Afterboil

I just recently got my rebuilt 200ci running. It runs nice, but I noticed when I shut off the car, the coolant in the upper radiator hose starts to boil. When the car is on, the temperature is good and I can feel the thermostat kicking in normally. The timing is set to 12 degrees (automatic transmission), curb idle at 550rpm (Holley 1940), new water pump and new radiator hoses. There may be a little more water in the system as I ran it with only water until I got the car running smoothly.

Is afterboil normal with these engines? If not, do you have any suggestions on where to start? I may try my old upper radiator hose to compare. Thank you in advance.

50/50 coolant mix will allow the temps to come up higher without boiling.

50/50 is in there, I just only drained the radiator and not the full system when I added it. The ratio may be water 65 / coolant 35.

If afterboil is not a sign of something wrong, I may wait and drain the full system after 500 miles.

i have never had an issue with after boil in my small sixes. start with the basics, do you have a fan shroud? do you have proper airflow through the engine compartment? are you sure the initial timing is 12 degrees? did you properly burp the radiator to clear the cooling system of air pockets?

when you drain the radiator, you also drain a substantial portion of the rest of the system as well.

Make sure that you have purged as much air from the system as possible. When you fill the cooling system, run the engine while you top the radiator off. Leave the cap off and run it until it gets warm and the t-stat opens. Keep running until all the air bubbles out. Guaranteed there is a large air pocket in there somewhere. At some point the coolant level will drop and you will have to refill with 50/50.

I had that exact same problem and this is what solved it. Make sure there is no more than 1/2" of air at the top of the radiator before you cap it.

Thank you everyone, there was air in the coolant system. Just wish I had remembered to place a rag over the top as it made a big splash and a few drops may have gotten into the oil (was multi tasking).

When I turned the car off, there was no afterboil so I think this is resolved.

I was going to say you have a heat soak issue but an air block will do the same thing. You have to make sure you have all the air out in future.

That's right. Cool23 is on to it.

Just check its not fuel precolation.

There is another three bits of trick kit Ford Australia used from 1982 to 1992 on the X-shell Falcons. It like a Fast Eddy Speed Bleeder for brakes, but its for the cooling system.

http://www.fasteddysports.com/?page_id=3&product_id=810



The X-flow Falcon has a purge valve that bleeds air out of the upper radiator hose housing. Just like the Nissan 200/240sx.


Everything from the 170 iron non cross flow to the last 1992 and alloy heads have the same kind of radiator hose thermostat outlet casting (there is a small hose size difference), but on the X-flow it is angled or clocked it around a little. One of the securing bolts has a little air bleed 'petcock' on it, and you bled air out after the engine has cooled from a trip when the engine was coolant was changed.


The removal of air removed ineffective cooling via cavitation, or entrained air.


The second other thing 1982 XE-1992 XF X-flow Falcons did brilliantly was how the X-flow I6 2-bbl engine delt with hot fuel handling by excess fuel bleed back fuel lines.. This was a 1972 on German Pinto engine 1.3/1.6/1.8/2.0 liter and 1983 on wards Ford 5.0 HO 4-bbl GT idea, but it took many years for Ford Australia to adopt it.

the US set up used a Precision Mechanical Fuel Pump Part # M23029 Line on the 4-bbl HO GT 5.0

http://www.oreillyauto.com/site/c/d...ck=Search_C0401_1133682_-1&pt=C0401&ppt=C0025



And v Aussie 3.3/4.1 x-flow return line pump with a huge vapour chamber



Lastly, the Wber ADM 34 carb (and the 4180c 4-bbl as well I think) had an idle stop solenoid to stop running on. Thse three things make a huge difference on a hot Ford I6 or V8.

Those of us lucky enough to have used the base model XD and XE Falcon GL 5.8 125 mph, sub 16 second quarter mile 200 hp performance machine of the Aussie Cleveland V8 missed out on all these advances. I think it missed out on the cooling bleed petcock, , it used the old non bleedback fuel delivery system, a defective heat seaking plastic Thermoquad 9600 4-bbl, and with greatly reduced radiator air flow with the smaller grill inlets, and it sadly missed out on the brilliant 4180c 4-bbl 5.0/5.8 and 370/460 truck fuel system. It often suffered hot fuel handling problems and post operational boiling. When people slapped the more common closed chamber 302C 2V heads on them to boost power via a Boss 351 style 11:1 compression ratio, half the time, they'd diesel and you couldn't turn them off.


A forth trick if it is hot fuel handling problem is this.




MustangGeezer used one on his old log head too

Hi all.A little trick that I learned long ago was to have the vehicle nose down to drain,and nose up to fill the cooling system.Has always worked well for me.YMMV.
Good luck.Have fun.Be safe.
Leo

woodbutcher":2nikdpzi said:

Hi all.A little trick that I learned long ago was to have the vehicle nose down to drain,and nose up to fill the cooling system.Has always worked well for me.YMMV.
Good luck.Have fun.Be safe.
Leo

Click to expand...

good trick. one that works almost as well is to drill the thermostat with an 1/8" bit to create a bleed hole. set that bleed hole at the top of the thermostat so that when you fill the system, trapped air can escape. it doesnt completely end the problem, but it does minimize it substantially.

rbohm":3gyadjbg said:

woodbutcher":3gyadjbg said:

good trick. one that works almost as well is to drill the thermostat with an 1/8" bit to create a bleed hole. set that bleed hole at the top of the thermostat so that when you fill the system, trapped air can escape. it doesnt completely end the problem, but it does minimize it substantially.

Click to expand...

Click to expand...

Mercedes thermostats come new that way, and you have to take care to ensure you install them with the hole in the right direction or - surprise - you end up with air pockets.

Have noticed thermostats have the hole from the factory for years.
Good luck.Have fun.Be safe.
Leo