Hi guys, I've been having the following problem on my turbocharged D16A1 for the past two months...

The system will 'geyseur' coolant out from the radiator cap at random. There is no warning. Obviously, there is a surplus of pressure and the cap is relieving it.

Here's the deal:
Two new radiator caps
Two new thermostats
Bled system multiple times
System pressure check = fine (steady, 13psi via pressure checker [engine off])
Replaced upper radiator hose
Coolant looks fine
Oil is not milky
Idle is perfect
Performance is perfect
System never overheats

It seems to me that the only thing left is the headgasket. I've had a blown head gasket before and it had all the symptoms such as rough idle, smoke, milky oil, etc.... this engine is showing none of these signs.

The only things making me think "headgasket" is the cause are:
1. High pressure immediately following startup.
2. I've replaced everything else already?

I'll try a compression test this weekend.

Any ideas?


Modified by redteg_87 at 1:49 PM 3/3/2004

 

Forgot to mention...

Head gasket and water pump were replaced ~20k miles ago and there have been NO problems with the cooling system in those six years until these past two months.

 

How old is your radiator ?

 

It is the stock radiator. So 16 years old. I rented a cooling system pressure tester from Autozone to check it. With the engine off and the system full of coolant, I pumped ~14psi into it. The guage read steady the whole time. Wouldn't a clogged radiator have the pressure decrease as the blockage is averted?

 

bump for the afternoon crew

 

Biddy-iddy BUMP... for the night crew.

Any ideas before I swap head gaskets...?

 

Help?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by redteg_87 &raquo;</TD></TR><TR><TD CLASS="quote">

Any ideas before I swap head gaskets...? </TD></TR></TABLE>
A leakdown test will would be a good idea. No need to swap a headgasket without being sure it's bad.

 

To check the Cooling System for a Head Gasket problem, I would first, with the engine cold/warm, remove the Radiator Cap. Next I'd have someone start engine while I watch the opening in the Radiator. If Coolant surges out of it, your chances are good that you've got a Blown Head Gasket. Coolant surges out because of the high combustion pressures. Thus a Blown Head Gasket would allow pressure to come out of the Cylidner and through a Cooling Passage causing a surge..

As for the Radiator, 16 years, I'd toss it. But if it looks fine on the outside I'd perform a Flow Test on it before tossing it.. To do a Flow Test, just disconnect the Upper and Lower Hoses and run water through the Radtiator. With a high flow of water entering the Radiator, there should be a high flow of water running out of the Radiator. If the flow is restricted, just get a new Radiator..

Good Luck..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chiovnidca &raquo;</TD></TR><TR><TD CLASS="quote">
A leakdown test will would be a good idea. No need to swap a headgasket without being sure it's bad.</TD></TR></TABLE>
Yeah, I'm going to try one today.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PnX-R &raquo;</TD></TR><TR><TD CLASS="quote">To check the Cooling System for a Head Gasket problem, I would first, with the engine cold/warm, remove the Radiator Cap. Next I'd have someone start engine while I watch the opening in the Radiator. If Coolant surges out of it, your chances are good that you've got a Blown Head Gasket. Coolant surges out because of the high combustion pressures. Thus a Blown Head Gasket would allow pressure to come out of the Cylidner and through a Cooling Passage causing a surge..</TD></TR></TABLE>
It definately has high pressure immediately upon startup.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PnX-R &raquo;</TD></TR><TR><TD CLASS="quote">As for the Radiator, 16 years, I'd toss it. But if it looks fine on the outside I'd perform a Flow Test on it before tossing it.. To do a Flow Test, just disconnect the Upper and Lower Hoses and run water through the Radtiator. With a high flow of water entering the Radiator, there should be a high flow of water running out of the Radiator. If the flow is restricted, just get a new Radiator..

Good Luck.. </TD></TR></TABLE>
I ran a pressure test and it held a steady 14 'pumped' psi of pressure. The pressure didn't slowly fall off as if there was a clog. Oh well, I'm going to use a new radiator anyways in a few months, here.

Thanks for the replies, guys.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by redteg_87 &raquo;</TD></TR><TR><TD CLASS="quote">
It definately has high pressure immediately upon startup.


I ran a pressure test and it held a steady 14 'pumped' psi of pressure. The pressure didn't slowly fall off as if there was a clog. Oh well, I'm going to use a new radiator anyways in a few months, here.

Thanks for the replies, guys. </TD></TR></TABLE>

Told ya it was the radiator ...

Prolly one of your ****** lodged in there ...

huh ...ryan ...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tsunami_zc &raquo;</TD></TR><TR><TD CLASS="quote">

Told ya it was the radiator ...

Prolly one of your ****** lodged in there ...

huh ...ryan ... </TD></TR></TABLE>I pulled the ***** out a month ago... but the problem remained.

Good one, Steve.

 

Ran a compression test just now:

1..........2..........3..........4

160......160......155.....165

No loss in compression. I drained the reserve down to just under the "MAX" mark. I made it home no problems... perhaps something that simple could have been the cause?

 

Hmph...

I am no longer blowing coolant out through the radiator cap, but the coolant reservoir is taking on that great overflow of coolant. I suppose the problem must remain.

 

i have the same problem

 

hmm.. I don't get it.. Could you explain??

 

Theres actually a combustion leak tester you can buy to test for combustion vapors in the cooling system. Its like a little glass tube with a blue liquid in it and a pump on top. You put it in the top of the radiator and pump it to take in air. If combustion vapors are getting in the cooling system it will change the color of the liquid to green. Snap on sells it but i dont have my cataloge its at work in my tool box. Im sure you could get it cheaper through someone else anyway!~

 

To be exact i believe it detects carbon dioxide ( 1 of the by products of combustion) because you can breathe on it and pump it a few times and it will turn color.

 

I've been told about these testers (apparently there are strips, too) but I can't find them locally.

I'm swapping out the radiator next week. I'll let you all know if that fixes the problem.