Bleeding the cooling system

[mluder]

I couple of weeks ago my car overheated and a lot of coolant boiled out o the overflow. I need to refill the system and start looking for leaks but I'm not sure what the pro refute is for bleeding it. The workshop manual refers to section S for instructions but the manual I got from DMC stops at section R. Is there a section S?

Is there instructions anywhere on how to do this bleed? I know that you need to open somewhere at the radiator as well as the engine but where? What's the best method? I'm losing summer months and want to get my car back out on the road.

Thanks.

[Ozzie]

If you don't have a self bleeder, the coolant bleeder is on the cap of the coolant pump.
The other location is the top hose that goes into the passenger side of the radiator.

A while ago I documented a procedure here ("Burping your new DeLorean baby") (http://delorean2109.blogspot.com/2008/08/burping-your-new-delorean-baby.html), along with a discussion and pictures of how to simplify the task with some aftermarket bleeder kits.

[mluder]

Thanks, Ozzie. Looking forward to the mess...

Might have to invest in one of Toby's bleeder kits down the road.

Steve

[content22207]

If you reroute the radiator bleeder *UPHILL* to the heater core, the radiator will automatically bleed itself:
3030

Bill Robertson
#5939

[mluder]

If you reroute the radiator bleeder *UPHILL* to the heater core, the radiator will automatically bleed itself:
3030

Bill Robertson
#5939

I'm not sure I understand... That's what mine looks like now but there's no way for air to escape the system.

Steve

[DMCMW Dave]

If you reroute the radiator bleeder *UPHILL* to the heater core, the radiator will automatically bleed itself:
3030


I understand what you've done, and I've seen you mention it a bunch of times, but since the heater core is at a very high point in the system (as high as the top of the engine) I'm not quite sure why it's a better place to vent the radiator. If you follow the lines from the heater core they both go down, just as low as the piping that the factory connected the bleeder too. Also - under some circumstances (max AC) water flow through the heater core is shut off.

[content22207]

Air is forced out of the heater core as the water circulates. Happens within seconds. As mighty as those dreaded air bubbles are, flowing water is mightier.

Water flows through the heater core the instant the engine is started -- it doesn't have to wait for the thermostat to open.

Bill Robertson
#5939

[Ozzie]

I'm not sure I understand... That's what mine looks like now but there's no way for air to escape the system.

Bill modified the stock functionality. He routes a very long hose from the top of the radiator fitting (passenger side), to the heater core just behind the engine. Works for him, according to him.

You may be new here, Bill likes to modify his car in clever and unique ways, but it often isn't a solution for everyone.

Bill may also take offense at that well intended sentence above, and launch several threads about it here, some sure to include the word "nonsense", and then ultimately the mods move out those posting from here, to the "Ask Bill About Carburetors" thread.

[content22207]

Bill modified the stock functionality. He routes a very long hose from the top of the radiator fitting (passenger side), to the heater core just behind the engine...

Heater core is underneath the dash board, not in the engine compartment (heater core lines themselves are right behind the fuel pump access panel). My bleeder hose is only about 2 feet long.

Bill Robertson
#5939

[Ozzie]

Thanks for the correction, that does make it more practical that routing it to the water valve as I had thought.

[John U]

I"ve bled my system three times now without any issue (stock set-up). I use the bleeder on the thermostat housing after raising the rear of the car as high as possible.

John

[mluder]

Bled the system with Ozzie's instructions. Not as messy as I thought it would be. Coolant came out at the radiator in a constant steady stream but I was expecting a gusher. Same deal at the engine... good flow but not supper high pressure.

Took it for a brief trest drive and all seemed well. I'm going to risk driving to work tomorrow - about 5 miles.

Thanks to all who chimed in.

Steve
#4456

[Farrar]

If you reroute the radiator bleeder *UPHILL* to the heater core,

Bill, does the heater core use the same size hose or did you use a reducing coupler?

Farrar