UPDATE Dec 12/17 Took the heads to the machine shop - definitely head gasket issues so that was the problem. Kind of weird that the block test didnt show any combustion gases. I'll come back here when the engine is back in the car (have some firewall and other welding to take care of in the meantime).

UPDATED - See POST #8.

I bought this 1967 Delta 88 knowing that there is an overheating issue. It's sat in the garage for two weeks while I ordered the FSM and some other stuff.

During that time the radiator has pretty much emptied itself - and there is no coolant on the floor. I checked the oil dipstick and it's pure oil, so - I plan to take the plugs out today and I'm guessing that at least one cylinder will be full of coolant.

Any guesses on whether it's the intake gasket(s) or head gasket(s)?

Kind of weird because the car doesn't emit white smoke on starting or running.

Wish me luck.

 

maybe heater core ?

carpet wet on passenger side?

 

Check your transmission fluid.

 

Yes and no - that has leaked at some point and it is currently bypassed, the heater hose from the water pump is connected directly to the valve at the back of the engine.

 

Oh that's interesting. Leaky core plug at the back of the engine?

 

No, it would be a leaking transmission cooler coil in the radiator. Your transmission fluid will show really high on the dipstick.

 

Got it. I'll check that too.

 

Well - I checked everywhere and I couldnt find the missing coolant. Nothing in the oil, nothing in the tranny. I removed all the spark plugs and turned the engine over, nothing. I figured it as an air pocket or something, so I decided nevertheless to run a block test.

BTW this is the first time I've allowed the car to get up to temperature.

I ran the test 3 times. First - with the coolant 2" below the top of the radiator and cap off. Engine warmed up, I started pulling the vapors thru the blue fluid but the coolant was rising in the radiator so it interfered with the test tube. I removed the tube and shut her down. Test 1 - 20 seconds but fluid stayed deep blue.

So - test two. I drained a little coolant to about half full on the radiator, cap off. Started her up again, and as the coolant started to slowly rise I ran the block test for about 1 minute. Then WHOA the whole thing puked up about 2 quarts of hot (ish) coolant straight out the top of the radiator. Caught me by surprise. Test 2 - fluid stayed deep blue.

Test three. When things were cooled down a bit I installed an (empty) coolant expansion tank, with the radiator expansion pipe hooked to the base. I figured it would be safer and I could monitor the amount of coolant actually expanding under normal conditions (i.e. with the cap on). The radiator was full. Started her up - ran for about 5-7 minutes with no fluid going into the expansion tank. Eventually I started seeing fluid coming into the tank, and I was able to get a good block test. Then - WHOA (again) - the expansion tank filled up quickly, I shut the lid and I lost about a quart out the expansion overflow. Test 3 - fluid stayed deep blue, total coolant expanded out about 2 quarts.

Observations.

1. With the radiator cap on, engine running, before the thermostat opens, the top hose is cold but shows it is holding a lot of pressure
2. After everything puked out on test 3, the radiator was only hot on the passenger side, the drivers side was basically cold.

So - I think the coolant is boiling in the block and there isn't any real flow through the radiator. Either the thermostat is dead (I'll test it next or run without it for a test), or the waterpump isnt working properly (I'll remove it and check it next), the radiator sucks (it's new but under sized.. irrelevant for this test but needs to be checked anyway)... or the block has some blocked passages (worst case). At this point I'm pretty convinced the head gaskets are good but I plan to do a compression test as well.

Hopefully this explains what's going on, I'd be happy to hear opinions, I'll post the next update probably next weekend.

Back on Delta (airlines) tomorrow.

 

Sounds like your thermostat is sticking/stuck closed.

 

Quick update - here's what I found.

1. Someone had already removed the thermostat
2. The radiator had no gunk in it and it was flowing freely both directions using a hosepipe.
3. The water pump is in great shape, the impeller is tight on the shaft. Some minor reddish residue on the inside of the water pump. Maybe some history of block seal or the trans cooler is leaking (but I didnt see any evidence of either in the coolant)
4. When I poured water in the thermostat opening it flowed freely (and cleanly) out the front of the block (both sides)
5. When I used a hosepipe (with a rubber seal) to put water in the front of the block it flowed nice and clean out the top. Same for each bank.

So - compression test tomorrow. At this point I'm leaning back to head gasket, it's the only explanation for air pockets and boiling over, although puzzling that the block test was negative.

 

kinda going through same problem with a 455. If coolant level is 3/4 full ok. If any more it'll puke. Also smells allitle funky out of exhaust...but idk if it's just this new gas...dosnt loose coolant and will run at a normal temp
verified buy another gage

 

If your using a stock radiator there is mark on the rear passenger side. Usually about an inch over the trans cooler. If radiators are over filled it leaves little room for the water to expand when hot and will muscle past the radiator cap seal and puke.