Coolant Escape from Overflow after shutdown - Any ideas?Monaco Wagon 383

413

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I must question the advice to fill radiator to the top, even with a recovery bottle. Many old time radiator repair men (are there any other kind?) say to leave the air space in there for a cushion. Air expands and contracts, coolant does not. Leads to radiator leaks.
 
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ceebuddy

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True. If you look closely, you can see the coolant puddle in this 1969 Imperial press photo:

69imp_press04b.jpg


Or in this photo found in the new-car issue of the Plymouth Traveller:
20190218_224023.jpg
 

livininharrow

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True. If you look closely, you can see the coolant puddle in this 1969 Imperial press photo:

View attachment 261624

Or in this photo found in the new-car issue of the Plymouth Traveller:
View attachment 261623
looking at both of those photos it appears the cars are on an upward grade. this would lead me to believe the drivers just didn't make it quick enough to the bushes. hence the fluid being in front of the vehicles and not underneath. hope this helps.
 

DJAstral

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Get rid of the lever rad cap and buy a good 16 lb VENTED cap plus a coolant recovery bottle. (NOT just an overflow) Run the hose from the rad to the bottle and fill the rad all the way to the top plus about an inch inside the bottle. No more puking, larger coolant capacity.

View attachment 261615
Thanks for that, I fitted a coolant recovery system yesterday & am changing the cap as you advise for a regular one today or tomorrow when it arrives.
 

DJAstral

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Common for the threads to be eaten away right under the bolt head. If that happens they will break easily when trying to remove. So apply heat to the iron housing where the bolt threads are. Don’t heat the water neck, it won’t do anything. You need alot of heat so use an oxy acetelyne torch. A propane torch is not hot enough.

View attachment 261614
Thanks for that, I’m SO scared of breaking the bolts but will heat as you suggest.
 

DJAstral

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I found that with most of these older Mopar's it was pretty normal for them to pee small amounts of coolant. Usually after they do it a few times they will stabilize the coolant level and stop doing territory marking. If you are worried about a head gasket leak, Auto Zone and most other major parts houses have a hydrocarbon tester to check for head gasket leaks and the tester is usually free to use.

Dave
Hi there, yes it is just a very small amount & it does seem to stabilise like you say but this is one of those many occasions when I wish I lived in the US! ... we don’t have such stores over here in Scotland, UlK sadly but I’ll track one of those things down if I suspect the gaskets thanks. There is not a fix-it culture over here, most folk drive new, boring, Japanese or European hatchbacks or throw-away 4x4s
 
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TxDon

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I must question the advice to fill radiator to the top, even with a recovery bottle. Many old time radiator repair men (are there any other kind?) say to leave the air space in there for a cushion. Air expands and contracts, coolant does not. Leads to radiator leaks.
With a coolant recovery system the coolant expands into the bottle when it expands and is drawn back into the rad when it cools. No strain on the rad, all cars have used this system since the 1970s.
 

DJAstral

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Thanks for that seems like a better system altogether. I converted it yesterday & put a new 16LB standard vented cap on today. I’m going to continue to maintain the correct level in the radiator & not overfill it though, so as still to allow for expansion.
Looking forward to trying it soon, will post my findings when I get the chance.

Thanks to everyone once again for all the prompt responses and helpful advice. This is such a great forum, so glad I found it!
 
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Snotty

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Thanks for that - looks good, very helpful.

for that
You're welcome. I put one of those on the '62 I had, as well as my Son's Gremlin. I bought them at the annual Western Street Rod Nationals in Bakersfield, CA. You can probably find one in a street rod magazine.

20150711_105812.jpg
 

413

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With a coolant recovery system the coolant expands into the bottle when it expands and is drawn back into the rad when it cools. No strain on the rad, all cars have used this system since the 1970s.
I Understand how it works. I can see the value. But. Only of the radiator was designed for that.

The point is that the old radiators need to have airspace inside to allow for expansion and contraction. If no air space then every part of the system does all the expanding and it will lead to cracks and leaks. Example: old heater core and radiator failure.
 

BillGrissom

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I'll 5th the suggestion that an air space at the top of the radiator is normal. As example, for a time I would notice the coolant level in the radiator being down ~2" below the cap in our 2002 T&C 3.8L V-6 van, so would top it off. After repeating many times, I noticed the level in the coolant reservoir had increased. I read "air at top is normal", so stopped topping it off. Indeed, most Owner's Manuals today tell you to check the reservoir level (and don't fool w/ radiator cap), which is probably simpler than trying to educate owners on the "why".

If thinking "2002 engine is totally different", my 3.8L has pushrods, 2 valve/cyl, and the rocker arms are shaft-mounted stamped-steel and look almost identical to the rockers in my 1965 383 engine. The only differences are: 2 less cyl, alum head, roller lifters, oil-pump integral w/ timing cover, and modern fuel and ignition controls. All of these can be upgraded on my 1965 engine (exc. #cyl & oil pump).

BTW, I switched to Evans Waterless Coolant in 6 of our 7 vehicles, so no more boil-overs or corrosion worries. Downside is that if you do have a small coolant leak you are motivated to find it ($42/gal).
 

Brent Martini

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Just wondering what recovery bottle did you use ? I’ve been considering one for my 72 imperial and 1970 charger
That is REALLY helpful! Thank you so much for that - I’ll give this a go today. I hadn’t considered adding this & am sure it will help.

Job done, coolant recovery bottle fitted to catch & return the max 1/4-1/2 cup of coolant that comes out as you suggest.
 

DJAstral

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Just wondering what recovery bottle did you use ? I’ve been considering one for my 72 imperial and 1970 charger
Hi there Brent, you’ll probably be quite amused to learn that the coolant recovery bottle I used is a 1.5 Liter Kirkland Golden Margherita Mix square plastic bottle filled 1/3 full of neat coolant!!!
I drilled a hole to match the size of radiator overflow hose (which I trimmed slightly so it sits about 1 inch above the bottom of the bottle) and another two small breather holes in the screw on plastic cap.
The size of it snugly fits in between the radiator and the inner bracing plate next under where the battery tray sits. I secured it with a couple of big zip ties. Actually looks quite pleasing, although not original & best of all cost me nothing at all! Works a treat so far & because the bottle is clear I can keep an eye on things.
 
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