mustang 71

Own a mustang 71 which is a classic, but I have this problem since I bought it. It tends to be at high rpm on the highway and when I get home it throws up the coolant. It is usually running at high rpm. any suggestion will be appreciated.:banghead:

Gonna be near impossible to diagnose with such a brief description of the situation.

What do you consider high rpms?
Is the car stock?
Built motor? Tranny?
Done anything to the cooling system?

It's not unusual for latent heat to cause a surge in the cooling system when the engine is shut off. In olden times, cars didn't always have overflow tanks. Install one, and use a modern radiator cap. It will puke the coolant into the tank and siphon it back as it cools. No biggie!

Jim

thank you for your reply's, but the problem is that when I get in the Highway the RPm are higher than what they should. It has a manual transmission. I change for a bigger radiator but no luck, after I get back home starts throwing up the coolant. I bought it in Ohio, it is stock with a cleveland motor. I have always thing that my transverse is making rpm go that high. It just seems that the higher MPH I go the higher rpm it gets. the thermostat does not show really over heat it is at middle reading. any feedback will appreciated. thanks

Well, rpms are supposed to go up with the mph. I dont know what gear came stock in '71 but if you want to lower rpms on the highway consider lowering the rear gear (numerically). Or install an overdrive transmission.

You might have a blown head gasket . Check the compression.