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-   -   keep getiing a flushing sound through my heater core (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/keep-getiing-flushing-sound-through-my-heater-core-237666/)

donny 10-31-03 11:29 PM

keep getiing a flushing sound through my heater core
 
Almost everytime I drive my car I hear a flushing sound through my heater core. I have replaced both caps and "burped" the air out the system. What the hell could be causing this?

pomanferrari 11-01-03 11:23 AM

Air in the system. Most likely the o-ring between housing and block is going bad, letting air thru.

Time to start saving for a Malloy reman at $2000 plus another grand in other parts and another grand for a specialist to do it.

FormerPorscheGuy 11-01-03 01:24 PM

I had the same probelm and mine was caused by bad coolant lines. I replaced the coolant lines and sealed up my system.

radkins 11-01-03 01:29 PM

Yup, start saving your pennies, your getting air in your system.

Kento 11-01-03 01:31 PM

Have you tried running your heater on full blast for a few minutes while driving? I know some feel that method is bunk, but it seemed to help get rid of pockets of air that I couldn't burp out of the system.

donny 11-01-03 08:16 PM

is this a common problem?
Do you guys ever hear coolant flushing through your heater core when starting the car or when reving the engine at a stop?

donny 11-01-03 08:40 PM

anyone??

bureau_c 11-01-03 08:54 PM

I got that sound on acceleration right before I ended up getting a rebuild. I definitely had bad o-rings, as I was also losing coolant to god only knows where, had trouble starting, etc.

Now, I'm hearing something similar again, only its louder than before, and I'm not seeing any of the other symptoms. Soooo...I think and hope that this time its something else.

jds

legal-z 11-01-03 09:15 PM

don't freak out about the engine until you eliminate other causes. i've had air in my cooling system three times and every time this board had me loosing sleep because i was assured it was my coolant seals. each time it was not. check every hose, cap, etc. first. each time i had a small leak developing. one that was not big enough to spout coolant at first, but would draw air into the system under vacuum. eventually, the leak would show itself and my air bubble problem would be gone.
andy

SevenHeat 11-18-03 07:39 AM

i'd agree with legal-z on eliminating other causes. i'd been having the coolant buzzer in the morning for a few days and finding no pools of coolant under the car. No smoke out of the exhaust and no boiling coolant in the overflow tank. Kept refilling it and finding air in the system the next day. Hole in the hose from AST to filler neck finally got big enough to force out coolant and i found my problem. Doublecheck everything before thinking about engine damage.

I've already had two hoses do the exact same thing. Both the hose to the filler neck and the hose to the radiator from the AST developed leaks. The AST to the radiator hose was cutting itself on the edge of the nipple from the inside from being bent at a sharp angle. The AST to the filler neck was cutting itself at the clamp from being too tight. Check all the connection points of hoses on the cooling system. Tiny holes could eventually leak air in and then coolant out.

Hope this helps.

Danny

RonKMiller 11-18-03 08:30 AM

Well, now that everyone has told this guy what his problem is......

In order to find your leak(s) you need to rent or buy a radiator pressure pump with adaptor for import cars.
You can buy it from Auto Zone under their tool rental program, and they will refund you the full amount when you bring it back. I'm sure other auto parts stores have similar policies. About $80.00, plus you will need to buy the plastic adaptor - about $10.00. Test your radiator pressure cap and AST cap first for leaks. Even if they are new. Also check for any crud on either of the necks which would prevent a tight seal with the rubber gaskets. If one or both are defective replace them with OEM, if not...

The engine has to be stone cold when you apply pressure. Pump it up to about 20psi and start looking and listening for leaks. Some of then are so small they may not be apparent for a long time, so keep it pumped up for 24 hours, even IF it is losing pressure.

You'll need to get under the car, pull off the belly pan and up top the intake and intercooler. Easy. You'll need a REALLY bright light, your nose (to smell coolant) and a mechanic's stethescope with probe extension to listen for small hisses at hose joints as well.

If you're lucky it will pee on the floor or hiss, and new hose will take care of the problem. While you are at it, replace ALL of the hoses.

If it does not pee somewhere, and when you pull a sparkplug you have water gushing out, or a strong sweet smell of coolant, you can count on $5K or so to make it all good again.
If you still can't find it you need to do the same with ultraviolet dye and a black light - a little more involved but the next step. Sometimes finding leaks can be very difficult, it takes patience. Other times they just jump right out at you.

Spend some time searching - there are volumes of information on this, but don't jump to conclusions until you have done some methodical investigative work.

bajaman 11-18-03 10:47 AM

I experienced the flushing noise in the heater when I had an 'O' ring leaking. It seems to be a pretty good litmus test of this condition, as multiple people have posted about it.
Certainly you should do a complete leak-down test, but....I am afraid you have the dreaded 'O' ring failure.
The good news is, the block seal-in-a-can works. The bad news is you can't use antifreeze with it, so it is a hassle to flush and fill and change and seal and....in my experience it didn't work to just seal it once, I had to leave it in for several months/several thousand miles.
I just recently (last week) went back to using antifreeze, I am hoping the seal will hold.
I've been listening for that dreaded "flushing" sound in the heater core.......

Str8Down 11-18-03 12:24 PM

Ron, I am a newbie and not trying to challenge you, but why 5K to make good again? Couldn't you replace the whole engine with a reman for cheaper than that?

InsaneGideon 11-18-03 04:41 PM

I occasionally hear that sound on when the engine is cold and ambient temps are (and have been) less than 70F. It goes away after the engine has run for a few seconds. I've never heard it while the engine is even remotely warm, and I don't get a coolant beeper. 3kmi ago the engine had a compression test and got 7.9 (ratio) for all 6 faces. No champaigne coolant either. Should I be looking for leaks too, guys?

RonKMiller 11-18-03 04:52 PM


Originally posted by Str8Down
Ron, I am a newbie and not trying to challenge you, but why 5K to make good again? Couldn't you replace the whole engine with a reman for cheaper than that?
No worries:

$2200.00 for reman
$1000.00 for miscellaneous parts, like new belts, hoses,
water pump, AST, gaskets, new fluids, and a bunch of little things that will break or should be replaced while the engine is out.
$500.00 for vacuum line job
$400.00 for new radiator
$1000.00 for install labor

Kind of a ballpark figure at $5k, and while you are at it replacing a clutch at this point is easy - another $400 just for the clutch. Plus labor.

All this and no mods like match porting - $300 to $500.00, eccentric oil shaft mods, and on and on.

It all adds up rather fast.;)

Str8Down 11-18-03 06:30 PM

Ok, so you were just including all the "While you are at it" stuff. In reality, a reman alone installed could be done for roughly 3k, right?

FormerPorscheGuy 11-18-03 06:47 PM


Originally posted by Str8Down
Ok, so you were just including all the "While you are at it" stuff. In reality, a reman alone installed could be done for roughly 3k, right?
All of the "while you are at it" stuff is not a recommendation, it needs to be done while the engine is out. Otherwise you will find yourself putting in a third new engine sooner then you think.

RonKMiller 11-18-03 07:09 PM


Originally posted by Str8Down
Ok, so you were just including all the "While you are at it" stuff. In reality, a reman alone installed could be done for roughly 3k, right?
Nope, if you add it all up, you're at $5,200.00 BEFORE I said while you are at it...plus tax.

Like FormerPorscheGuy said, you will be buying a third engine before you know it if you don't do the basic stuff.
I could easily put $10K into a 13B and associated components, and still not be done.

I don't think you appreciate how insanely expensive parts are for the FD3S, and how many critical parts there are to keep it running in top notch condition.
Quite frankly, its one of the most complicated cars (as far as mechanical systems) that has ever been built - and most likely ever will be built - since electronics continue to take over mechanical systems at an amazing rate.

It also requires a pretty stiff budget for a decent rotary expert to work on it (at $100.00 an hour for the dozen or so in this country that actually KNOW what they are doing) or you have to learn how to do it yourself.

All the $3,000 "engine replacements on a shoestring" are sitting idle in garages or junkyards. Why bother in the first place doing a half assed job?:cool:

Kento 11-18-03 07:20 PM


Originally posted by RonKMiller
All the $3,000 "engine replacements on a shoestring" are sitting idle in garages or junkyards. Why bother in the first place doing a half assed job?:cool:
Exactly.

The FD doth not suffer fools.

Do not try to cheap out on critical component parts. You will pay for it in spades later if you do.

SWAT81 11-18-03 07:40 PM

I get this as well but I only got 2k miles on my engine now, it does sometimes but not often. I tried burping the air out by squeezing the coolant hoses, perhaps I'll try the full blast heater while driving.

FormerPorscheGuy 11-18-03 07:42 PM


Originally posted by SWAT81
I get this as well but I only got 2k miles on my engine now, it does sometimes but not often. I tried burping the air out by squeezing the coolant hoses, perhaps I'll try the full blast heater while driving.
I don't think you have the same probelm as the other guy. Recheck all your coolant hoses, all of them.


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