Determined to get the heater working again

[skim464]

Hi

I am on a mission to get the heater work again. After extensive diagnostic, I think the heater core is partially plugged up. I tried flushing it with chemical several times to no avail.

So.. I will go ahead and change the heater core but there is this one thing that I am not sure about.

1. Evaporator... Do I need to unplug it from the main A/C Pipes which leads to evac and recharge the A/C System? or can I work with the evaporator still plugged in?

P.S.
How long would it take? 7am-5pm enough time??

[skim464]

Sometime I wonder whether I am buying a car to drive it or to fix it...

[BThomas220]

I just did mine this past month. It sucked ass. If you are flying solo with no one there to instruct you, you will probably have 15-20 hours in it.

As far as the A/C goes, you have to evacuate the system. You will be moving the hvac box away from the firewall to install the heater-core. There is no way to do this with the A/C line still attached.

If you are like me you bought the car to drive. Only problem is, they have other plans.

[skim464]

man.. evac/recharge the a/c system would be an additional cost :(

[BThomas220]

man.. evac/recharge the a/c system would be an additional cost :(

How bad do you want heat?

[TylerDSAudi]

My heater wasn't blowing hot air at all barley towards fall. I did the heater core flush for 10 mins and it works great now can't have my care over 21 once it's warmed up or it's really hot! Haha

From what you tell it sounds like you might have a bad core and that's a pain, a lot of work to get to the core and replace it. There is 1 DIY I seen online when I thought mine was went and I was scared to even try to get at it!

Good luck!

[Artiemas]

Heater core change on the A4 is...A lot of time. If I had to, and I've done both, I'd do control arms which is 16 hours, before I did another heater core job.

[walky_talky20]

I *just* bought one of these thingys the other day:
http://www.amazon.com/OTC-6043-Blast...ords=blast+vac



Our local radiator repair guy used one of these type of devices on a stubborn B5 2.8 car we had. We tried flushing it with a garden hose several times (every winter) for this customer. It would work "ok" for him, and he'd usually come back again. So we finally took it over to the radiator guy, thinking he would use some awesome chemical flush machine or some-such. Nope. He had this special gun that hooked up to a garden hose and shop air. Some expert manipulation of the dial and trigger and a good amount of crap was dislodged from the core. Heat works good as new.

My B5 heat is working great, but my B3 90q has very little heat. I want to use it as a winter beater, but that's a deal breaker if the heat doesn't work. Both hoses are piping hot, just very little heat delivery to the vents. Center vent is "warm", all other vents are "barely warm". I'm quite certain the air flaps and everything are fine (they are manual, not automatic). The core is just partially plugged up from sitting for 6 years with rusty coolant in it. The hot water is "short circuiting" through the core, taking the easiest path. I will be using the BLAST-VAC on it as soon as it comes in and will let you guys know how it goes. I'm very optimistic: how can it NOT work with a name like the BLAST-VAC!? Seriously.

[BThomas220]

In for EXPLODED Heater-Core!!!

[walky_talky20]

I'll make sure and get some pics of the carnage.

[skim464]

man I wish I have one of that

[walky_talky20]

I'm really hoping this is the "magic bullet" for fixing Audi heater core issues. We've done lots of back flushes and even 1 hour treatments of Drano or CLR (which never seems to do very much). The ease at which or local Rad guy fixed the persistent heat issues in that 2.8 with his little water/air gun was exciting.

The thought had crossed my mind the last time I flushed the core in my B3. I got everything hooked up and pulled the trigger on the garden hose. The hose had been off for a while so the air spurted through the hose quite aggressively for the first little bit. I thought to myself "hey, it seems to work better like that!". This gun would appear to do just that: pressurized spurts of air *with* the water, on demand. I guess I'll find out soon enough.

[BlackLock_A4]

Heater core change on the A4 is...A lot of time. If I had to, and I've done both, I'd do control arms which is 16 hours, before I did another heater core job.

Hold on, hold on... It took you 16 hours to do control arms? Was the heater core job long, or just straight up hard? [tehehe ]

[Scientist]

I'll make sure and get some pics of the carnage.

Something like this? (Hope it shows)

http://www.facebook.com/photo.php?fb...type=3&theater

[walky_talky20]

My comment was in reference to BThomas's suggestion that I was going to a-splode the heater core with my fancy blaster gun. (I've already decided that this tool will be known around the shop as "the blaster"). Seeing as this gun is designed for this task, I don't think there is much to worry about. I'll get some pics either way. Maybe some video of whatever black magic happens when I pull the trigger.

[Artiemas]

Hold on, hold on... It took you 16 hours to do control arms? Was the heater core job long, or just straight up hard? [tehehe ]

My car has been in the North East all it's life, and has had very little maint. done to it in general. One of the pinch bolts broke, so that took an hour alone, and it was my first time really ever doing something like control arms. The time provided also includes breaks that I took along the way, an dletting PB blaster set it while I worked on my motorcycle.

Also, that air/water gun...I want it for water gun fights. I'll just strap an air compressor to my back.

[walky_talky20]

Ok guys, the BLAST-VAC just came in the mail today. It's a little smaller than I thought, but makes it easy to hold with 1 hand.

One of our mechanics has a JDM 2JZ-GTE he will be putting in his '83 Hilux pickup. It's being converted to single turbo and he's figuring out all of his oil lines and such at the moment. (Yes, he went all Picasso on his compressor cover). The engine is in mint condition with less than 50k miles. He noticed a little bit of orange sediment in one of the factory turbo coolant lines. He connected the garden hose and flushed out the block. A little bit of orange water came out, then it ran clear: good to go.



Enter, the BLAST-VAC. We decided to hook it up to see how it worked, not expecting to get anything else out of the little 2J. Turn on the water valve and a couple pulls of the trigger: TONS of BROWN, RUSTY CRAP came out of the engine. We had to put hoses on each of the open coolant lines because the water would spray so far and high. It could hit the roof of the shop! It was insane. For 5 solid minutes he rinsed loads of brown crap out of the cooling system, after a regular garden hose flush had made it run clear already. It was quite a sight to see the engine puking out all this nasty crap. Chunks of stuff, even. (I regret not getting photos of this. Sorry).

Anyway, I'm very excited to try this out on my B3 heater core tomorrow morning. This thing definitely seems to work very well. It is quite impressive to behold.

[Nduetime]

...(I regret not getting photos of this. Sorry).

Anyway, I'm very excited to try this out on my B3 heater core tomorrow morning. This thing definitely seems to work very well. It is quite impressive to behold.

Is there anyway you could take photos of what comes out with a regular garden hose then with the Blast-Vac? I think it would be very beneficial to the community. If not, no big deal. Just throwing out the suggestion. Good luck tomorrow.

[BlackLock_A4]

Is there anyway you could take photos of what comes out with a regular garden hose then with the Blast-Vac? I think it would be very beneficial to the community. If not, no big deal. Just throwing out the suggestion. Good luck tomorrow.

I'm guessing it's already been flushed/ pressurized with a garden hose - that's why he bought the Blast-Vac. Just my guess.

When my heat wasn't working I blasted it with a garden hose and a couple nice chunks of snot came out. I'm talking quarter - key fob size. I was so excited to go drive around with hot heat. However, it didn't increase the heat as much as I expected. Still a cold guy over here. True story from (2) winters ago... Guess I don't want heat as bad as OP.

[BlackLock_A4]

Although, I do have to say that i'm looking forward to the results of this bad-boy.

[walky_talky20]

Okay, so...results time.

First here is the victim, my 1988 Audi 90 quattro (has seen better days):



Here is what we are working with:



A nice white bucket (all the better to SEE you with), some freshly squeezed bubble gum juice, 9 feet of 3/4" ID heater hose from AutoZone, garden hose, shop air hose, and last but not least: the BLAST-VAC.

As requested, I first used the garden hose method. This sprayer has a pretty aggressive pattern (not comfortable to get sprayed with at point black range):



The hose basically just pushed out my G12 and few tiny pieces of sediment. Ran clear after a few seconds. Aggressive pulsing did not have any measurable effect. Here's what I got out of it:



Now, time for the "big guns". Here's a photo of the setup:



Upon turning on the water flow, you get a nice gentle flow from the BLAST-VAC, like you would from a hose without a sprayer on it at all. Nice and gentle....and then POW! One little pull of the trigger releases a veritable torrent through the core. I took a quick video of a "trigger pull" so you guys can kind of see what happens. It is *very* necessary to hold the end of the hose or else it will flail in spectacular fashion. In the video you can see I held it up the hose a little bit so you can see what I mean - the blast misses the bucket entirely.

https://www.youtube.com/watch?v=2sTWPO7IefA

That recording was toward the end of the process. But in the beginning, after you pulse the trigger the hose will run straight rust brown color for a bit. Here is what I got after just 2 pulses of the trigger:



And a closeup of the nasty stuff that came out. Some of it was rust dust, but a lot of it was basically like little rocks and stuff. Very hard material. (Yes, grubby fingerprints...NO STEALING MY IDENTITY):



Here is my first bucket after the blasting:



I think I had 2 buckets that were rusty brown like that, and then it started to clear up, with just some sediment still coming through:



Bucket number 4 was pretty clean. A very small amount of stuff, so I figured I'd stop there.



Overall, I was very impressed with the Blast-Vac. It got lots of crap out of the core that the garden hose would never have touched. I probably got what would amount to an entire handful of those rocks! During the usage I didn't ever feel like I was going to damage anything, either. The blasts are powerful, but it's more "agitate" than just straight pressure. The hose is completely open at the outlet, so it isn't like much pressure can really build inside there anyway.

*However*, this was kind of one of those "the operation was a success but the patient died" scenarios. My heat is somewhat better, but still not what it should be. After some dashboard surgery I have discovered some problems with the HVAC duct-work. The factory install relied on some foam product to seal some laughably large gaps in the duct connections. All of that has deteriorated and left theses gaps open. Basically, the system is losing/diluting my heat before it actually gets to the various vents. I've patched what I can with some windshield goop, but I can't reach all of it. It seems the heater core, while apparently full of some non-water items, was not the major issue here. But having it at optimum performance will at least help to cover up the other faults.

[Artiemas]

I may or may not get one of these. They're pretty cheap, too, from what a quick 5 minute search did. Like $55 on Amazon. Impressive stuff this thing does, and it certainly gets out pretty much everything. I've been wanting to flush my coolant system, but I may just wait for this baby to come for christmas.

[BThomas220]

Very cool, I am glad that it didn't esplode on you!!!

OP, you should get one of these things, if it doesn't work you can resell it here on the forum and then do a heater core swap.

Walky-Talky Thanks for putting that up, seems like the gun has got some kick.

[walky_talky20]

Oh, I forgot to mention that it makes an *excellent* water gun...more like a water assault rifle. The guys at the shop made sure to test out that feature!

[A1 A2 German]

IN . for more results.

I was literally JUST posting a thread about my heater not working and saw this. Bummer there was another element that contributeted to the lack of heat so we ended of with mixed results.

Any one else? Or Walky, I'll pay shipping to and from and I'll post the results . You know you want to! Any one else grabbing one?

[walky_talky20]

Yeah, I was disappointed that I didn't get more clear-cut results as well. The device isn't really mine, so it isn't something I can loan out. It's a shop tool and being the winter season I'm sure we will get some more use of it before long. I'll definitely post more results as we use it.

[bmann]

In for more blast vac results. I have pretty weak heat and may give this a try over the holiday break. I've already had a shop try to flush the heater core last year, with mediocre results but on those super cold days I want hot heat!

[walky_talky20]

We should be flushing the heater core and engine block of a 200k mile used up Toyota Corolla Wagon (read: Race Car!) with some nasty deposits in the cooling system at some point in the next few days. I'll try and grab some photos. So far no Audi heat complaints have rolled in. Although we do have Passat 2.8 with an *overheating* problem, lol.

[walky_talky20]

The Corolla Wagon cooling system flush happened today, earlier than I had anticipated. However, the system was somehow spotless in that car despite having 236,000 miles and the same green coolant in it since at least 1998. The nasty deposits appeared to only have been at the aluminum hose connection, and not throughout the engine. It flushed out a very small amount of light brown water, and that was about it. This is good news for the race car aspect, but I was hoping to have some more exciting news from the Blast-Vac Round 3.

[walky_talky20]

Just wanted to update on my heat situation. After driving this car to work a few more times, and nearly losing some fingers and toes, I decided to dive into the dashboard to see what the heck was going on.

I found a great DIY guide on removing the heater core in B3/B4 chassis. It actually wasn't that bad to take apart. Took about 2 hours to get to this point:



At which point I saw this:



And I was like, "Dude, check out my blend door, yo." I'm pretty sure the blending happens 'more better' when there aren't holes in it and stuff. lol. Or perhaps not so "lol" seeing as it's like a weekend of dashboard surgery to fix this mess. I have absolutely no idea why Audi decided to make these doors like this. If they were solid plastic with foam on the edges to seal them, they would still work okay when the foam disintegrates. But that would be way too logical, I suppose.

Anyway, the project for today is to acquire some foam and sealant to rehab my little blend door. I'm now quite certain the heater core in this car is fine, however the 25 year old plastic end tanks are showing some heat cracking, so I'll definitely be spending the 20 bucks on a new heater core while I'm in here. This thing better roast me when I'm done.

[bmann]

Oh no, I hope mine doesn't have that problem. I just got around to ordering the Blast Vac yesterday, so sometime in the coming weeks I'll get to try it out. Since my b5 is my daily driver, I can't start a project and not finish it basically the same day. :P

[walky_talky20]

Luckily for the B5 platform they (finally) got some sense knocked into them and went with plastic doors *without* gaping holes in them. So I don't think you have anything to worry about there.

It is interesting to note that the design of the heater box itself is the same between the B3, B4 and B5 models. In fact the part number for the heater core itself is shared between them. The overall box design dates back all the way to Mk2 Golf/Jetta, or perhaps even earlier. The way that Audi/VW stick with a single design (sometimes in spite of it's flaws!) for decades is pretty neat sometimes.

[redline380]

sometimes i get very envious of mechanics. you guys get to buy all the cool, special tools and actually get to use them. i go and spend some $120 on a ratchet and it sits in my box for weeks at a time. i just stare at it imagining ways i could use it. can you let me job shadow you for a couple weeks? my tools need to get broken in a bit and depsite me owning an audi, they rarely get used. ironic, i know

[walky_talky20]

^Are you talking to me? Maybe you missed my signature, but I'm "not a mechanic". You're free to job shadow me any time though: I'm an IT guy.

I will say that an easy way to get some more use out of your tools is to buy a *second* Audi. Preferably one that is old and has tons of miles. Then you will have a never ending laundry list of crap to fix on both cars, guaranteed.

[redline380]

I will say that an easy way to get some more use out of your tools is to buy a *second* Audi.

I would, but I plan on making this one my second audi one day. but i just dont get much use out of all my specific audi tools. at the rate im going, i wont ever be able to sell my b5 as ive got too much invested in tools alone. like i kinda almost wish my headgasker were to go out just so i could use my headbolt tool. and it would be fun changing it. on the shitter today, i got the idea of changing it out just for fun, even though it only has 3000 miles on it. im kinda lame

[Artiemas]

I would, but I plan on making this one my second audi one day. but i just dont get much use out of all my specific audi tools. at the rate im going, i wont ever be able to sell my b5 as ive got too much invested in tools alone. like i kinda almost wish my headgasker were to go out just so i could use my headbolt tool. and it would be fun changing it. on the shitter today, i got the idea of changing it out just for fun, even though it only has 3000 miles on it. im kinda lame

I feel the same way.
"I bought all these tools...And I rarely work on my car." :| I think about breaking stuff on my car just for an excuse to fix it.

Though, the 30vs cam lock bar is a mighty nice wall hangar.

[walky_talky20]

Just wanted to give a final update on my little project.

I completed the repair on my blend doors. Here are the supplies:



I chose 2 different colors so if the foam ever comes apart, I will know which one it is. Also, it makes for better photos:





I took the opportunity to change the heater core. As you can see the top plastic tank was getting a bit brittle looking.



I'm pretty certain it is the original heater core from 1988. Mostly because to top tank says "West Germany". I thought that was interesting:



Anyway, the car has TONS of heat now. I was literally afraid it was going to melt the vents. Even hotter than the heat in my B5. Now I just have to get the car aligned so it isn't scary to drive on slippery roads, and it should be a pretty good winter beater.

Update on the BLAST-VAC: A Nissan Pathfinder came in with nearly zero heat. Coolant was disgusting - probably the beginnings of a head gasket failure. Gave it the blast vac treatment, no chemicals or anything. Heat works fantastic. +1 for the Blast Vac.

[bmann]

Here's a photo of the setup:



Overall, I was very impressed with the Blast-Vac.

I used the Blast-Vac method a couple days ago and my heat is pretty comfortable now, at least down to 25°F, which is as cold as it's been since. I didn't see a large amount of sediment or rust, probably because my heater core had been flushed recently, but some stuff did come out. I flushed and back flushed a couple times until I had filled up a 5-gallon bucket with water. I used a 6 gallon air compressor with a max of about 150 psi. Our faucet is pretty high powered so I couldn't even turn that all the way on or the hose connections would start spraying water.

The heater core flush DIY I read stated using a 7/8" hose would have been easier since the 3/4" is pretty tight, but with the Blast-Vac you'll want to use the tighter connection to keep it from losing the water.

[jursch2211]

Necro bump..... can this be tool be connected to the coolant hard pipe to clean out the block of any sediment or could that cause problems. I have a thermostat that I'm replacing along with the J plug and want to use this since the shop I work at has this tool.