A Lovely Old Spinster, Virgin No More!

Gerald Morris

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Now C-body Moparians, we can hopefully conclude this series inspired by the overheating problem in our otherwise EXCELLENT barn find, Gertrude!

Nearly 54 years have passed since this car's engine had daylight fall upon its pistons! After patient, painful attempts to correct a rapidly worsening overheating problem, I finally was compelled by circumstance to do a risky, unpleasant operation on this engine and open the cylinders to daylight in hope of finding WHAT has been driving the running temperature of this otherwise SUPERBLY PRESERVED old machine to a level which assures destruction. To wit: the Old Virgin started running a DEADLY FEVER, and ONLY SURGERY might cure it! So, I've diddled Dear Gertrude, who will be a spinster no longer. Now, let us pray I can effect her Cure.

Prognosis: Gertrude's engine shows REMARKABLE preservation and maintenance. It runs extremely well, having passed the rigors of the City of Tucson's Emissions test with a level less than HALF that allowed by the City. The car accelerates most satisfactorily once at a normal operating temperature. Here lies the Problem. After warmup to ~190 F, the thermostat opens, momentarily cooling the engine with a flood of cooler coolant from the radiator, but then the already rapid ascent of coolant temperature, instead of abating, increases exponentially, reaching an unsafe level (over 230F) in 10 minutes, and pressurized boiling point (~250F) in less than 20 minutes. The operating range of this engine has fallen to less than two miles, and was decreasing with every run. A liquid sealant was introduced to the coolant to utterly NO avail. Other common overheating remedies such as adjusting timing, introducing a pusher fan, enriching the idle mixture all availed nothing, with the overheating worsening with every run cycle.

Only opening the cylinders offered any hope of finding and correcting the Problem.

Gertrude's Constipated Coolant Ports, Even Numbered Cylinders
open-block-even-numbers-blocked-coolant-ports.jpg

Attend to the red circled regions in the graphic above: The first coolant port, as coolant circulation ideally was designed to flow in the cylinder heads, channeling coolant between cylinders 2 and 4, is TOTALLY BLOCKED WITH CARBON BLACK!!! Recall how the spark plug from Cylinder 4 has been found twice fouled, and is the ONLY spark plug in this engine thus compromised. I expected a head gasket leak, which, I thank the Lord, doesn't exist, BUT, with a blocked coolant port, even the superbly preserved steel shim gasket shown below would be eventually doomed, if the block or head didn't crack first.
complete-Mopar-steel-shim-head-gasket.jpg

So, as regrettable though it is to disturb the cylinder head seal, the severe escalation in overheating warranted investigation and remedy. A conventional (Blue Devil) organic acid cooling system flush had been implemented several weeks earlier, which cleared the radiator of accumulated scale, but clearly couldn't dissolve the non-polar carbon black deposits blocking the coolant ports on the cylinder head. There was no more time or margin for further experiment. The problem had to be solved immediately, by direct mechanical opening.
blocked-coolant-port-cyls-2-4.jpg

First head port TOTALLY BLOCKED!

badly-obstructed-coolant-port-cyls-4-6.jpg

Some trickle through middle port possible still, just....

badly-obstructed-coolant-port-cyls-6-8.jpg

Back head port also still capable of a TRICKLE, but no more!

Suffice to say, I'm not surprised now that the block below this head would get as much as 20 degrees Fahrenheit hotter than the rest of the engine! There were several cups of coolant STILL IN THE HEAD DESPITE MY SHOP VACUUMING OUT THE BLOCK OF COOLANT BEFORE OPENING THE BLOCK! Most of this spilled into the cylinders, which I QUICKLY VACUUMED OUT, but we planned to drain the crank case oil after this little surgery regardless.

I'll open the odd numbered cylinders after sunrise today. We want to make DAMNED SURE no other nasty little surprises in coolant FLOW await us!

This engine REALLY IS in EXCELLENT CONDITION, given its age! It runs VERY nicely too, sans thumping cylinders from stuck lifters and such. With God's help and St. Joe's intercession, we hope to clean off the mating surfaces of block and head, then install the FelPro gaskets I bought as part of a head set over a year prior, mindful of the need of a valve job for Mathilda then.

I'll use the rest of that head set too I imagine, except the valve stem condoms. That can wait for now.

Pray for us. We need to get Gertrude on the street ASAP!
 
Oh wow, that'll do it for ya! :eek:
Looks like you have some work ahead of you but it must've felt good at least to find the problem.

I wonder though, what could've caused this? Is this something to look for on any high mileage engine?
 
Oh wow, that'll do it for ya! :eek:
Looks like you have some work ahead of you but it must've felt good at least to find the problem.

I wonder though, what could've caused this? Is this something to look for on any high mileage engine?
Infrequent cooling system flushes would be my first guess.
 
Never done a cooling system flush, but always kept good coolant in the systems.

One possible issue with a coolant system flush, especially the aggressive ones, is that if they remove the scale from the engine block, they'll also remove scale from the block and heads' core plugs, possibly causing them to leak, too. NOT to forget about the heater core! Sometimes, less is better, by observation, plus good coolant quality.

Just some thoughts,
CBODY67
 
Good that you found a real problem here that will definatly make it run cooler. And the head gasket was not the problem, they look to be in great shape after 5 decades on the job.

So it looks like the next step is remove the freeze plugs and see how much foreign material has accumulated at the bottom of the cooling passages. Time is now to get it out of there. The center drivers side and center or rear passenger side freeze plugs. should be accessible. May be able to move the H pipe to gain access. A good tool to reinstall cup plugs in the car is a cut off torsion bar. They go right in.

But since you chose to ignore using thermocure to flush the cooling system, ignore removing the block plugs in favor of soaking the piston rings in coolant just dismiss the above idea as an unnecessary waste of time also.

See all the rust in the large cooling passages at each end of block. The thermocure would have not left a brown orange rust there, it would be clean gray metal.
 
As I watched the tech pull the lh head off of the '66 Newport (back in about 1970 or so), other than draining the radiator, there was some residual coolant which ended up on the pistons. I asked about that and he said he's soak it up in shop towels and all would be fine. And it was.

Granted, a larger amount in the oil (once it might get past the rings) would be an issue, in that smaller amount, it was not, in this case.

That was not the only time, over the years, I've seen coolant on pistons, which was quickly soaked-up with no issues of it getting into the crankcase. FWIW

Just some thoughts,
CBODY67
 
Coolant doesn’t belong in the cylinders, so why get it in there? We should work smarter. Nothing bad about draining the rusty coolant out of the sides of the block. May get an ides of what has collected down there.

I was a flat rate mechanic for years, I’ve seen plenty that shouldn’t be done again. And if the customer sees any of it, just tell them that everything is “fine”
 
Coolant doesn’t belong in the cylinders, so why get it in there? We should work smarter. Nothing bad about draining the rusty coolant out of the sides of the block. May get an ides of what has collected down there.

I was a flat rate mechanic for years, I’ve seen plenty that shouldn’t be done again. And if the customer sees any of it, just tell them that everything is “fine”
Tore down a 289 Ford engine that was rusted like that one. The perils of running straight water in the cooling system in that instance.
 
Oh wow, that'll do it for ya! :eek:
Looks like you have some work ahead of you but it must've felt good at least to find the problem.

I wonder though, what could've caused this? Is this something to look for on any high mileage engine?

I would if it overheats. As loathe as I was and AM to open the block, my efforts self-evidently were justified. NOW I must open the driver side, as its very likely that the head ports there won't be MUCH better off than they were here. I also strongly suspect that damned coolant heater, which was left attached and open throughout the year, regardless of temperature. THAT THING SCREWED UP THE PROPER COOLANT FLOW!!!!! I would never recommend one of these gadgets. IFF the engine needs pre-warming before attempting to start, as admittedly gasoline engines do in sub-zero temperatures, the RIGHT WAY to achieve this is with an electric TAPE, usually of nichrome wire.
 
Infrequent cooling system flushes would be my first guess.

THAT, and that damned coolant heater pump, which diverted coolant flow from the proper channels through the head, short-circuiting the flow back to the pump. Thus, coolant would remain STAGNANT in the HEAD for possible minutes in runtime. I didn't like the look of that gadget the moment I saw it. Wasn't wrong, was I?
 
Never done a cooling system flush, but always kept good coolant in the systems.

One possible issue with a coolant system flush, especially the aggressive ones, is that if they remove the scale from the engine block, they'll also remove scale from the block and heads' core plugs, possibly causing them to leak, too. NOT to forget about the heater core! Sometimes, less is better, by observation, plus good coolant quality.

Just some thoughts,
CBODY67

I somewhat concur with your view here. Note that after my flush, the radiator started leaking up near where the tank attaches to the core on the passenger side, engineward. Then, as the overheating worsened, it would spray out of that damned seam when the cooling system got badly over-pressurized. Yes, scale oft consists in part of the Original Metal meant for the structure, so removal can actually weaken it.

BUT, SCALE ALSO OBSTRUCTS! Look at the picture I just took in the broad light of day here:
even-num-block-top-w-coolant-ports-illuminated.jpg

That crap silted up the head too.
scaled-up-rear-coolant-port-head.jpg


The case of this excellent old motor underlines my point nicely:

Better to flush to avoid overheating. Leaks can be bad, but overheating is WORSE.

Still, each case must be assessed on its own circumstances. FWIW
 
Good that you found a real problem here that will definatly make it run cooler. And the head gasket was not the problem, they look to be in great shape after 5 decades on the job.

So it looks like the next step is remove the freeze plugs and see how much foreign material has accumulated at the bottom of the cooling passages. Time is now to get it out of there. The center drivers side and center or rear passenger side freeze plugs. should be accessible. May be able to move the H pipe to gain access. A good tool to reinstall cup plugs in the car is a cut off torsion bar. They go right in.

But since you chose to ignore using thermocure to flush the cooling system, ignore removing the block plugs in favor of soaking the piston rings in coolant just dismiss the above idea as an unnecessary waste of time also.

See all the rust in the large cooling passages at each end of block. The thermocure would have not left a brown orange rust there, it would be clean gray metal.

Oh I think I WILL check the jacket for crap now. I use a nice big socket to drive the expansion plugs in. Yes, the plug in the middle of the passenger side is EASY to get to, and I am blessed with a nice horde of brass plugs. After all, Thermocure wouldn't have dissolved that carbon black any more readily than any other organic acid solution would have. Remember, carbon crystallizes as diamonds. Carbon black->graphite->anthracite->diamond is the normal formative sequence. I admit that maybe Thermocure would have dissolved the calcium scale better than the Blue Devil did. I won't use it again. I'll try Thermocure, FWIW and will see..... Might even try it as soon as I get Gertrude's plant back together. BUT, since I've opened ONE side, I now MUST do the other, to install the same size FelPro gasket as will go in on the passenger side. I DARE NOT RE-USE THAT SHIM HEAD GASKET, DESPITE ITS APPARENT GOOD LOOKS!!! I lament this too, but re-using head gaskets is a Cardinal No-No, as I think you'll agree.

I SAS* rejoice that the head gasket is fine, and didn't leak. But those steel shim gaskets CAN leak, especially if rusted a bit. I saw this 2 years ago when harvesting some closed quench heads. While most of the gasket looked fine, a nasty little bit had oxidized, making a path of opportunity for high pressure gasses to blow through, as they did in that case.

*Sure As ****
 
Oh heck no don’t reuse those head gaskets. Im still pleased how good the engine looks inside. But like Rosanne Rozanadana says it’s always somethin’

 
As I watched the tech pull the lh head off of the '66 Newport (back in about 1970 or so), other than draining the radiator, there was some residual coolant which ended up on the pistons. I asked about that and he said he's soak it up in shop towels and all would be fine. And it was.

Granted, a larger amount in the oil (once it might get past the rings) would be an issue, in that smaller amount, it was not, in this case.

That was not the only time, over the years, I've seen coolant on pistons, which was quickly soaked-up with no issues of it getting into the crankcase. FWIW

Just some thoughts,
CBODY67

That dousing surprised and aggravated me, especially after pulling the damned bottom hose and draining it with the shop vac, which usually and did this time too, suck out over a gallon of coolant. Of course, I don't go pulling cylinder heads every day, and pray I needn't again for a LONG time!

It doesn't worry me though, as wife and I agreed right away before ever a wrench touched bolt for this little job that the crankcase oil WOULD be drained and changed. After all the heating and cooling, plus catching the devil-only-knows-what debris, that motor oil SHOULD be changed!

I sucked up, then wiped muy pronto, for terror of what might occur. I don't worry about this, though will probably use the air compressor AND open the damned drain plug before cracking the driver side.
 
Oh heck no don’t reuse those head gaskets. Im still pleased how good the engine looks inside. But like Rosanne Rozanadana says it’s always somethin’



Nooo **** Hoss! BTW, have you any preferred gasket sprays? I was just fixin to PM you on this, but your prompt attention to my thread, (THANK YOU!!) spared me the need.
 
Coolant doesn’t belong in the cylinders, so why get it in there? We should work smarter. Nothing bad about draining the rusty coolant out of the sides of the block. May get an ides of what has collected down there.

I was a flat rate mechanic for years, I’ve seen plenty that shouldn’t be done again. And if the customer sees any of it, just tell them that everything is “fine”

Yes, I should have pulled the plug instead of relying on the shop vac to suck everything out. Still, I don't know if gravity would have drained that head any more than the Rigid shop vac would have. Still, you're right: "Hurry the **** UP!" oft HURRIES THE FUCKUP!!!
 
Use the felpro blue head gaskets dry. That is their recommendation and they know something about gaskets. They are great gaskets But the 17 head bolts really help that.

Final clean the block and head with brake clean and paper towels until they are clean when wiping the surface.

It’s just so easy to remove the block plugs and that’s the only way to drain the side of the block and head. And it may or may not have dripped out of the head past that blockage in a few hours. The shop vac won’t get it out, but now you know that.
 
Tore down a 289 Ford engine that was rusted like that one. The perils of running straight water in the cooling system in that instance.

Worse yet, I strongly suspect this one had TAP WATER FROM COCHISE COUNTY WELLS in it! Combine such super-hard water with repeated heating to precipitate calcium oxalate crystals, and the result is self evident. Hell, I might collect some specimens and have a spectrograph run at the U
Use the felpro blue head gaskets dry. That is their recommendation and they know something about gaskets. They are great gaskets But the 17 head bolts really help that.

Final clean the block and head with brake clean and paper towels until they are clean when wiping the surface.

It’s just so easy to remove the block plugs and that’s the only way to drain the side of the block and head. And it may or may not have dripped out of the head past that blockage in a few hours. The shop vac won’t get it out, but now you know that.

THANK YOU THANK YOU THANK YOU!!!! GOOD TO KNOW!!! Yes, I had already marked my stash of brake-klean for the cleansing job. I even have a can or 2 of the good carbon-tet stuff, if needs be. So, FelPro blues DO go in dry? THAT'S a COMFORT!

I labelled each head bolt as I removed it too. I figure if it held pressure for 53 yrs where it was, I'd best return it to its proper place.

OK, I need to crawl under Trudi now and do a bit of W-O-R-K. Mamas doing us all the FAVOR of taking the Little Gremlins w her this afternoon too.

Pray for me or otherwise wish us well. I don't get much quality time like this.
 
I'm not seeing anything in your photos that I haven't seen before in a 50+ year old engine that hasn't had the best of care. Most of the blocks came with cooling passages loaded with foundry sand level with the bottom of the core plugs in the side of the block. It takes a lot of digging and work to get them all cleaned out if you are not going to strip the engine and take it to a machine shop for a boil out and a rebuild. If I were you I would clean it up best as you can, flush the heck out of it and put it back together. That is really all you can do without taking it out and going through it completely.
 
When I bought my 68 Newport in 2005 it last ran in 1974.
I had the same problem with the cooling passages plus the block was full of crap in the water jackets right past the freeze plugs.
Nothing new from a car that sat for a ling ling time.
Glad you found and is addressing the issue.
Being an Export model she is a rare beast.
 
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