Hi Guys Attended a rod meeting yesterday. This required a round trip of 450 miles (give og take a few). I ran it at 75 mph both ways, with no issues, until 30 miles from home. Suddenly i noticed that the needle on the thermometer was gone, it was out of the scale . I was just overtaking a couple of trucks, so I lifted and falled behind, put it i neutral, killed the engine and coasted to a halt. Everything seemed fine, it feelt normally hot, no boiling. Only fault seemed to be the thermometer, poked the glass a little and decided that it was toast. Cranked it up and stood on it again. 10 miles later I got this whiff of hot engine, killed it and coasted to a halt. Man it was HOT , puke pipe looked as a steamcleaner and smoke from the oil fillercap and breather pipe. Grabbed an oilcannister and poured 2 pints of oil into it. Cranked it and let it idle 10 - 15 seconds, stopped a minute, idle again 10 - 20 seconds. Did this 8 - 10 times to cool the bearings. When cold I filled the radiator with a little more than a gallon of water . Let it idle till I burned my fingers on the waterneck, refilled and took of Again. Ran it a mile or 2 and checked again, it took a pint more water. Found a piece of hose and stuck it on the puke pipe and tied it to the headlight stand so I could see it while driving. Ran it at 50mph, it puked a little, but stopped again, ran a couple of more miles and checked the level, which was perfect. Stepped a little on it, and shure enough, it started boiling. Let of the gas, stopped and everything was perfect, could even lift the fillercap without problems (pressurized radiator) Scratched my head again, and decided that the thermostat was sticking or partially blocked. Ran it the rest of the way home at 50 mph no problems at all. Today I pulled the thermostat, and cooked it on the stove, it opened as it should at 75 Celsius, and opened fully. No signs of crud or rustflakes anywhere i housing or cylinderhead. I'll run it the next couple of days without thermostat and se what happens. By the way: No bubbles in the water, and pump is working fine, so I rule out headgasket and faulty pump. Any comments???? What have I overlooked Never had problems with it before, so I'm still leaning towards sticking / clogged thermostat. Engine in question is a 60 hp Volvo four, pulling this:
@ Blowby: Nothing :-( ,I can se through radiator when driving @ adjustablejohnsons: Thats an idea, will check it out. They're about a year old, but you never know about crap from China
Many bottom radiator hoses used to have a coil spring in them to prevent collapsing. Think that has gone the way of cheaper manufacturing.
Sounds like my banger in my coupe. 35-40 it's peachy. 45 or try to climb a hill, bye bye water. My head gasket isn't sealing all the way because of a crack on the deck surface. When under load, it leaks enough compression into the cooling system to form a super heated pocket of coolent. When that pocket gets big and moves, it boils over Posted using the Full Custom H.A.M.B. App!
You gotta pressurize system cold with it full of water and see where it leaks. Remove spark plugs and let the thing sit under pressure for awhile. Pump it to what the cap releases at. If no gushers visible then let the thing set under pressure for an hour or two. Then crank it with plugs out and see if you have coolant in the combustion chambers. Watch out, they'll shoot 30 feet! If you don't have a cooling system pressure tool it's time to buy one. Finally, what coolant mix are you running? I can't imagine a radiator air flow problem with that radiator going down the road. Interally, who knows?
Replace thermostat they are cheap, but colapsing hose also sounds likely. Still have issues do a check for combustion gas in cooling system. Also make sure your distributor advance is getting full advance.
Hi guys. Some times simple things gets tricky. Checked - rechecked and checked for combustion gases. No luck. Took it apart and found a intact headgasket BUT it was black between cylinder 2 and 3. There also 2 big channels for coolingwater in the same area. Seems that 3 studs were not thightened in the block, when the engine was rebuilt som twenty years ago. So I threw in a new gasket and buttoned it up again Oh by the way! Always remember to drill a small hole in your new thermostat. Especially if your engine runs without a by pass for cooling the head ;-)
I've kept the springs out of old lower hoses just for that purpose...putting them into new hoses. I'd also check your cap. If the cap isn't maintaining pressure the cooling system will overheat.
It is a long shot but I had it happen years ago. Drove me crazy trying to solve the problem. Turned out to be a busted vacuum advance diaphragm in the distributer. Finally found it when I noticed a fluctuation of power while driving at a constant speed (the advance was moving back and forth). Charlie Stephens
I am with smog guy.... Get a hand held pump, pump up the system, and check for psi loss.... Hows the oil look? Nuthin out the exhaust? Feel the bottom hose, there should be a spring in there. If not, get one and put it in....
The Jalopy Journal
