jhammerrx7

iTrader: (5)

I am renting a coolant pressure test kit this weekend to find out where my coolant is going.

Any tips or tricks to doing this?

-Josh

jhammerrx7

iTrader: (5)

Well, I wasn't able to rent the pressure tester (didn't have the correct filler neck adapter) so I am taking my car into a local shop to have a pressure test run on it.

I am nervous as hell. Expecting the worst.

It will really suck if there is a pressure loss because I can't find any leaks. So it means it could be going into the engine.

Regardless of the pressure test I am going to run the champagne bubble test later tonight.

Wish me luck, cause for some reason I think I'm screwed.

scotty305

iTrader: (2)

If possible, I'd test the system while the car is running also.

For instance, install the pressure tester when the motor is cold, and pump the pressure up to 16-18psi, to test if you've got any leaks.

Then, remove the pressure tester and install it at the filler neck (allowing the OEM cap on the AST to regulate system pressure) and start the motor. Let it warm up, and measure pressure as the temperature changes. Compare your data to the test that has been documented here:

http://www.fd3s.net/cooling.html
(look for a graph)


Good Luck,
-s-

jhammerrx7

iTrader: (5)

Well, I got some bad news.

We pressurized the system and after a couple of minutes it did in fact lose pressure.

We couldn't find any leaks, but we did notice that on a cold start up there was a little white smoke coming from the turbo/downpipe gasket.

I have a little exhause leak there, and the guys at the garage think the coolant may be draining into the turbo.

So just to start eliminating stuff they clamped the turbo feed and return coolant lines and re-pressurized the system (engine not running on either test) and the pressure did hold for longer and not as much was lost.

So, I don't know my next step. I have not done the "bubbles test" yet.


What should I do? How can I tell if my turbo maybe leaking coolant?

Any help is greatly appreciated. I feel like I've been kicked in the *****.

jhammerrx7

iTrader: (5)

After doing a little reading it seems that coolant draining from the turbo into the downpipe is highly unlikely.

So, besides from tearing the engine apart, are there any definitive ways of checking if an o-ring is bad?

jhammerrx7

iTrader: (5)

I just got the car in the air and I can't find one place where coolant would be leaking. Should I go ahead and flush the system and install the new t-stat anyway?

I need some help guys.

Josh

jhammerrx7

iTrader: (5)

Ttt

gracer7-rx7

iTrader: (16)

Need some clarification. Are you saying that you are loosing coolant but can't find a leak? If so, how much are you loosing and how quickly are you loosing it? Did you lose all pressure during your test or some percentage?

WaLieN

An easy indicator for me was to turn on the car, let it do a few fan cycles, then shut it off. I let it sit over night. In the morning, I turned the motor over by hand with the leading spark plugs removed. Coolant came out. It was as simple as that.

jhammerrx7

iTrader: (5)

Yes, I'm losing coolant and looked under the car for quite a while last night and can't find any spots where coolant would be going.

After burping the system and making sure coolant was coming out of the throttle body line I would then top off the filler neck.

After 10 minutes or so the coolant would be down to where the radiator hose attaches to the filler neck. It seems like its always taking coolant and never completely filling or levelizing.

I drained the radiator last night and I need to install the new t-stat today.

I may also replace both of the radiator coolant hoses today.

I still need to locate the drain plug on the block to drain the coolant from the engine.

jhammerrx7

iTrader: (5)

If there is in fact coolant sitting in your engine shouldn't it start really choppy and smoke?

Because my car starts fine the first time every time.

And I haven't noticed any smoke except a little puff where the turbo and downpipe connect.

Mahjik

iTrader: (1)

It all depends on how much coolant would be leaking. If not much is leaking (yet), there might not be any smoke at all.

jhammerrx7

iTrader: (5)

Thanks for the heads up.

Is there any definate way of checking your o-ring besides taking the engine apart?

scotty305

iTrader: (2)

It's good that you've done the pressure test. I would check a couple more things:

1. Closely inspect the turbocharger coolant lines: http://www.robrobinette.com/turbo_lines.htm

2. Follow WaLieN's advice, it's a very easy way to see if coolant is seeping past the coolant seals.

3. There's no good reason not to replace all the coolant hoses... I've been told it costs less than $200.
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/all-coolant-hose-part-numbers-331644/

4. Even if you're doing a good job of burping the sysem, consider trying a Lisle coolant funnel. It's amazing how much air you can still remove from the system even after burping it properly. https://www.rx7club.com/3rd-generation-specific-1993-2002-16/radiator-cap-funnel-eliminate-air-bubbles-342309/

-s-

jhammerrx7

iTrader: (5)

I think I may have found the leak. The coolant hard line that goes down right below the throttle body looked wet and really discolored. It had some sort of build-up on it.

So today I purchased replacement radiator coolant hoses a replacement hose for the lower throttle body line and the Lisle filler kit. Napa actually had one.



Does anybody have any pics of how they route their coolant line under the throttle body?

It is a very short 90 degree bend. So I purchase about 8 inches of coolant line and am thinking about making a large easy bend instead of a sharp turn.

WaLieN

I'd suggest just getting factory hoses, as they are pre-bent and will save you the hassle. Not to mention, it wont add more points of failure -- I think FDs already have their fair share of that.

Anyways, to answer your question:

In my case, it was an extreme situation. It all started when I was on the infamous I-405S during Friday LA rush hour traffic. Well, someone ran over the tread of a large truck tire, flinging it onto the underside of my car. Well, this basically just shattered the stock plastic endtank, draining all of my coolant all over the interstate. About a year and a half later, my coolant seal finally gave out after less than 20k on a rebuild.

The car was acting funny for a few days; it would puke some coolant once in a while. Then one day, it finally overheated from doing nothing. After that, the car would cold start really rough for about a minute, spewing white smoke everywhere.

In my case, the coolant seal was totally blown. I would be able to turn it by hand and have coolant spew out of the housing. I'd think YMMV depending on the severity of your blown seals.

Good luck with the rebuild.

jhammerrx7

iTrader: (5)

I got the radiator hoses and throttle body coolant lines replaced last night.

I found the thread about eliminating the throttle body line.

I just took the upper coolant line and connected it to the hard pipe going straight down underneath the throttle body. Then I removed the spring from the adjustment screw and tightened it all the way back down.

So I started filling the coolant (distilled water only) back up nice and easy.

I was supposed to get a bottle of water wetter in the mail yesterday but it didn't show up. Thats USPS for you.

I let it set for a while and then pulled the drain plug on my koyo.

Let it flush for a while and then filled it back up again.

The system has only taken about 3/4 of a gallon so far.

I pumped some coolant out of the overfill tank also until the dip stick was right at "F".

What is my next step? Start the car until the t-stat opens and then keep adding water?

Or is there another place I should add coolant?

I am just worried because when I remove the coolant line that used to go the the throttle body and pump the upper radiator hose I can't get any coolant coming out of it. I have the Lisle filler topped off with water, but the system seems like it won't take anymore coolant and it definately seems that when I flushed it I got more coolant out of it than I have put in so far.

WaLieN

I know this may sound stupidly simple, but try squeezing at the lower and upper radiator hoses. There may be really large pockets of air stuck in them, even if you used your Lisle filler.

jhammerrx7

iTrader: (5)

Thanks for the info.

Do I dare start the car up for a little bit if there is that much coolant missing?

jhammerrx7

iTrader: (5)

Here are some quick videos that I just took.

Sorry about the quality, they are from my camera.

I get tiny bubbles up to about 92 degrees C and then the coolant level in the funnel starts to rise and bubble like its boiling.

I'm pretty sure the t-stat opened and the coolant is circulating because I haven't added any anti-freeze since I drained the radiator and I am getting anti-freeze in the funnel. So at least the t-stat is working.

I can't find any leaks, but I think I'm screwed. The bubbles don't look good. I'm unsure whether they are air bubbles escaping from the system or if it is in fact exhaust.

One thing I did notice is that when you watch the top of the funnel you can see what looks like exhaust or steam. I can't really tell if its exhaust by the smell because of the coolant.

But anyway here are the videos.

And for the record, my car has idled like that since the rebuild. It needs a tune bad, but I think that is the least of my worries now.



http://s38.photobucket.com/albums/e1...t=103_0907.flv

jhammerrx7

iTrader: (5)

2nd


http://s38.photobucket.com/albums/e1...t=103_0908.flv

jhammerrx7

iTrader: (5)

3rd


http://s38.photobucket.com/albums/e1...103_0909-1.flv

jhammerrx7

iTrader: (5)

Let me know what you guys find from the videos.

Whats my next step if it is in fact the o-rings?

Drive it til its dead?

jhammerrx7

iTrader: (5)

Ttt

jhammerrx7

iTrader: (5)

Anybody???????????????