Yes, it's new to me - I bought it from a guy on bring a trailer only 100 miles ago. Word to the wise.

I believe I have seen some flow, but not sure how powerful it is or should be. Seller had a receipt for recently having had the heater core flushed, but not the radiator.

I just want to be sure properly troubleshoot this, because the shop is happy to just go ahead and do the head gasket, naturally.

 

Usually not one to just throw parts at a problem but what I'm about to suggest is what I'd replace when doing a HG job if you don't know the history on each part. Go ahead and get new hoses, inline t-stat, new water pump and new radiator. Those aren't a huge sum of money and should be doable to install in a day even being unfamiliar with the vehicle. You then will have a solid baseline on the cooling system and be able to further diagnose your issues and be set up for the future whatever that may hold.

 

@desmorider My bet is it had a head gasket leak and the previous owner tried a bunch of stop leak. That ends up gumming up the entire system and you get overheating

 

Factory 180 is worthless, throw it away asap. I have two brand new you can have for free (you pay shipping).

You know you have a blown hg, ok, not the end of world. If you need/want to drive it you need to run it with no thermostat installed. Easy to do with the inline kit and no element, otherwise you can connect the top radiator hose directly to the manifold outlet pipe (it will have a weird kink in it but will work). Autozone sells a hose repair kit with a plastic splice similar to the metal splice I put in the kit, put it in place of the thermostat.

Idles all day without getting hot, gets hot on the road? Classic plugged radiator. Check the radiator to make both sides are hot, check lower rad hose too. If those are not hot, you have a plugged radiator.

 

Also, I have driven trucks for months with blown hg, have a buddy whose truck has been like that a year (drives it very little). I had one that hydro locked in the driveway overnight, tried to start it and would not spin over. Luckily no damage, pulled the spark plug, turned it over by hand to empty the cylinder, started it and drove it in to shop.

 

I had this on an '88 Dodge I bought.

With exhaust gasses in the coolant, you know there's an issue whether I be head gasket (hopefully, most likely), a cracked block, or a cracked head. If it were me, I wouldn't spend a dime other than an inline thermostat kit, oil pump, and a cheapo head gasket kit. For any of these issues, you're tearing the motor apart. I would be pulling the heads first thing. Look at the head gaskets that come out and see if you can tell where they've been leaking.

Second, while the heads are off, look for signs of Stop Leak in the motor. Pop a couple freeze plugs out and look inside the coolant passages. Run a (good) pipe cleaner in and see what comes out. *If* you find signs of "head gasket in a can", pop all the freeze plugs out and go to town with the pipe cleaner/brake clean. Get all that crap out you can. That is, unless you want to save the time and just find a used motor. Likely what I would do if you can find one locally, reasonably.

Now, another contingency here is cam bearings. Once one of these Rover V8s has been overheated in the 230-240* range a couple times, the cam bearings (particularly #3) are really bad for walking out of their bores. While I had the engine open, I would be hard pressed not to replace 1 thru 4 cam bearings. You can't replace #5 without pulling the motor, but #5 should be fine. Also oil pump while you've got the timing cover off.

Now! If you decide this is a lot for the motor in the truck, or if you find another critical issue, I would just grab a used motor. Before it's installed, go ahead and do the head gaskets and oil pump. Throw that motor in and go happily along your way.

Whatever you do, just check for stop leak in the current motor. If you find any, go ahead and replace the radiator as well. If you don't find any, I wouldn't replace the radiator.