BHG?

[gixxer750]

Well, I have blown two radiator hoses off now. One(top) was the original hose. I have no clue why I reused it. It swole to about 2.5 inch diamater and began to leak around the stock spring clamp on the thermostat housing. OK, so I replaced that hose three days ago, and used worm gear clamps on it. Its fine.

The bottom hose popped off today. It slid right off of the koyo radiator. It was a new hose, but using the original spring clamp. The hose was unhurt. This happened after I cut the car off. I was walking to the house, and got on the porch when I heard it pop and saw steam go everywhere.

I did a compression and leakdown, and both reveal everything to be in good working order. I am not losing water normally, and there is no water in the oil or combustion chambers. The coolant resivoir does not get low, and I have a 16 psi TRD radiator cap.

The head gasket is a cometic 2.0 mm 590 miles. ARP head studs where used with ARP moly lube, and where retorqued at 500 miles. Torque is 85 ft/lbs. When the engine was put together the block and head where both surfaced to the correct finish. Both head a block are true and straight.


Is this just a freak thing, or should I be worried.

 

[IJ.]

I'd be worried Gixx

 

[Reign_Maker]

I dont think I would be worried about a BHG, but you might have some obstruction in your radiator, OR, your thermostat might be closing too soon... Check the easy things before worrying about the hard things...

 

[gixxer750]

I am.... what to do? I did a leakdown and a comp test, both turned out great.

I forgot to mention 1 thing. No antifreeze yet. Maybe the coolant was boiling building pressure after I killed the car. I have checked the overflow and the water is cool in it after a run, and the rad cap is working. So that means that it is not building over 16 psi in the cooling system....

 

[gixxer750]

brand new thermostat, and a 4 month old koyo race radiator.... It was cleaned and flushed before putting it back in. The thermostat is a 180 degree toyota unit. I clipped the bypass thing off and drilled the hole out, and also put if facing the top. The temps in the car never exceed 195 deg F.

 

[gixxer750]

and oh yes.... this engine had not yet seen over 2.5 psi of boost.

 

[Reign_Maker]

use better clamps? And still, CHECK your thermostat... Just because its "new" doesnt mean it wont fail... Same thing with your radiator... The other thing I would suggest, go to a radiator shop and see what they say... A professional rad guy might shine a better light on it... We're just so prone to jump on the BHG band wagon, but I do NOT think you have a bhg from what you said... I refuse to believe 2.5psi, ARPs and Cometic are gunna blow that easily...

 

[IJ.]

Heat soak sitting shutoff and yep you got it no coolant = Boiled!

 

[Joel W.]

Sounds like the radiator cap may not be venting?

What is the name of the "kit" that checks for exhaust gasses in the coolant?? Not saying that's it. just wondering as I want one..

A good way to see if the radiator is flowing properly is running your hand across the face feeling for cold spots. Should be even through out.. Not saying thats it either..

 

[gixxer750]

Block tester.... I guess I'll go to napa and get one. I'll check my thermostat tomorrow. I'm getting good stainless worm gear clamps and antifreeze tomorrow. Then we'll see.

 

[Reign_Maker]

Werd, like Mix Master Joel says: rad cap! Check that too... It might not be letting the over flow bottle do its job...

 

[Joel W.]

I was thinking since you used a Koyo radiator, you might want to see if their's takes a special Koyo radiator cap? Not sure if they are different..

http://www.speedtechnique.com/koyo-skc13-hyper-radiator-13kgcm2-p-19643.html

*Note: Use with Koyo OE replacement radiators with micro cap filler neck

Hmmm...

 

[gixxer750]

It's always worked fine before, and the instructions I got with the radiator say that you can use your oem cap...

 

[Joel W.]

It was a long shot.. It still might be worth while to try a different cap..

Hope you figure it out..

 

[gixxer750]

I'll figure it out one way or another.... I just hope its not the pull the engine way.

 

[3p141592654]

There are two OEM rad caps. You will need to measure the rad neck depth to the land and your cap sealing ring depth to make sure everything fits okay.

 

[MDCmotorsports]

When doing the leak down test, fill the radiator up fill. Fill your over flow bottle, full.

Pressurize the system. If you see the level of water in the rad or the over flow bottle rise, you have bhg.

 

[Nick M]

The bottom hose popped off today. It slid right off of the koyo radiator. It was a new hose, but using the original spring clamp.

Technically, you are not supposed to reuse that clamp. It should be replaced. But yes, I have reused them with success.

 

[IJ.]

Gixx: Not sure if it's the same with the Koyo but the PWR rad has smaller outlets than stock?

 

[gixxer750]

I found the problem. I feel stupid.

Apparently, in the 3.5 months the car was sitting, a dirtdobber has decided to build a nest in the hose that goes to the overflow. So, the radiator cap was venting it's little heart out, but the coolant had nowhere to go when I cut the car off causing a pressure spike.

Thanks for the help guys, but no one ever would have guessed that one, and I found it by accident.