Hi a bit of advice needed if you don't mind , I put a fully forged 2.5 block with cosworth gaskets in about 20.0000 miles ago the car over heated water was spilling out the bottom of the radiator and when I opened the header tank coolant spewed out the top. Strange thing is on idle he car can sit ok and not over heat but as soon as the wheels are in motion instant overheat, all advice is appreciated .


Kenny

 

Have you a leak in your radiator (from what you say, you have)?

 

What does the oil look like Kenny? Any mayo in it?

Is there any in the coolant?

Any white residue on the exhaust pipes or a sweet smell?

I think you need to rule out HG failure or a leak (crack) from cylinder heads etc.

Hope it is something easy to fix!

 

Sounds like the system is pressurising from a cracked head gasket. sitting under no load the pressure will be much smaller in the cylinders. When the car is driven the engine is under load, causeing one of the pipes to expand and leak. Hold the bottom hose and get someone to rev the engine to boost and you will feel the pipes expanding. If you did a test you will find hydrocarbons in your water. Mine did the same thing. I had no water or oil mixture either

 

Subaru's with head gasket issues generally dont mix oil in water or vice-versa due to their layout...........

 

Thanks for the replies guys , turns out a few issues but main one being cracked radiator hose , getting sorted as we speak .


Kenny

 

You'll be glad it's not the engine.

 

It would have been a little unusual for it to go again after forging it!