Overheating... Tipo head

[johnnymack_mk1]

Hi all,
Mk1 Punto racing Car with the following overheating problem...

Mk1 tipo head sitting on a punto block. After 10 mins of running, the temperature moves reasonably quickly to 90-100 degrees. Its not loosing any water at all and has no thermosat fitted. The water pump and cooling system are all in perfect working order. We just cannot figure out why its overheating and not loosing any water.

We pulled off the head to check for a a weeping head gasket. The gasket and head both look spot on with no problems.

On the top of piston 1 & 3 there is slight shining on the top right of each piston and it just looks out of the ordinary...


Anyone any ideas??

[Guy Croft]

Can't see a thing in those giant blurry photos, take some decent ones please.

G

[johnnymack_mk1]

Photos resized...

[Guy Croft]

TIP: I need high defintion shots to analyse things like this, not just resized.

Anyhow I can see a bit better, thanks.

I venture to suggest that since the head gasket is apparently OK your ignition timing is retarded? That can cause serious and fast overheating. Too lean can do that as can high ex system backpressure.

Your comments please.

G

[Rich Ellingham]

Johnny, put the camera on Macro mode (usually a picute of a flower on the setting) kill the flash and use external light source, good photos of the fire rings are useful.
Something like this


Did the car overheat with the thermostat in place before?

rich

[tricky]

Have your head pressure tested, I have had a fault with the exact same symptoms recently on a punto GT. It turned out to be a cracked head. Does the engine only become overheated quickly when driven , and not on idle ?