head gasket? next step...

[stepper459]

So I have a 1972 F-100 with a 302 and 3spd manual. The radiator looked pretty bad and the temp would creep up when I let it idle for too long, so I replaced the radiator earlier this summer, and changed the coolant of course at the same time. I have been driving the truck a lot this summer and it's been running normal temps, although I noticed a slight drop in coolant level over time (only while running, no puddle under it while parked, as far as I can see in the dirt driveway). The last few times I've driven it, I noticed it running a bit hot, and I have had to add a lot of coolant. Like a gallon between tanks of gas. I put my hand behind the exhaust while running and it's noticeably wet almost instantly.
Does this sound like a blown head gasket?
Would it be a bad idea to drive it, even across town to somewhere I can pull the heads off and replace the gaskets?
And finally, if I do go about replacing the gaskets, I have read about proper bolt order and torques, but don't have a repair manual. Is there a good DIY thread on here? I did search but didn't find torque values or anything specific....

Sorry for the longwinded post... thanks in advance for the advice!

[robroy]

Good evening Stepper459!

While I can't answer all of your questions, I do have a copy of the 1972 Ford Truck Shop Manual.

From the 302 section, here are the instructions for removing the heads.

Page 21-21-11:





And here are the 1972 302 torque values.




Now that I've provided the sections you'll need from the manual, perhaps more experienced Dudes will provide some real-world advice.

Robroy

[stepper459]

robroy - thanks for the post, that's great information. One of the essential tools I don't have is a torque wrench (I have always borrowed one from work) so I ordered one. It looks a little more complicated than I was thinking, but nothing too terrible. The engine hasn't been overheated (just run a little hot) so I don't think I'll have to have the heads checked at a machine shop. Just a disassemble, clean, and reassemble. It will be good for the engine anyway, there's a lot of crap on it (grease, dirt, etc) and I just haven't cleaned it since all I've done with it is a tune-up, and it's been running great. Looks like a good rainy day project, so I can get this back on the road before it goes into the barn for the winter.

edit - of course, before tearing into this, I plan to do a pressure test on the cooling system as well as a compression test on all cylinders.

[fordman]

make sure to keep your push rods in the order they came out. and when putting the rocker arms back on tighten then down in a slow front to back squence. a little at a time and evenly. even if you have to do it slowly. but keep them evenly as you tighten them.

[cdeal28078]

Slow down a little here. Just because you get some moisture on your hand from the exhaust does not mean you have a bad head gasket. Moisture is also a by product of an internal combustion engine.
I admit that is a bit too much water to be loosing but check a few other things first. Like the water pump and radiator cap. A bad cap will let water pass going down the road and it will go out the hose (if you have one) and on the road.
I have had water pumps go bad and only leak while going down the road. They usually leave antifreeze under the truck somewhere if you look for it.
Pull your spark plugs and look for one or two that look like they have been pressure washed, very clean.
Any white looking exhaust while driving or idling? If it is much of a leak it will be white, have a sickly sweet smell.
Also a bad heater core will loose a lot of water. Sometimes they will leak under the floor mat inside the cab and you might not ever see the coolant unless you look for it.
clint

[stepper459]

Thanks for the responses... I'll certainly do some more investigating before tearing anything too far apart. Earlier when I got home from work I looked at the t-stat housing, where I have suspected a small leak... it's definitely leaking some, and when I pulled the larger radiator hose off the receiving pipe there looks very corroded. Additionally, the gasket behind that housing looks like crap and had been "fixed" with some liquid gasket compound or something that's squeezed out from behind it. So there's a place to start, anyway. I'll check the plugs, too. It's a little strange that I can't find a leak under the truck while it's stopped, but I don't have a great driveway for seeing those types of things. I might try to leave some cardboard under there tonight.

[stepper459]

So I replaced the thermostat housing, and of course the thermostat and related gasket while I was there, and so far so good. I checked all the plugs and they all look like they should, after a year or so of use. I'll have to keep checking the fluid level but it seems like with the condition of the old t-stat housing and gaskets behind it, I probably solved the coolant leak with that. I think it was pooling in the water pump housing, so I wasn't seeing a puddle, or at least not a noticeable one. Now that's all clean and unless the coolant level continues to drop, it's all better!

Thanks for the input, and thank god I don't have to do a head gasket (yet)!