yudkib

My evaporator is leaking like a sieve and needs to be replaced. I haven't decided if I'll use my shop or attempt the extensive DIY myself. Alldata quotes like 6.5-7 hours which is super reasonable. I'm planning on a Denso evaporator.

My mechanic strongly recommends doing the heater core during the job. No high-quality aftermarket is available, it looks like Lexus or bust, and they're around $400-500 direct. Plus he'll have some markup.

I understand the wisdom in doing the heater core at the same time, but there's 3 mitigating factors here:
1) The core itself looks pretty robust with aluminum end tanks
2) I haven't found anyone on CL or LOC who has ever complained of a leaking heater core, unless it was an aftermarket one they installed while doing the evaporator... Literally no one ever.
3) Its extremely expensive

I get that "an ounce of prevention is worth a pound of cure" but is this really necessary? If any of those 3 things were untrue I would probably bite the bullet. But this doesn't seem like a maintenance item, and without plastic end tanks I don't see why it would suddenly start leaking after the job. Any advice? What would you do? Thanks.

salimshah

When you state leak .. doe is mean the condensate? The solution for the condensate leak is to simply reseal the plastic clamshell.

The process can snowball from .. since I am here might as well replace this and that.

Salim

yudkib

No, I meant other people do not say their heater cores are leaking coolant.

Nad1370

Heater core does have to come out to access the evaporator.
Most i’ll do is clean out the fins and flush the core with water while its out.
I would just be careful on the lines of the heater core upon install.

What exactly is wrong with your evaporator?

If i was going to replace a part while im in there, it would be the expansion valve.

yudkib

Yeah I know it’s all part of the big air handling box. He’s just worried that disturbing a 18-20 year old radiator filled with hot coolant will just entice it to leak. Which makes sense, but seems a little over-conservative given that there doesn’t seem to be people complaining about having that issue.

The car is leaking Freon at about 12 oz / week. Neither me nor the mechanic was able to spot the dye that was added, so we both assume that’s what it must be.

Nad1370

Are you guys using a UV light to find the dye (leak)?
Shine it up the AC drain hose.
Either inside the vehicle or outside where it actually drains out.

But either way, it sounds like you guys are in the right track if no dye leaks found externally.
Either the evaporator or the expansion valve o-ring are leaking.

yudkib

Shining it up the condensate drain is a good idea. Didn’t think of that. No guarantee but worth a shot. I take it as you see no need to do the heater core as preventative maintenance while one of us is in there?

yudkib

Oh... yes of course we both used the UV lights. And yes we’ve checked the sight glass with the light to be sure coolant/ dye was circulating. And yes the AC ran cold when the charge was fresh, and yes the car heats so it’s not the compressor condenser or mixer servo. There’s nothing else it could really be other than the evaporator, especially because it’s leaking so much. Just a question of whether I’m buying a heater core to go with it, and whether I’m doing it myself or paying him.

yudkib

One more bump, have to decide by Monday. Sounds like I’m going to tell him to reuse the old core...?

sktn77a

iTrader: (2)

On a car this old, I'd risk it.

yudkib

Thanks. She called me an hour ago to tell me someone ran her into a jersey barrier, so point might be moot anyways.

salimshah

Oh Oh! Just deal with the important stuff and hopefully the trivial are left at the end.

Salim

salimshah

The bump helps in forums where old stuff falls off the first page by the new posts. I would suggest just monitor the first window and if your post is there the bump will not be to your advantage. The unread posts will always appear bold to the other members.

Salim

Audiqv8

If it was my car I would make sure that it is the evaporator that is leaking. UV dye is great, but it doesn't really compare to a sniffer.

yudkib

Are the cheap sniffers that good? I thought about getting one but I figured if all the mechanics used dye there was probably a reason