I'm assuming head gasket, cracked block or head???

[tweety]

'79 midget 1500 ZS Carb.

Sunday, the car overheated and just about started to boil over. Close enough to home that I made it (about 3/4 mile.)

Car cooled off, I refilled the coolant (it was about 25% full)Now the car seems to be ok until it warms up, then it looses power and misses/sputters under load between 2000-3000 RPM. I have not driven it long enough to see if it over heats or boils over.

Seems to me like a cracked block or head due to the severity of the missing/sputtering but could also be just the head gasket?

Yes, the oil cap had a little bit o milk shake on it when I checked but not as bad as I expected to see. Doesn't seem to be water/steam out of the tail pipe.

Does this repair requite pulling the engine or can it be done in the car?

 

[Midget78]

Sounds like your gasket may be just slightly blown. On the 1500 you can remove the head with the engine still in the car yet it doesnt make for the most comfortable working experience. There is some other posts on here as of late that discuss the right brand of gasket to purchase as well as a spray on adhesive that will help seat and seal the new gasket for miles to come.

 

[regularman]

Sounds like a head gasket, lets hope that is all it is.

 

[twas_brillig]

Depending on budget (and if you have an air compressor), you might want to buy/borrow a leak down tester - I picked up one a few months back for about a hundred bucks Canadian to try to figure out if I had engine problems or not.
Put the piston at top dead centre; screw the thing into the spark plug hole; pressure the combustion chamber up with your air compressor (you don't need a lot of volume, just decent pressure) and then see how slowly/quickly the pressure drops and if there's any signs of leakage past the carbs, out the exhaust, or into the coolant system. I wrapped saran stretch wrap over the carb inlets and the exhaust pipe and rad filler to look for pressure leaks there.

The above comments are from my failing memory of my one experience; I can have a look at the instructions that came with it if you're interested.
Doug

 

[Midget78]

Check your local auto store(s) for equipment as such to rent. Usually they will say you need a deposit of $50 or so (to cover the equipment if you split with it) but give it right back to you upon returning the equipment. I know a compression check will give you some ideas what is going on as well.