New engine instantly gets hot

[grocery getter]

you really need to get some more data before pulling the head.what happens if you pull it and see nothing unusual,then what?

have the mechanic rule out exhaust in the coolant.


ask him if he double checked the timing mark on the balancer when he timed it.
put a garden hose in the bottom radiator hose and see if you get flow out of the top hose.

again, what is the gauge saying? remember water boils at 212 f (14.7 psia) that's not so hot to kill an engine.

my money, if it's really overheating and only in 5 minutes is.... exhaust in the coolant.
with a smaller bet on timing or A/F ratio

 

[MustangSix]

This is one of the most common failures in my profession. I see engineers all the time who find a potential solution to a problem so sexy and mentally stimulating that they become blinded to the obvious explinations right in front of their face. Its only after expending large amounts of time and the companies money proving to themselves that they were mistaken do they come back around and realize the solution was simple all along. (computer doesnt boot? before you dissect the power supply looking for unanticipated eddy currents, try plugging it in!) KISS.

Sounds like my daily drill. Mostly with mechanical engineers who still don't understand the science and art of mechanics. Just try to convince one of these geniuses that, a. while yes, you can make a #6 screw with 200TPI, it is expensive and not practical, and b. screwing said stainless screw into an aluminum assembly can usually only be performed successfully once..... :x Now go design something not so stupid...

 

[Bort62]

This is one of the most common failures in my profession. I see engineers all the time who find a potential solution to a problem so sexy and mentally stimulating that they become blinded to the obvious explinations right in front of their face. Its only after expending large amounts of time and the companies money proving to themselves that they were mistaken do they come back around and realize the solution was simple all along. (computer doesnt boot? before you dissect the power supply looking for unanticipated eddy currents, try plugging it in!) KISS.

Sounds like my daily drill. Mostly with mechanical engineers who still don't understand the science and art of mechanics. Just try to convince one of these geniuses that, a. while yes, you can make a #6 screw with 200TPI, it is expensive and not practical, and b. screwing said stainless screw into an aluminum assembly can usually only be performed successfully once..... :x Now go design something not so stupid...

Yeah, My problem is I am on the engineering side of the fence. If you can't beat em...

 

[l3n]

Since it's not draining with the radiator removed and the thermostat open, I'd say there's probably a pretty major clog in the water jackets somewhere. I ignored that possibility the first time around since the engine had just been rebuilt, but with that kind of flow problem, it's entirely possible that the block isn't really getting that much coolant in the first place.

 

[66 Fastback]

See, this is the crux of the problem. The type of thinking illustrated here is what leads to the "parts replacement" process of troubleshooting, which is unecissarily expensive as well as time consuming and potentially embarassing.

I don't know what kind of problem you have with my stating the radiator needed replacing. If I pull hoses and something does not drain, then there is a problem with the radiator and block. The iron corosion products in the radiator usually come from the block. The scales can form all through the system as can the sludges.

I see engineers all the time who find a potential solution to a problem so sexy and mentally stimulating that they become blinded to the obvious explinations right in front of their face. Its only after expending large amounts of time and the companies money proving to themselves that they were mistaken do they come back around and realize the solution was simple all along.

As far as this engineer is concerned, checking the basic components of the cooling system is adhering to the KISS principle.

Compare these comments to this advice that you posted before the "I told you so"

I would suspect some sort of internal engine problem

Granted the engine should take a bit longer than 5 minutes to overheat because it takes a certain amount of kilocal/joules/btu's etc to raise the temperature. But a leaking radiator cap could start boiling over in that time. It could also be a source of oxygen that created the corrosion products and or breakdown of the inhibitor packages in the coolant. We also may be assuming that there is a water in the block.

You may be overlooking something very important if you have a plugged radiator. When you fill the cooling system with coolant, how is the block going to get filled with coolant if the radator is plugged at the bottom? I'm not saying it is the cause, but it is another possible explanation for the lack of coolant in the block. So the plugged radiator could be the core problem to the symptons of rapid overheating if the block did not get filled with coolant. Checking and replacing bad components of the cooling system is adhering to KISS. Once those components check out then you go on to more sexy causes like "internal engine problem" that have an effect the cooling system performance.
But that is just the opinion of an old Aggie oil patch engineer.
Doug

 

[aahsac]

I'll try to answer all this the best I can, a lot of good feedback (and I mean a lot)

The original radiator was clogged, no question. There was no radiator shop conspiracy. The tubes I could see from the bottom radiator hose outlet were clogged. The radiator shop filled the radiator from the bottom and let it drain a number of times. We did the same with the replacement and the rate of drain was dramatically better (gush versus drain). I'm certain a clogged radiator was the cause of the overheating that badly busted the head and was the reason that the firsty owner put the car in storage in 1975 with 26,000 miles on it.

The mechanic that is working on my car isn't trying to do a bunch of stuff to run up a bill. He owned a garage for 35 years and is retired and only agreed to remove and replace the engine for me while I am packing to leave the state. Neither one of us expected to have to trouble shoot a motor rebuilt by a major rebuilder.

I believe that there is a severe water blockage. Again, timing is right on, no vacuum leaks. I wish I had written down the compression test readings but there was little variation across cylinders.

There have been a lot of good suggestions that I wish i was able to just walk out to the garage and try or to check but the car is about an hour north of me so it isn't possible.

Trust me, I'm not crazy about pulling the head off since it was my good head that we reused for a long block rebuild (the work ticket had in large capital letters DO NOT MILL HEAD). But the fact that the water sits in the head with the radiator removed tells me that there is blockage.

Your experience may vary.

Stephen
Plano, Tx

 

[Bort62]

I think we all agree that there is probably a significant blockage in the cooling passages somewhere in the block. Your recollection of a nominal compression test further suggests this.

It's not that uncommon actually. Rebuilt blocks, if not properly cleaned, have a bunch of loosened crud in the passages.

They can also have things like latex gloves, paper towels, etc.

I would pull the WP and go at it w/ a hose. If you don't get anywhere with that, you may have to yank the head and see what there is to see.

 

[flatford6]

First, check the lower radiator hose. When running the engine the water pump is pulling a vacuum in it and can collapse the hose effectively shutting off water flow. The stupid cheap wire in them that is supposed to keep them open rusts out at the first opportunity and for a small amount of wire, can make a supriseingly large volumn of rust. Check that and also the condition of the hose, the inside layer of the hose inside the braid can delaminate and cause the same condition. Never install a radiator hose, expecially the bottom one, with the iron wire. Do your self and your motor a favor and replace the wire with a brass brazing wire reshaped to be exactly like the iron wire. Also, check to see that the impeller is actually the right one, a rebuilder could have put in one from a reverse rotation water pump. As to a compression leak, it will tend to blow water out the radiator cap before overheating, the volume of leaking compression gas will displace water in the cooling system.

 

[Anonymous]

Pull the thermastat housing, remove the thermastat and reinstall the housing. Remove the upper and lower radiator hoses and remove the water pump.

Stick a garden hose in the housing and turn the water on.

Observe how much water comes flowing out of the big hole in the block where the water pump goes.

I'm going to guess its a flipped head gasket.

Also,

How do you know its getting hot? Steam and such gushing out from the under the hood or the stock temperature gauge?

Later,

Doug

 

[aahsac]

It gets really hot, starts blowing water. Turn it off ad it sounds hot in the head, if you know what I mean.

Our intent is to see if anything crazy is going with the head gasket, if not then the freeze plugs will come out to see if there is sludge, old freeze plugs, wadded up panties or somesuch in the block.

Since water stayed in the head with the radiator out (with a punched out thermostat) then I reason cooling water is not flowing up to the head.

Hopefully this will be cleared up in the next couple days.

Stephen
Plano, Tx

 

[l3n]

Keep us posted, I'm kind of curious how it all pans out.

I always thought leaving crap in the block (or just not cleaning it out properly) was almost impossible. Never realized it isn't all that uncommon. I really need to spend some time and learn how to rebuild the block myself...my old girl has zero blowby and no leaks to speak of, so it's not a pressing concern, but it'll come up eventually.

 

[Bort62]

Sounds like you've got a special case of discomfort here, if nothing else.

Flipped head gasket... I was under the impression that would lead to massive coolant leaking out the side of the block. I've never tried this out for my own benifit

 

[MustangSix]

I think the head gasket will leak if flipped.

Other possibilities relate to the temp gauge. Could be either a failed instrument voltage regulator or a short in the sensor feed causing the gauge to peg. Those are easy to diagnose.

 

[Bort62]

I know it was stated that the coolant starts spewing and it "sounds hot in the head"

But an unpressurized system will boil @ 212* F... which is not overheating. Is the system pressurized during these tests?

Localized boiling could easily occur in the head long before the gross coolant temperature exceeded this point, leading to "sounding hot in the head". Especially if something was restricting flow in the block or the WP was not working properly.

The sound of coolant bubbling and flowing around in an engine is pretty normal, anyways. Whenever I shut mine off it usually sounds like a coffee pot for a few minutes.

So, is it really overheating? Does the radiator cap pop open on you?

 

[aahsac]

Mystery solved:
The good news for me is I don't have to dump any more money into this particular problem.

Good news for everyone else, yall don't have to listen to me anymore, on this particular problem anyways.

To recap the background story (I love a mystery), one owner car, owned by a school teacher(later principal), car put in storage in 1975 because of badly cracked head from overheating.

Well, the previous owner (or someone on their behalf) apparently put the leak stopper from hell into the engine back in the 70's. This stuff turned into solid metal into the block. I'm sure this stuff was advertised as being able to seal anything. It wasn't in the head since I had replaced it and I didn't scrutinize the old one. On the block/cylinder head mating surface it looked like a dark metal spot, like it had been welded and machined, if you just casually looked.

My mechanic didn't see it as he just R&R the long block. The hot vat didn't dissolve it. It's my understanding that a lot of rebuilders don't use the Oakite hot vats anymore as it is a hassle, they use a hot detergent type cleaning approach. Anyway, this stuff would dissolve just enough to turn the water black when draining the block, but hard enough to look like machined metal and hard enough to actually have to be chiseled out. Maybe someone will remember a brand of sealer that had ground up aluminum, there are some gaps in my memory of the 70's, mea culpa.

Anyway, once this stuff was chiseled out of the top of the block and flushed out the water pump (removed) area things seemed to be more normal.

The long and the short of it (will this story every end?) the car sits forever at idle with the radiator cap on or off, no overheating. It drives very nice (according to my mechanic), and he says it actually "has a lot of pep". Now, this is with a 73 head with the original 69 carb (next project).

I appreciate all the help, hopefully someone will benefit from this unusual experience.

Bottom line, bad job by the rebuilder, Blaines Motor Supply, and bad job by me (Sherlock) as I replaced the head and had the opportunity to look at the top of the block.

Stephen
Plano, Tx
Soon to be Chandler, Az



Ian.. my apologies?

 

[wallaka]

Aww...I love a happy ending.

 

[Bort62]

Ian.. my apologies?

Hardblocked... I wouldn't have even thought of that! Damn.

No apology necessary, I'm stoked you got it fixed.

 

[woodbutcher]

I do believe that the product name that you are looking for is "AlumaSeal(R)".
Leo

 

[Bort62]

I do believe that the product name that you are looking for is "AlumaSeal(R)".
Leo

I doubt it. There are actual block sealers out there that purposefully do exactly what is described.

They are used to reinforce blocks in drag racing applications. Some are marketed as "head gasket repair" and the like.

I've used a lot of aluma seal, and it wouldnt solidify like that...

Besides, they only sell it in the little tubes. That would be a LOT of those tubes

 

[l3n]

Glad you got it figured out. You ended up with one of those (hopefully) rare problems that's tricky to diagnose. Not to let your rebuilder off the hook, but that's not a common situation - they still should have gone over everything, and a judge would get you whatever spent tracking it down if they don't make it right - but at least you know that it wasn't something obvious or stupid.

The upside to dealing with this kind of crap is that you learn a hell of a lot. If you ever have another overheating problem, I bet you can unravel it pretty quick next time...