Runs TOOOO Hot for my Liking!

Gerald Morris

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Your carburetor is lean. It is contributing to your overheating. A/C water pump is supposed to decrease water flow.
1. The crank pulley on A/C cars is always very large diameter and WP pulley is usually smaller than no A/C this makes the pump and fan spin faster.
2. So the pump is actually lower volume to circulate water slower allowing it time to cool off in larger radiator that is sitting behind the condenser and it's added heat.
3. I call BS on this because they all look the same and usually have same vane count. Result of being a engine that is out of production for 40+ years.( I know the anti-cavitation plate pumps look different, save your breath. Gerry isn't using one of these high rpm pumps)
Back to lean condition. Check plugs and try running it with choke partially closed and see if it improves. Both are free checks and free is good.
If the system pressurizes within a minute from dead cold/morning you may be looking at a head gasket.
Still leaning toward lean condition. Are we 100% sure vacuum advance is working properly? As in rate, amount and diaphragm that does not leak.

Also a 30 gallon grease barrel in plastic or metal is a nice diameter for fan shroud. Adjust the depth/length by cutting it lower down the body. Attach it to a flat piece of sheet metal with a number of tabs left in place when cutting the hole in center out. Make them long enough to get past the top ring/lip of the barrel and screw or rivet them to attach. Fold over a 1/8"-1/4" @ 45-90° on the top and bottom to give it some strength and screw it on to shroud tabs on the radiator sides

I believe you've HIT THE NAIL ON THE HEAD BRO! I can easily run around w the choke slightly closed too, AND EVEN OPEN THE IDLE SCREWS A TAD MORE, SINCE IN TRAFFIC, ONE IDLES PLENTY. I think Ray did good work on vac advance and distributor. I can measure the advance tonight, to be sure. I retarded the timing down to 7.5 degrees BTC, which eliminated WOT backfire, though acceleration still clearly fuel starved. I think its time to visit my carb guru..... I have a Carter B & B which needs a competent rebuild OR can go with the Edelbrock 1405. I have a nice intake for that too....

I also have my 1965 Imperial fan shroud. I lack the stop nuts for the radiator, but should be able to find some, and can use metal "plumbers tape" to secure the shroud into the radiator. Excepting the holes, this shroud fits perfectly.
 

70bigblockdodge

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I think Ray did good work on vac advance and distributor
Ok I did not know you had put a good unit in there, I thought maybe we were looking at old distributor.
My vote is always for a 4 bbl. Thermoquad and a 70s spread bore intake if I had a choice. Like modern fuel injection with a beautiful top end howl.
 
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Gerald Morris

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Ok I did not know you had put a good unit in there, I thought maybe we were looking at old distributor.
My vote is always for a 4 bbl. Thermoquad and a 70s spread bore intake if I had a choice. Like modern fuel injection with a beautiful top end howl.

I think I'm going to have the 'Brock 1405 rebuilt, then will use it. Its a nice, NEW carburetor, meant for manual choke, decent size but not huge.

Made GOOD progress this evening! By replacing the fuel filter after scouring out those old fuel lines with a bit of 12 gauge solid copper, and some bailing wire for tight turns, I settled the possibility that the crap from the original gas tank was clogging the lines. They actually looked pretty clean. This was the 7th fuel filter I've installed in 3 weeks, BUT, its the SECOND one after changing the gas tank Tuesday, and the VERY FIRST to have all pump clean gas running through it. The filter I removed needed it. I used my lungs to test.

After this, I dialed open the idle jet screws another half turn, and dialed down the idle itself to just 550 rpm, which was what Mathilda did so nicely with. I verified that the timing was indeed set between 6-7.5 degrees BTC. (Wish it would behave a little better, but suspect worn valve guides, timing sprockets and chain, or both. Will address around Christmas, God-willing.) With these arrangements, I took Gertrude for another shopping run, on the same busy drag I drove last night. WHAT a DIFFERENCE half a turn of the right screws makes! Engine temperature SLOWLY crept up to just 220F o my trip out. Temp cooled to about 190 when I started home, and again stayed just over 220F until I got to my trailer park driveway. Temperature crept up to 230F by the time I had parked, and shut the motor off.

This is ALMOST something I can live with! While idle jets are meant for, IDLE, a great deal of time on urban streets gets spent idling. This is when the temperature has ALWAYS crept up on any Mopar I've owned, while idling at traffic stops or creeping along at 5-15 mph in some crowded environment where engine heat and exhaust from in front aggravates thermal runaway.

IFF I can wet my cylinders with a little more petrol, it might just let them run at a stable temperature. Tonight got encouragingly close to that. I ordered another A-Team Performance 16 inch electric fan which I'll hang in front of that radiator to push plenty cool air through it when I'm in any hot urban stall. The only thing that did in my last one was that stupid sow's jumped up Datsun. For the money, these guys make the best electric fans to be had.

I also copped a 17.5 inch 7 blade clutch fan this afternoon, with thermal clutch dirt cheap. Unfortunately, I discovered my 65 Imperial shroud is 1.5 inches OFF for the upper hose divot, and thus, useless. (GRRRRR!) I'll worry about shrouding later. That electric pusher will do for that for a LOT less money or pain. That's why I love them.
 

68PK21 440.6bbl

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Now, have you any specific source expressly warning against flapper type thermostats, or are you assuming an interdiction based on this FSM quote alone?
Welp I see that we are dealing with a 383 engine and what I've read and learned over the past couple of decades specifically applies to the 440 engine thermostats, I really don't know what the difference between the 383/400/413/426 engine would be, thought they all had pretty much the same type water pump housing. I did find my old bookmark about it that was dated back 2 decades ago where they went into 'skirted' vs 'non-skirted' that activated some 'bypass' but this was all for the 440 motor so may not apply to your motor.

One thing about your testing picture that doesn't jive with the FSM and what I did different is, don't leave the thermostats laying on the bottom of the pan in contact with the direct heat source as per the FSM. use a rod and wire to suspend the thermostat in it's operating position. Also the FSM over the years spec that you try to insert a .001" feeler gauge at the certain temperature, earlier years they spec'd .003". I tried doing this and it's a PITA, everything is steaming hot and you try to hold the thermostat with needle nose pliers... BHAH! What I finally just ended up doing via information gleened from a senior mechanic back in the day was suspend the thermostat via a rod & wire in a large pot of water, bring it up to around the spec temperature, then lower and raise the thermostat in and out of the water half a dozen or more times and watch it's operation. What you are looking for is a 'Mid-point Hang', even a brand new thermostat can be be junk as by a old nutjob friend of mine (ex-Navy Jet Mechanic>ex-GE Jet Mechanic (via divorce)>QC Inspector at a USA Thermostat manufacturer), he said a lot came off the line and was boxed up as junk even back in the 70's, he was constantly fighting with management over quality control.

So recheck your thermostat's for sticking in a mid-point 'Hang', if you see one that has smooth operation for 6 to 10 time of 'dipping' from full open to full close that would be the one to use.

The flapper valve (disc to some) is to only to be used on the 6 cylinders via a later Dodge FSM illustration. (see below)

1969 Charger Coronet Dart Service Manual_7-7.Testing.Theromstat.jpg


Good luck hope you get it sorted.


Rick
 

Gerald Morris

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Welp I see that we are dealing with a 383 engine and what I've read and learned over the past couple of decades specifically applies to the 440 engine thermostats, I really don't know what the difference between the 383/400/413/426 engine would be, ....

So recheck your thermostat's for sticking in a mid-point 'Hang', if you see one that has smooth operation for 6 to 10 time of 'dipping' from full open to full close that would be the one to use.

The flapper valve (disc to some) is to only to be used on the 6 cylinders via a later Dodge FSM illustration. (see below)

View attachment 491249

Good luck hope you get it sorted.

Rick

WELL DONE AND BIG THANKS RICK!

I WILL order up a proper thermostat! Recalling the decisive improvement from this past Spring from that Mr. Gasket T-stat, I'll go ahead and get another Robert Shaw or a good clone. I saw Milodon makes one. Might do that..... Yes, having the thermostat in close proximity to the heat source doubtless queers the results. In THAT case, the inferior borosilicate pan SHATTERED within 5 minutes of my turning the heat OFF. I didn't diddle with finer measurements then being mostly interested in seeing if they worked at all. They do!

Not seeing much difference in the behavior of those poppets, I chose one and tried it last night, with some good result. I suspect increasing the amount of fuel through the idle jets while decreasing the AIR available at the idle screw had MORE effect than anything yestereve. The engine almost stabilized around 220F, excepting the tedious driveway. For such, the pusher fan makes the most cost effective remedy. Lightweight, inexpensive, CONTROLLABLE cooling makes a package hard to better.
 

68PK21 440.6bbl

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For such, the pusher fan makes the most cost effective remedy. Lightweight, inexpensive, CONTROLLABLE cooling makes a package hard to better.
Well speaking of added fans, have you had a look at the outside fins of the radiator core? I mean take a strong light or the old bulb mechanics trouble light inside the air filter trick to see how much light shine's through determining how plugged the filter is. You can do the same with the radiator to see if the fins are plugged from the outside, maybe a little hard with the fan and shroud in the way. Best results would be obtained with R&R the radiator.

I know this car has been around but if it's spent much time in the dusty AZ desert outside there still at times of the year moisture in the air (cool nights) and over time with dust blowing into everything plus add some moisture and that dust could be like cement in the fins of the radiator. many ways you could check the airflow other than using a light, reverse flow your mighty Ridged 'Shop Vac' and try pushing air through to feel if you get good flow on the others side etc. Stay away from pressure washers as you will most likely blow out or flatten the fins. A garden hose could also be used, R&R the radiator, lay it horizontal on some saw horses and just gently flow water over areas out of the bare hose end and watch where it flows out and doesn't.

.
 

Gerald Morris

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Well speaking of added fans, have you had a look at the outside fins of the radiator core? I mean take a strong light or the old bulb mechanics trouble light inside the air filter trick to see how much light shine's through determining how plugged the filter is. You can do the same with the radiator to see if the fins are plugged from the outside, maybe a little hard with the fan and shroud in the way. Best results would be obtained with R&R the radiator.

I know this car has been around but if it's spent much time in the dusty AZ desert outside there still at times of the year moisture in the air (cool nights) and over time with dust blowing into everything plus add some moisture and that dust could be like cement in the fins of the radiator. many ways you could check the airflow other than using a light, reverse flow your mighty Ridged 'Shop Vac' and try pushing air through to feel if you get good flow on the others side etc. Stay away from pressure washers as you will most likely blow out or flatten the fins. A garden hose could also be used, R&R the radiator, lay it horizontal on some saw horses and just gently flow water over areas out of the bare hose end and watch where it flows out and doesn't.

.

Amazingly enough, one can see plenty daylight through the fins all over this one! I use just my air compressor and hose nozzle, and did so when I flushed out the water jacket. Quite a rusty solution came out from that, but as always, I run the hose through the cooling system from the top, with a plug-nozzle in the radiator fill neck, no thermostat of course, and run the engine at fast idle with hose at full volume until the stuff coming out of that plug is clean enough to drink. I DO actually sip it too.

After that, the coolant remains clear clean green, as a 50% ethylene glycol solution should.

The cleanliness of the fins suggested to me that this radiator got found, cleaned up nicely, then installed to help flip the car. The flipper admitted he WANTED to keep it for a driver, but DIDN'T KNOW WHAT TO DO WITH THE CARBURETOR! THAT admission rang true enough. Many fools really need their hands broken for taking wrenches to machines they don't comprehend. But that one's ineptitude turned to my blessing, so I'll pray for the man instead.

Got temperature down to 220F running today, until I parked at home. It climbed to 230F by then. I suspect I've done about all I can with opening the idle jets to enrich the fuel/air ratio. THAT helped though, NO mistake.

Will get some "wetter" tomorrow, then visit my carburetor guru.
 

Gerald Morris

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Hmmm, nice 16 inch pusher blasting air through radiator even at stop lights, and the damned thing STILL gets hot as a $20 pistol! HEAD GASKET TIME!!!! Had to try all the other stuff first. Even got a proper thermostat in yesterday, just to be SURE about THAT shit. No good. Will get bottle of guck for temporary fix, then make a weekend date ASAP for replacing the head gaskets. Fortunately, I HAVE a head set already, as this job had been on the calendar for Mathilda for some time. At least there are no MAJOR valve or lifter issues with this one. I reckon sitting in that barn for decades just allowed the 2nd Law to have its way with the old gaskets, which are likely the original steel ones.

Stay Tuned!
 

Gerald Morris

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UPDATE! Every part I ordered came in today, EXCEPT THE ONE I PAID EXTRA TO RUSH HERE, THE DAMNED EXHAUST GAS TEST KIT!! NAPA and I together sleuthed this out to find that PAYPAL is THE CULPRIT!!!! Folks, if you HAVE TO HAVE SOMETHING RUSHED TO YOU, DON'T USE PAYPAL!!!

Aside from that, I've been cleaning off the top of the engine prior to opening the block and exposing the interior mechanism to contaminants. All the black goo appearing to be motor oil in FACT is RAT EXCREMENT!!! Thank the Lord I used my air compressor and shop vac to start removing this filth. When I got showered by RODENT FECES while using my compressor to blow out the passage under the carburetor across the valley pan, I realized that THIS MOTOR NEEDS DEEP CLEANSING FROM FRONT TO BACK, INTAKE TO OIL PAN DRAIN!

But I'll settle for replacing the head gaskets for now.

See, I shopped for and found a fellow selling what he thought was a pair of 516 heads 2 years ago. They were bolted to an old 440 in a 1966 Plymouth B body of some sort. Turned out ONE head was a 516,the other a 915. The head gaskets on that old 440 were the steel shim sorts common to yesteryear. I saw then how they CAN RUST TO POWDER when indifferently kept, and that this 440 had been subjected to this kind of failure. My current overheating problem rather forcefully reminds me of this very probability, especially coupled to rat turds, which the 440 also came adorned with. And so it goes with bona fide barn finds.....
 
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Gerald Morris

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Yep! Good Thing I HAVE medical grade masks too! My Mysophobic* Mother-in-Law made my father-in-law send us a nice big packet of hospital grade masks, surgery grade. God bless her. Hanta virus is no joke down here, and less so on the Navajo Reservation. IDK exactly how bad they have it on the Apache lands in Cochise Co., but rats just are Petri dishes full of diseases which CAN infect humans. Gloves, masks, BLEACH, HEPA filter on shop vac, and prayers.
 

68PK21 440.6bbl

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HEPA filter on shop vac
Heh you may want to disinfect your shop vac as the main contagion is the microscopic spores/dust (what'eva) that you inhale and the CDC doesn't advise to use a vacuum as you can spread the pesky little microbes. I mean I got a Space Shuttle ULPA clean room Vacuum (thank you Johnson Controls & NASA shutdown) which is above HEPA 99.97% @ 0.3 microns vs ULPA 99.999% @ 0.12 microns, but I wouldn't use it to clean up rat droppings as the ULPA filter is $250 (last I checked).

Best solution for anyone cleaning out mice/rat dropping cars is to wet everything down with a bleach solution and use a steam cleaner with attention paid to splashing the residue around, and then if it's done on your own property cleaning up the ground mess. A trip to the coin spray car wash would be advised LOL.

Even Raccoons can spread some kind of killer disease with their droppings/urine as I viewed one of these TLC/Health channel programs investigating the death of a toddler that baffled the medical staff, was that the final investigation showed that the kid died from playing and handling the backyard garden dirt and either ingesting or inhaling raccoon feces contaminated dirt which led to some kind of brain swelling reaction leading to death.

.
 

marty koirtyohann

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Greetings Moparians,

By now many of you have seen Gertrude, the 1968 convertible Newport that Chrysler apparently hastily cobbled together for export. Given how she came with a VERY OLD 115VAC plug-in coolant heater pump, I suspect this car saw duty at those latitudes above 45 degrees North. The following radiator came on the car:
View attachment 490663
This radiator lists as follows: 2898057 1968 C 22 383 MANL HTR
That's consistent with other quirks of this car; the starter relay meant for a manual transmission and the transmission cooler bolted in front of the radiator as an afterthought. Be that as it was, the hoses and clear age of the rust on the bolts all tell that these parts went off the assembly line as they now are.

Such a car wouldn't last a week in a Tucson June. Even now, after having just installed a capillary tube temperature gauge to supplement the idiot light switch in the water pump housing, I see a BAD temperature over-run up to 250 degrees Fahrenheit even when driving just 16 miles AT NIGHT with ambient temperature of just 74 degrees. This cruise should have rolled along at 190 F in Mathilda.

WHAT causes such a drastic heat-up?

I speculate that both the radiator and the on-AC water pump fail miserably to cool this engine in this environment. I flushed the coolant last week, and filled the radiator to the prescribed 1.25 inches below the filling neck with a 50% ethylene glycol mixture. I put a new (NOS) brass poppet thermostat in after suspecting at first that the Mr. Gasket Robert Shaw clone might have stuck. I've seen some flow after warming the engine up, so I figure the stat is opening, BUT....

Is the coolant flowing ENOUGH?

The water pump housing doesn't permit any extra temperature gauges, so I got clever and bored out a Dorman thermostat housing of this sort:
View attachment 490664
Its VERY EASY to drill and tap for 3/8 inch NPT into the flat spot facing diagonally out. I did so.
View attachment 490665
The capillary probe doesn't block or interfere with the thermostat. I made SURE of that before tightening down, taking some pains to rotate the thermostat to assure that it opens on the side opposite where the probe enters the housing. Admittedly, until the stat opens, the temperature reading from this arrangement might lag a LITTLE behind what the block coolant temperature is, but it doesn't lag much. This engine warms up to 180 F in under 5 minutes at fast idle.

My questions to the More Experienced Moparians are:

1.) Should I shop for a more voluminous 22 inch radiator? While I originally hoped to keep this one in service, I now suspect that even in brand new condition, this radiator will not cool well enough in Tucson traffic, even after sundown.

2.) Mathilda ALWAYS ran the higher volume water pumps! These were originally designated for use with air conditioning, but I suspect they got installed on anything which had to cool rigorously. Towing comes to mind aside from AC... I have the identical straight 6 blade fan Mathilda ran coolly with her first summer serving us. The radiator WAS a better model, meant for Hi Alt, AC and auto trans, despite being a 22 inch radiator. If THAT one didn't leak so much, I would never have opted for aluminum radiators. But it does leak.... Should I try a high volume water pump?

3.) The bottom hose is molded, lacking a spring to hold it open. I prefer sprung hoses. I can easily cannibalize Mathilda of her Gates Green Stripe right now, if warranted. How much could a partly collapsed lower hose contribute to heat runaway?

4.) While TIMING has occurred to me as a possible source of runaway overheating, right now, I'm at ~ 9 degrees BTC. This might cause detonation, but usually, RETARDED timing is more apt to cause overheating, right? This motor should be at 7.5 degrees BTC according to the FSM. I can bump it back to that easily enough.

I probably will start tomorrow with pulling the thermostat, and noting how long it takes this engine to reach various temperatures. I really don't expect this to have much impact, but want to eliminate the possibility ASAP, in order to then get to solving the more basic, inherent problem.

I suspect this will be a combination of undersized radiator and water pump, but if I AM missing something BASIC and CRUCIAL here, I would thank folks for telling me.

Just trying to Be Cool....
do u have a fan shroud on it ? its important to maintain the right temp . then what thermostat r u runing ? is it a 195? pr a 185? if its a 195 it too hot tye old b/rb was ment to rin no more than a 185 . if everything in tye radisator is clear & free flowing u may have t gp to s high flow 160 thermostat . also r u udeing s fan clutchh? all is needed to make it run @ 195-200
 
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