[Skippy4773]

I recently flushed the radiator and put in prestone radiator flush solution with distilled water. It ran fine while I ran it with the distilled water and radiator flush but after I drained that and replaced it with prestone 50/50 it overheats very quickly just standing still from a cold start. Any idea what this could be?

[NMKawierider]

I recently flushed the radiator and put in prestone radiator flush solution with distilled water. It ran fine while I ran it with the distilled water and radiator flush but after I drained that and replaced it with prestone 50/50 it overheats very quickly just standing still from a cold start. Any idea what this could be?

A couple of things come to mind. One- I hope you didn't run the flush for very long and if so...sometimes it has an effect on the thermostat and/or the pump impeller.  The other thing is these engines trap air...especially in the pumps and that stops flow. Might check that out.

[Skippy4773]

I ran it idling for about 30 minutes. How would I find out if air was trapped in the pump and correct it?

[NMKawierider]

I ran it idling for about 30 minutes. How would I find out if air was trapped in the pump and correct it?

Pull the hood, remove the radiator cap. Jack the front up at least 8"s more if possible. Then reach in on the driver's side and squeeze both the radiator hoses a few times. Then start it while cap off and jacked-up. Let it run above idle..say 1800-2000. Watch the coolant in the radiator. It should just barely be moving while cold but when the thermostat starts opening it will increase. If it overheats before this happens, and you do see movement, lt's likely the thermostat is stuck and will need replaced. If the coolant starts moving faster and it gets hot to the touch, make sure the level is about 1" down from the top at this point. Then in a few minutes the fan should come on. If it doesn't and it overheats, there is a problem with that fan system. Probably the relay or the fan motor or it's fuse. If the fan does kick on finish filling the radiator to the very top and install the cap....and let it down. Try it out. We may have worked-out any trapped air by jacking it up. 

[Skippy4773]

Thank you. Was just strange how fast it overheated from a cold start. The fan is currently working I can hear it kicking on. Assuming there is air stuck in the lines.

[doug80638]

Look for bleed screws on top of the thermostat housings for releasing trapped air.

[Skippy4773]

Look for bleed screws on top of the thermostat housings for releasing trapped air.

Are they above the drain plug?

[NMKawierider]

Look for bleed screws on top of the thermostat housings for releasing trapped air.

Are they above the drain plug?

Right in the center of the caps on both cylinders. These bleed the air off the top end of each cylinder when changing the coolant.

[Skippy4773]

Should I bleed them while the engine is running or off?

Look for bleed screws on top of the thermostat housings for releasing trapped air.

Are they above the drain plug?

Right in the center of the caps on both cylinders. These bleed the air off the top end of each cylinder when changing the coolant.

[Skippy4773]

NMKawierider I'm sorry I think I messed up on responding. Should I open those two bleeder valves on the cylinder while the engine is running or while the engine is off? And do you happen to have a picture of exactly which screws I'm not sure which ones they are. Thank you.

[NMKawierider]

NMKawierider I'm sorry I think I messed up on responding. Should I open those two bleeder valves on the cylinder while the engine is running or while the engine is off? And do you happen to have a picture of exactly which screws I'm not sure which ones they are. Thank you.

Never open those when running or full. The procedure is: when draining they can be open when the level is low enough not to allow coolant to come out...just air in.But when re-filling, the lower drains are closed while the air bleeds are open as you fill it through the "raised" radiator until coolant starts to come out the holes. Then install the screws, then continue filling until the radiator is almost full. Run and keep coolant about 1 inch below the neck until the thermostat opens and the fan kicks on. Then fill to the top so there is no air gap, reinstall the radiator cap, and let it down. 

The air bleeds are on top of the two housings-one each for each cylinder. Looks like this-#20.

[gchesterton]

Thank you. Was just strange how fast it overheated from a cold start. The fan is currently working I can hear it kicking on. Assuming there is air stuck in the lines.

There are burp screws on the water inlets on the top of the motor as well.