested, bypassing the heater core for the summer might be a good option to "fix" the problem temporarily. I have had the pleasure to replace 2 heater cores in the last 3 months (F150 and Monte Carlo) and it is a major pain - not technically difficult - just plain hard to get to everything. On the F150 you have to remove entire dash. If you have any mechanical skills you could do probably do it yourself and save a ton of money.

I'd bypass her for now and plan to fix her myself later (or at least find a ggod indie mechanic).

[plexus914]

Removing the heater core is not that difficult because you do not need to remove the dash.....just pull the core off the heater housing:

LS 400

1. Disconnect the negative battery cable. Wait 90 seconds before doing any further work while the airbag system de-energizes.
2. Disconnect the negative battery cable.
3. Drain the cooling system into a clean container for reuse.
4. Remove or disconnect the following:
   - Undercover and the No. 1 safety pad-to-instrument panel screws and the panel at the driver-s side
   
   - No. 2 heater-to-register duct

   - Heater core-to-heater housing screw and clamp

   - Heater hoses from the heater core

   - Heater core from the heater housing

   - Discard the O-rings

   
   
   
   
   

   
   

   
   

   
   

   
   

   
   

   Fig. Exploded view of the instrument panel-LS 400

   
   
   
   
   
   

   
   

   
   

   
   

   
   

   
   

   Fig. Exploded view of the heater core, heater/air conditioning housing and related components-LS 400

   More MODELS:

   http://www.autozone.com/autozone/repairguides/Lexus-Car-ES-IS-LS-1998-06/Heater-Core/Removal-Installation/_/P-0996b43f803790e1

   
   
   
   
   

[Charles Coleman]

I have wsyet leaking in my back seat puddle of water.   When O drive I can hear water sloshing under the passenger seat.   What could be the problem.  Heat is still working..

[sha4000]

On 12/16/2019 at 5:06 PM, Charles Coleman said:

I have wsyet leaking in my back seat puddle of water.   When O drive I can hear water sloshing under the passenger seat.   What could be the problem.  Heat is still working..

Your sunroof drains are most likely clogged with junk.

[Replace leather seat cover]

My wifes original HEATED leather seat covering that is perforated on her 08 es350 has gone bad. I have gone on eBay and found one to replace it but it is not perforated - would it work? it is not just the leather but it has the 3 inch foam as well.  

[vissine]

I would never use those sealants. It never works and mostly creates undesirable conditions in the engine.