Hey there. I recently acquired a 1973 ford f350 with a 360. I got this from my parents, it was used once a year as their camper hauler, and it has had overheating issues for a long time. It blew a radiator about five years ago, and last year blew the thermostat housing. A few weeks ago, I was driving on a hot day heavily loaded, and steam blew from under the radiator cap. When I thought it was cooled off (about 15 minutes), I opened the cap to pour water in, and even more steam came out. I lost a total of 3 gallons of coolant. So I took it to a radiator shop for a diagnosis. They did a coolant pressure test and determined my coolant system doesn't leak, and did a hydrocarbon test, and they said that it pointed to a blown head gasket. I have not picked up my truck yet, I will update when I have, and have more specifics. Anyways, is this definitely a busted head gasket? I do not have oil in my coolant or coolant in my oil. I can't afford to pay someone to fix it, and I am a novice wrench. I am not totally opposed to doing the job myself, as long as it isn't going to tie me up for weeks. Approximately how many hours does this job take? Is it necessary to get my heads machined? I'm assuming it's had this HG leak for a while, if that's been the problem the whole time. Would it be inadvisable to drive it a couple hundred miles before tearing it apart? This is my only running vehicle.

 

If they pumped it up it should have leaked the psi off if a gasket is leaking. They told you it does hold psi ? I don't see how they can tell you it doesn't leak but your head gasket is leaking. Could be a head gasket, then again may be just the cap is bad.

 

I would believe that the cap is bad. But would that account for the hydrocarbons in the coolant? A friend told me it might be rings or valve seals.

 

You can't really drive it like that. Find something else to drive while a good diagnosis and repairs are made.

 

The "overheating for years" part needs addressed as a minimum. Overheating is hard on the engine... especially cylinder heads and head gasket seal.

Most likely the original radiator is plugged up. Can you inspect or have a radiator shop inspect? It could be other things also. Assuming it is the radiator, a thorough flush and new radiator and thermostat should clear that problem up. There are lots of posts on radiator choices and flushing. A Champion radiator has worked well in my '78.

The head gasket change is doable in an afternoon by an experienced mechanic but it is tricky to do successfully in chassis on a seasoned engine. Not a good "1'st project" IMO. Also the head could be warped by time and overheating which would require machining.

 

The radiator, thermostat housing, and thermostat have been replaced in the last 5 years. This would not be my first project, I have done smaller things like rebuild carbs before, but I've mostly worked on motorcycles.

 

Check compression. Piston rings lose their tension after overheating.

 

OK... I wonder why it is heating up then with fairly recent cooling system service? Perhaps an issue re occured or coolant passages in the block are heavily gunked up.

As far as the head gasket, get a good service manual, take lots of pictures of wire/hose/linkage routing and go for it.

I think you need to get the "heating up" part diagnosed and fixed first though to have a dependable truck. It sounds from your post like it is a long term problem.

 

Well, my truck came back from the shop. They said the hydrocarbons in my coolant were at 500ppm, which they characterized as "the head gasket is very close to catastrophic failure". Is this the truth? My truck was running with the temp needle between 1/2 and 2/3 to the "H" most of the way home peaking at 3/4 for about a minute. The needle rose when in motion below 40mph. When I was idling, driving faster, or in the shade it would run at 1/2. I've resolved not to drive it for now.

 

Why do you think they are lying?

 

My mechanic friend questioned it, and claimed that it could be caused by other things like valves or rings etc. Don't get me wrong, I trust the shop more. I trust, but I verify.

 

The use of the vehicle should be minimized until the problem can be resolved. Overheating an engine is not a good policy. A warped or cracked head or block would require machine shop work. A blown head gasket can cause overheating without fluid exchanges. If you decide to do the work yourself, and you are inexperienced, first get a service manual which covers that engine. Read and understand it thoroughly. Try not to guess what the problem is. Get a comprehensive diagnosis before doing the repairs.

 

I ordered a service manual on CD, a leakdown tester, and a compression tester, so I should be set to diagnose and repair when my college classes get out. I have a full set of basic hand tools, and access to an air compressor and torque wrench. Are there any other things I need for this job?

 

I think you have it pretty well covered. That, a single edge razor for removing gaskets and a "head set" which is the complete set of gaskets needed for a head R&R available from your local AP store.

 

Has the water pump been replaced? You said the truck was used once a year for camping. Sitting for long periods can cause corrosion which will effect the flow. I would start there check the compression and do the leak down test yourself.