Author Topic: No Heat 89n VW (Read 3736 times)

stcywll · « **on:** January 24, 2005, 11:08:21 am »

Hi
My 89 Jetta had a leak in the rad, I added two stop leaks to the system . It worked for a little while but I eventually had to change the rad.

Now I have no heat.Both hoses, the inlet and outlet hose from the heater core are hot, but the bottom rad hose is always cold.The top hose is hot, so why would the bottom hose be cold?

The thermostat is in the bottom hose,so does the coolant circulate backwards? If the thermostat was stuck closed I should still have heat?

Can the stop leak additives plug the heater core?

thanks

(Message edited by stcywll on January 24, 2005)

slybry · « **Reply #1 on:** January 24, 2005, 12:12:58 pm »

I do not know the answer to your question but just expressed my concerns over these quick fix products on 21 Jan in thread "STOP RAD LEAK". see my comments below.

Posted on Friday, January 21, 2005 - 05:15 pm:

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I do not think there are any magic cures in a bottle. I would worry about product clogging up more than just the leak you wanted fixed.

A once asked a garage to flush my rad and instead he put in some sort of magic antifreeze extender (without talking to me). This crap ended up screwing up my thermostat and wrecked all my hoses.

I do not want to see any more magic in my car.

articsteve · « **Reply #2 on:** January 24, 2005, 01:39:12 pm »

The thermostat is at the end of the top rad hose in any vehicle I have looked at. Doubt yours is any different.

Did you just change the rad and now no heat? You probably have an air lock in the upper hose or in the area of the motor where the upper rad hose terminates. Is there a bleed screw or bleed nut visible in this area?

It seems like to me that your just not circulating. Probably not enough antifreeze in the system yet so there is not enough flow thru the heater core via the water pump.

If the heater worked just before the rad change then it is not the heater core.

By the way, Rad Stop Leak products like Bars Leak are EXCELLENT. Head gasket stop leak products like IRONTITE are also EXCELLENT. They rarely clogg heater cores. It's easy to determine if it's plugged. It's not plugged, but what kind of stop leak did you use?

stcywll · « **Reply #3 on:** January 24, 2005, 01:52:30 pm »

Thanks, but the thermostat is in the bottom of the water pump attached to the lower hose in VW's.

The heat stopped a few days after putting in the stop leak with the old rad in it.I put a new rad in and still no heat.

I used Prestone stop leak. It was a brownish/grey colour.

barrie1 · « **Reply #4 on:** January 24, 2005, 07:58:27 pm »

Stcywll Welcome to the Forum. I susupect either you have air trapped in the system or a defective thermostat. Remove the Rad cap with your Heater and Fan turned to Max Hot and let the car run for around 10 minutes or so. Enough to get the engine up to full temp and wait for it to burp itself out of the rad. Keep some fresh anti-freeze handy to install as this lowers the level with the release of the air. Hope this helps.

ericthejet · « **Reply #5 on:** January 24, 2005, 08:15:50 pm »

Sounds like air to me too. Do what B1 said. Your bottom hose is cold due to a lack of coolant flow from the rad. Articsteve, ever pop the hood on a Honda? Thermo is connected to the lower rad hose BTW. :-)

No offense.

maritime_storm · « **Reply #6 on:** January 25, 2005, 12:01:49 am »

Barrie these cars don't have a cap on the rad, it's on the reservoir. My 1991 Jetta 1.6L/NA did this, the heater was actually clogged, Prestone stopleak did a great job on it, plugging the heater core that is. The thermostat isn't a fun job if your has PS, you have to remove the pump to get at the thermostat. If it's just air locked you going to have great fun getting the air out of it, leave the rad cap off, cancel or afternoon plans and make sure she full of gas, it'll take a while to get it out but that's only way you can do it.

barrie1 · « **Reply #7 on:** January 25, 2005, 12:12:20 am »

The engineers forgot to build a nice fixable design again. Sounds almost normal unfortunately as that is going to be much slower but will do the job. I have a Son-in-law who is the chief Engineer for Freightliner in Portland Ore. I have always told him to remember the guy who has to fix them as it can be very diificult on some repairs. He has had to get his hands dirty in my shop on occasion and he learned a lot from it. I know it affected his future thinking on design. Its Funny when you hear one of these design engineers curse about the design of one of their Bretheren.

(Message edited by barrie1 on January 25, 2005)

(Message edited by barrie1 on January 25, 2005)

articsteve · « **Reply #8 on:** January 25, 2005, 04:37:57 am »

Well Eric since you mentioned it I went outside in the freezing cold and in a HONDA 2002 SIR, 2L, the upper rad hose goes to the thermo. At least that what it looks like. It terminates on the shiny steel fitting that looks like it caps a thermostat and has a water by-pass hose running out of it. The lower hose goes straight into the block.

Facing the car the upper hose is on the right side of the rad and enters the right side of the motor. Lower hose comes out of the right side of the rad and crosses over to the left side of the block.

I really think it depends on the motor.

My 6.2 GM Diesel was definitely the upper rad hose to the thermo. I had a lower rad heater hose on that unit which went right into the block right at the water pump.

To be fair, I also popped the hood of the 95 Saab V6 and it LOOKS like the thermo is at the end of the lower rad hose.

87 2.4 Porsche is definitely upper rad hose to thermo with bled nut because I looked. 2.5 95 Bimmer motor is upper rad hose to thermo with bleed I'm sure of it because it's has such short hoses, but I'd need to look first to be sure.

Of all the units mentioned, only the Honda, which is the newest car mentioned, has the traditional rad cap located in the middle of the rad. The Bimmer has a side cap located lower on the side of the rad. It still needs to be bled though. The rest have plastic stand alone tanks of various designs.

(Message edited by articsteve on January 25, 2005)

articsteve · « **Reply #9 on:** January 25, 2005, 04:58:14 am »

Stcywl; so you say the heater stopped giving heat after you installed the Prestone Stop Leak and before you changed the rad.

Well after knowing that, I would say your heater core is plugged. Bad stuff that Prestone is it seems. Bars Leaks advocate here. Not much help to you now. Can you find the two ends of the heater hoses that run to and from the core? Apply some compressed air to one of the hoses and see what happens. See if fluid comes out rapidly from the other one. It should be just one long loop. Turn heater control to full hot before you do this.

Barrie suggested a mix of baking soda I believe he said. Try getting some of that in there? Or normal vinegar is pretty effective. You just need to flush that out afterwards.

Sometimes there is a heater control valve that the heater hoses connect into before they continue on to the heater core.

Or it's a matter of air in your upper rad hose like already suggested by all. Try taking off each hose at the highest end and filling them up by hand, then cover the end over and quickly jam the hose back on the fitting. That might get the system going enough that air will come out the cap eventually.

maritime_storm · « **Reply #10 on:** January 25, 2005, 05:23:34 am »

The thermostat is located in the bottom of the waterpump housing at the bottom of the engine.

articsteve · « **Reply #11 on:** January 25, 2005, 06:37:46 am »

I believe he said that. His problem it seems is either plugged core or air in rad hoses.

Maritime: Is that engine bay easy to work in? Lots of room? Where does the upper rad hose terminate? Just below the cylinder head? I bet his upper rad hose is full of air. He needs to fill it manually. Hope he hasn't given up yet and gone to a shop.

Maybe some rad flush will purge the heater core once he gets it circulating. But you would think it would overheat on him or the temp gauge would move up if he had a gaint air lock.

stcywll · « **Reply #12 on:** January 25, 2005, 07:56:41 am »

Hi
Thamks for the replies.

I tried rad flush but that did not work.

It doesnt overheat.

There is alot of room in the engine bay.The upper hose terminates in the front of the head.And I will try some of the other sugestions tonight.

barrie1 · « **Reply #13 on:** January 25, 2005, 01:44:25 pm »

I use the Baking Soda to clean a Rad right out of all the sludge and corrosion. Put a large box of it in the rad and drive it for a week before you flush the system out. It really cleans everything out and in very quick time as well. After Flushing thoroughly then add your new stat and anti-freeze.

articsteve · « **Reply #14 on:** January 25, 2005, 04:41:19 pm »

Ok, so are you zeroing in on a pluged heater core? If so, you really could use some compressed air. I would find the two heater hoses; flow in and flow out, right? Make sure that the the hose(s) don't first teminate at some sort of heater control valve before they disappear into the firewall.

Turn the heater control to full heat, I'd get rid of all the fluid in both heater hoses, elevate them the best you can and pour DRANO (or similar product)into them and let sit. You might need to buy a coupler and some extra heater hose and extend the length of the hoses. What size hose? Less than 3/4 inch? $1.29 @ foot.

Compressed air would be best to try first on one of the hoses. It would certainly displace the fluild in the hoses so you could get some drano in them.

The problem with rad flush is that if the heater core is pluged then nothing will circulate through it. You need either to compress air through it to get some sort of pathway happenning or use the drano to disolve a pathway through it.

The goal is to avoid removing the heater core.

denny · « **Reply #15 on:** January 25, 2005, 11:53:17 pm »

Hi from what I have experenced befor I would start with replacing the thermostat that stop leak shut like barsal will or can plug the heater core. I would also flush the system backwards to remove any unwantabls... And as what Articsteve said about drano/ I use C.L.R it won't eat rubber...

articsteve · « **Reply #16 on:** January 26, 2005, 11:28:40 am »

CLR is useless. Ordinary vinegar is hundred times more effective. The plastic container that holds CLR must cost more than the CLR liquid itself. They must make a fortune on it.

The dude needs something heavy duty like Drano. Bars Leak does not plug heater cores. Bye

stcywll · « **Reply #17 on:** January 26, 2005, 11:39:29 am »

Last night I took the inlet hose to the heater core off snd started the car,and coolant came gushing out. Then I put that hose back, and took the outlet hose off and started the car. I got a trickle coming out.

I dont think baking soda would remove a chemical goop in the core? Drano sounds like a good idea.

Thanks

barrie1 · « **Reply #18 on:** January 26, 2005, 10:41:31 pm »

Wish you Luck with your problem.

maritime_storm · « **Reply #19 on:** January 27, 2005, 03:22:40 am »

The Drano sounds like a real bad idea, anything that corrosive would have a healthy appetite for things like headgaskets, radiators, and the heater core itself. The baking soda would be far safer.