Possible head gasket

J Witt

Well-known member
So the car seems to be running OK, except the coolant is disappearing. I did a 10 mile run at speeds up to about 60, the temp got to 220 (50/50 antifreeze). I slowed it down and found a spot where I could let it cool off some, then drove back to the shop. The temp gauge was fluctuating, which told me the coolant was low. Sure enough, at least a gallon is gone, the level is below the fins.

Since I can't find any coolant leaks and the bottom of the car isn't wet, my guess at this point is the engine is eating the coolant. I'll run a compression check soon, before she's driven again. It has a pressure overflow valve and a sealing rad cap, both appear to working properly. No leaks anywhere else. It runs very nicely when below 180 degrees.

The engine has been hot like this a couple of times recently, each time I have thought I found the source of the heating which was various stuff like the fuel pump letting the engine lean out, and the ignition system faulty.

This is a stock 85 hp engine, with iron heads. Anyone have suggestions for procedures/parts to have before pulling the heads? I assume the heads come off without the intake systems or exhaust manifolds.

What would be the best choice for head gaskets?

Thanks in advance for info or comments.

John
 
Do an exhaust gas test via the radiator. The kit is available at any NAPA store, about $30.00 as I recall. That will confirm a leaking gasket or worse yet a cracked block.
 
Good idea. I did check to see if there were bubbles in the rad, but didn't see anything.

Thanks
 
do a compression check, if you have a blown head gasket two cylinders next to each other will have the same compression reading, ive found that most heating problems are radiator related, cores plugged, buy or borrow a infrs red heat gun to shot the radiator with, radiator should be hot at the top and fairly warm at the bottom of the fins, a plugged radiator will show up on long hill pulls, or high speed runs
 
I haven't found the exhaust in the coolant tests to be vert actuate. I've had them show no exhaust gas, with a failed head gasket.
They only prove (maybe) that there's no exhaust gas in the coolant, they don't prove the head gasket, block and head are ok, the only real way to tell is to tug the heads and look for yourself.

John,
Parts needed on hand for the job are just the head gaskets. Exhaust and inlet are not disturbed, they stay on the block.
The heads can be a chore to get off, patience is God here. Search on here for a bunch of tips to get them off if there being a problem getting them off.
Martin.
 
I would top the coolant up ans go for another run and check it
As it you have thermostat with out the bleed hole then you could have have had air in the system When you filled it up giving you a false reading of been full then during your run as the thermostats would have open letting the air out.
Granny
 
My 33 did a similar thing,it would get hot and have low coolant, I tried all sorts to find the leak,head gaskets etc etc, turned out it was leaking from the water pumps at speed and up long hills,and as i only used water and it was always being topped up with clean water I could not see any stains,but on stopping at the top of a long climb,and lifting the hood I saw the fine spray from the water pump seals ,replaced the pumps and problem fixed .
Lawrie
 
Here's what I've done since the original post:

compression test, plugs out throttle blocked open, crank with starter:

Left side front to rear, 52, 52, 52, 55

Right side front to rear, 48, 54, 68, 52

As you can see these seem to be low to me and aren't very consistent. Some oil in R-1 jumped the pressure up 10 psi to 58.

The plugs are fairly even in color, black around the shell, very light tan insulator and a frosty white on the ground electrode. Coolant, I think.

I had retorqued the heads right after I got the car, but that was before warm weather set in.

This morning there is a new leak that appears to be coming from the core to header tank joint somewhere. I think this may be the result of pressure from getting hot, as it just started last night -- a pint or two of coolant is on the floor. So at a minimum the radiator is headed for some work.

No thermostats installed currently, and no apparent leaks to begin with. Water pumps are new from Joe's, ball bearing and ceramic seals with bigger impellers than the stock pumps. Looking in the header tank with the engine idling shows very active coolant circulation.

Looks like some shop time coming up.

Thanks for all the comments and suggestions.
 
Picture of the plugs:
 

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Not sure what year you are working with but the 85 would indicate what is usually a non pressure cooling system. No thermostats and larger impellers also indicate a lot of coolant flow. The early v8s are bad with stock systems pushing coolant out the overflow. I have put Skips low pressure valves on my cars overflow tubes and run thermostats. That stopped the coolant loss.
 
I know some of the guys say that the Exhaust gas test did not work, so be it! I have never had it fail over 60 years working on old fords. It must be done properly. Skips low pressure stuff works very well. We had a 1935 engine use cooling fluid with new pumps, it turned out to be that the head gaskets failed after the new pumps were installed, I think the extra coolant flow was to much for the head gaskets, that may have been ready to fail anyway. When I took the heads off I decided to do a full rebuild to the tune of many dollars later, now all if fine.
 
I know this is a little off topic, but compression readings aside, isn't that about the color you want to see on your plug electrodes? My buddy says is "the color of a broken open Hershey bar".
 
The plugs may have just a slight difference that we don't see on the photo's. Also your compression could be good with just a slight difference in the plug. Lots of different things to analize. I still will stick to a exhaust gas analyzer to start with. JMHO Your compression seems low overall, you may need a total rebuild or a valve job.
 
Radiator removed today (sure have to get a lot of stuff out of the way in that narrow nose). Will deliver to the radiator shop on Monday. I'm planning to pull the heads and have a look over the weekend.

I'll probably go ahead and pull the intake too and have valve lash check at a minimum. I'll be happier knowing what the condition of it all is. I'd like to do a longer tour this summer with confidence that everything is good.
 
I know this is a little off topic, but compression readings aside, isn't that about the color you want to see on your plug electrodes? My buddy says is "the color of a broken open Hershey bar".

The only thing that concerns me about the color is the frosting on the ground electrode. When it is cool, the car runs fairly well, and doesn't act too lean or rich.

John
 
Radiator is out to go to the shop tomorrow to get the header tank fixed and clean out. I took the heads off and it appears there might be some leakage around the center holes between centers. Also there is a rusty edge along the lower edges above the exhaust manifolds.

I think there has been some leakage to the outside there. I may have never seen it because it would have been leaking on the exhaust and evaporating. I hope to take everything to one of the local experts for a look, and then make a plan for the fix.
 
One easy way to check for leaky head gasket is to remove the upper radiator hoses from the water necks on the heads . Then pour water in the necks up to the top then remove the belt to keep the pumps from turning. Crank the engine and look for bubbles in the water neck.
 
Got the radiator back this morning after boil out and three core leaks patched. I spent a couple of hours straightening fins and general clean-up. Next is a refinish in appliance epoxy spray (Just the tanks and side frames).

Since then, we agreed with Josh Mills to go through the engine and rebuild as necessary. Wife and I decided we didn't want to go touring with the car and worry about patched up systems failing. So I am pulling off as many parts as needed for the engine removal while waiting for a slot to open up in his shop. I can do the scut work, but no longer have the resources for pulling engines, disassembly and doing all the prep work a good rebuild takes.

Now draining oil and cleaning bolts, that I can do. ;)

John
 
I don't see comments on whether this is a pressure system or not. If running an open system, as in 32-late 30's, you might read old posts on this. What you describe could be the normal operation. At 60 mph, the coolant is going to be pushed out. You might be chasing something that is perfectly normal.
 
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