I am just finishing a restoration on a 1965 Mustang fastback which retains its original 289 engine. Supposebly the engine was rebuilt 12 years ago while the previous owner was trying to finish the car and sat with oil stabilizer in it up until I acquired the car. I have just about wrapped everything up but am having overheating issues that I believe are due to coolant sludge and rust deposits in the water ports. The reason I believe this to be the problem is due to the fact that the first time I drove this car it began overheating within 15 minutes so I pulled it over and popped the hood to find one of my freeze plugs leaking coolant immensly. I proceeded to trailer the car back to my shop and replaced the freeze plug. After I popped the old plug out I found tons of thick sludge and rust deposits formed behind where the freeze plug was. I took a screwdriver and dug as much out as I could reach, replaced the plug and took it for another drive only to find it overheated again. Is there a way to get all the sludge and rust deposits out of this engine? I took a garden hose and tried to flush it through the top radiator hose opening with the thermostat removed but I couldn't get any of the deposits to come out. Any advice?

 

I'd say about all you could do short of pulling the motor would be to remove the upper and lower radiator hoses and thermostat, probably the water pump too, and then try to flush out the block with high pressure water. Maybe it will force the crap out. It won't cost you anything but a gasket and maybe it will work. You should have the radiator boiled also if it seems plugged. Good luck.

 

Yeah, I was actually going to try that tonight. I really don't want to have to pull the engine but if it ends up being the only option I won't have much of a choice.

 

hey i did the same thing DONT forget u will need to flush your radiator u might need a new 0ne. that stuf gets in the cores and looks like the water is running good but you get a lot of the cores clogged up.

 

You need to take the car to a radiator shop. They can flush out the entire cooling system for you. You may still need a new radiator, but give that a shot first to get all of the crap out of the system.