LocuMob
Fluid Technician with a hat
I've had new ones that sealed like crap, had to use too much RTV before it would seal. Got another new one, worked fine.
My 440 GT boils after I switch the engine off
- Thread starter Wollfen
- Start date
Wollfen
Old Man with a Hat
Yes, well RWC is not saying it will leak, he is saying it sucks air. Mine isn't leaking at all, I'm not losing any coolant around it. The idea that it will produce a large stream of bubbles in the radiator is what I find surprising.
LocuMob
Fluid Technician with a hat
I was just saying mine was troublesome, I see how I could confuse people on that, or get confused myself!
I use the billet aluminum one from 440 Source. I had problems with the stock ones leaking. A little pricey but I never had another problem.
LocuMob
Fluid Technician with a hat
That's what I got for my engine build.
Those OEM ones get very pourous and just start leaking and/or sucking air. And with the compressor and brackets right in the way makes it a pain in the *** to replace.
polara71
Old Man with a Hat
Ive never had a problem with one going bad . Thats 33 plus years of driving nothing but a pentastar
Wollfen
Old Man with a Hat
I pulled the head on the drivers side first, note the moisture corrosion on the surface of No8, strange.
70bigblockdodge
Old Man with a Hat
346 head was the only BB head I have ever had with a crack. Mine was in that section where your gasket is not stuck between the two siamese exhaust ports. I still say it's your cap.
Wollfen
Old Man with a Hat
How do you get a stream of bubbles in your radiator when the cap is off and the engine is running? How is it the cap?
70bigblockdodge
Old Man with a Hat
Easy if the center two exhaust ports( the hottest spot in any big block is boiling the coolant there even though the coolant out at t- stat is only 195 the boiling or formation of steam at that point releases the oxygen from the coolant stream of bubbles carried into the radiator. Cavitation in the eye of the pump (low pressure area) is forming steam in the same way but at a lower temp because of lower pressure at center. You pressurize the system and no water is boiling at anything less than 256° . Your system is boiling, has entrained bubbles, and pukes and rumbles too much.
If it has big giant bubbles and foam like kids bubble solution them maybe I will buy a internal leak. Big blocks have 34 head bolts and almost never crack let alone leak water. It just my opinion from what was mentioned. The only head gaskets on a BB I have ever seen have a problem is ultra high compression ratio and old rusty 40 yo originals.
If it has big giant bubbles and foam like kids bubble solution them maybe I will buy a internal leak. Big blocks have 34 head bolts and almost never crack let alone leak water. It just my opinion from what was mentioned. The only head gaskets on a BB I have ever seen have a problem is ultra high compression ratio and old rusty 40 yo originals.
IDK... I would have really liked the combustion gas test at this point. If even a little coolant got into the chamber I would expect it to be shiny and steam cleaned. It's off... may as well check it over carefully before going back together.
rags
Senior Member
the area where the soft head gasket material didn't adhere is suspicious in itself. flip's dead nut right above. any evidence of steam cleaning in the combustion chambers or piston tops indicates a leak. checking for combustion gases would have eliminated a range possibilities. this seams more like a circulation issue though, more inline with post #73, with the engine in fact NOT skipping and no coolant smell from the exhaust on first start-up when over night cold.
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Wollfen
Old Man with a Hat
Yah the head gasket material doesn't look right to me. The idea that the radiator will show a stream of bubbles when not boiling because of the radiator cap just doesn't make sense to me. If that were true you would see it in any engine that you ran for awhile without the cap on. I haven't ever had that happen in any engine. Seeing that the head gasket isn't sticking in multiple places still leads me to believe that some high pressure air was pushing into the coolant chambers somewhere. I will be pulling off the other head too. I thought about it and decided not to buy the gas test system, the fifty bucks was hard to justify. I am not a workshop, I doubt I would ever use it again.
Im going to check the heads and block for flatness again, if I find nothing obvious I will probably buy a crack test kit which is more practical for me. Always good for checking parts that are bought and sold.
Im going to check the heads and block for flatness again, if I find nothing obvious I will probably buy a crack test kit which is more practical for me. Always good for checking parts that are bought and sold.
rags
Senior Member
those are the lines that tell the story. if it overheats with the thermostat out, it's a circulation problem. it would have to be a big crack to make that much heat with no thermostat. plus there would be other signs. problem would be prevalent with the engine running. coolant in the oil. something. was the block media blasted? substrate left in the block itself preventing coolant from circulating to the back?
70bigblockdodge
Old Man with a Hat
What kind of head gaskets did you use?
The only thing that is not suspicious about that is that there is no cooling passage there, seems if it was leaking it would be leaking down the side of the block. Maybe the other head will reveal something for all the effort.
I'm really sorry nothing has presented itself yet. I'm going to run down a few things here, I know some of them may not be as useful to you as they might be to someone else who reads this.
Since your heads are off, you're doing what you can at home with your plan. Maybe the other head will show something, look close at the exhaust ports too JIC you find one of them has cleaned itself from a leak. It would be unusual, but not impossible to have tiny combustion leak that did not put coolant back into a cylinder. So if nothing is found assume/hope the head gaskets are solving the issues and if everything is flat reassemble and hope it proves out.
Once she's back together, and you're testing/rechecking her again... It is a funny thing how we can find air in an open system that leads us to all kinds of false conclusions. Sorry Gary, I would have offered you a block test kit on loan, but I figured you could find one for close to $40 and that round trip shipping would be close to $20 so I didn't think it made much sense. You are correct, a home user would get little use out of one, but it would be cheaper to own it than to pay someone else to do it for you. I think that will be off the table for the rest of whatever happens for you now.
This is a worthwhile $30 tool for anyone who has fought to get the air to bleed from a cooling system...Amazon.com: Lisle 24680 Spill-Free Funnel: Automotive
The advantage of these funnels is they allow you to keep the air out of the radiator that otherwise you cant avoid while testing when open... if this thing is giving bubbles you are either bleeding air or have something making the bubbles for sure... just be careful when the thermostat first opens or if the engine starts to boil the coolant... the coolant will still get pretty violent (steam). They also help you keep the coolant off the ground which may matter to you. I have had one of these in my collection since the early 90's and I would still buy another if I needed to (I'm now a home user too).
If you pull a thermostat, always break the center (valve) out of your old one and reinstall the plate as a restriction... a completely missing thermostat allows too much coolant flow and can be the cause of overheating all by itself when driven that way. At idle, for testing only, less likely to be an issue. For small time racing or street builders who want to run without a thermostat: Moroso Water Outlet Restrictor Kits 63440
Sucking air, without leaking coolant is a strange, but not entirely impossible situation... It should not be very much air once the engine warms up (parts expand and seal better)... or you would have a leak. The biggest importance to allowing air into a cooling system is the thermostat and the coolant sender must be completely submerged in coolant to operate. To assure that my thermostat will bleed air, I make sure it has a built in air bleed...
Or I drill one with the smallest bit in the index...
If you are concerned that you have the "sucking air" problem... part stores should have little bottles of cooling system florescent dye available... with a pressure tester (loaner tool?) you should be able to cause the dye to come back through the air leak... The dye pops pretty good with a blue or black light. If the engine is cold... do not pressurize the system to the maximum cap pressure or you may cause leaks to occur.
There are no automotive cooling system flow gauges that I am familiar with... a quick search turned up this Miller(Mopar) tool, but I bet it's application is more related to HVAC functions... judging by the hoses... maybe someone else can tell me about it's application.
If you had very little flow, like a ruined water pump impeller, you could feel the top and bottom hoses during a warmup cycle... once the thermostat opens the bottom hose should get close to the top hose temperature pretty fast (by feel). Unfortunately improper flow is going to be more difficult and a IR temp gun is a good and cheap tool for this($20ish).
The temperature drop at the radiator, top and bottom hoses is all you really can do to diagnose flow. GM's crossflow radiators were a little easier to look inside of to see the top few tubes, but still not a very good visual check. Also immediately after a 50ish MPH run... use the IR gun to check temps across the center and edges of the radiator (you want a warmed engine and a air cooled radiator) biggish differences at the center tubes can affect thermostatic clutch fans. The problem with these diagnostics is they are affected by both coolant flow and airflow... so make sure you have the easy airflow issues covered (fan shrouds and clutch fans). BTW in reference to the MotoMeter... you have a coolant temperature gauge... not so useful.
I'm sure there will be some folks adding to this or providing alternate thoughts... cooling performance issues can be a PITA to nail down, but only because of limited testing ability.
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Ripinator
Old Man with a Hat
Gary: Any updates regarding this very frustrating problem? I feel like I'm as stressed as you are. . .
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