Could my 340 block be filled?

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gtgto

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My car has run hot since I got it about a year and a half ago. I have not put many miles on the car and I'm limited to short trips. My car looks as if it had a roll cage in it at some point of its 47 year life. I see 4 holes in the floor in a square shape on both the drivers and passengers side right behind the front seats which makes me think a roll cage was present.

I am waiting on a new radiator since the one I paid good money to have re cored sprung a leak the other day. I will be bringing it back to them to have them fix what they for some reason did not fix the first time.

If my new thermostat and radiator do not get my factory temp gauge to hold steady around 1/2 way or just below what else can I pursue as the cause of running hot?

My buddy is convinced my car was driven hard and suggested the block might be filled with epoxy or some kind of cement that drag racers use. If I have no luck is a tear down in order or could I find out some other way?
 
Pull the block drains on the side of the block and see what is in there
 
Pop an expansion plug or two. Then you can get a good look.
Get a non-contact or infra red thermometer, then start checking.
 
There are a multitude of causes for overheating.....on my list a filled block would be pretty near the bottom.

Water pump vanes eroded away
Bad thermostat
Bad rad
Hoses collapsing
Electric fans actually blocking airflow through the rad
Electric fans wired to run the wrong way so they act against the mechanical fan
Bad mechanical fan clutch
Mechanical fan too far away from rad
Crappy flex fan
No fan shroud
AC condenser in front of rad blocking airflow
Engine running to lean
Timing not set right
Plugged exhaust
Rad cap not holding pressure



You get the idea......
 
There are a multitude of causes for overheating.....on my list a filled block would be pretty near the bottom.

Water pump vanes eroded away
Bad thermostat
Bad rad
Hoses collapsing
Electric fans actually blocking airflow through the rad
Electric fans wired to run the wrong way so they act against the mechanical fan
Bad mechanical fan clutch
Mechanical fan too far away from rad
Crappy flex fan
No fan shroud
AC condenser in front of rad blocking airflow
Engine running to lean
Timing not set right
Plugged exhaust
Rad cap not holding pressure



You get the idea......
That is quite a list. I have a number of them already taken care of....Engine has new water pump installed when I did the timing chain not long ago. Car has original fan, fan clutch and radiator shroud installed. I most recently installed a spring in the lower radiator hose to eliminate the possibility of it collapsing.Engine is matching number to the car and appears to look and sound stock so I have the timing set to around 10 BTDC at 900 RPM's. I do not have any way to check fuel A/F mixture but the original AVS did go through an extensive re manufacturing job about a year ago. The rad cap is newer as well....the car has factory 3.91's in the rear so the engine does turn high rpm's on occasion. I'm praying the new thermostat and radiator is as far as I have to go. I'll let you know how I make out.....
 
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"If my new thermostat and radiator do not get my factory temp gauge to hold steady around 1/2 way or just below what else can I pursue as the cause of running hot?"

To me the factory temp gauge is suspect. My 440 Demon shows 3/4 on factory gauge which has a new sending unit good grounds to the dash etc, the auxiliary VDO gauge and the Sniper EFI handheld will be showing 185 which is the thermostat I'm running. I'd put or at least temp install an aftermarket gauge to verify before hitting the panic button.
 
After market sending units and a stock gauge can give you a hot reading. I have a 64 Fairlane that always seemed
to run hot on stock gauge. Got an original sending unit at a wrecking yard years ago. It always runs cool on the stock gauge and I haven't had any over heating issues. It has a shroud and stock fan.
 
If the block is filled with Hard Block or some other form of cement, you won't be able to remove a expansion plug from the side of the block!
 
As was stated above. Pull the pipe plug block drains if you want to know for sure. You might have to probe around a little to find coolant as they tend to get sludged up.
 
I've said it before, and I'll say it again. Buy an Infrared Thermometer. They aren't that expensive, and you won't believe how handy they are. You can aim at the thermostat housing and see exactly what temp the engine is at.
 
I've said it before, and I'll say it again. Buy an Infrared Thermometer. They aren't that expensive, and you won't believe how handy they are. You can aim at the thermostat housing and see exactly what temp the engine is at.

x2. In many blocks, pulling the drains in an un-rebuilt block will just leave you with a passage blocked by casting core sand. These IR guns are cheap and great diagnostic tools for these situations. Hit the block, hit the water outlet, top and bottom of the radiator... You'll find the hotter vs cooler areas quickly. It could be something like silicone stuck in a head passage, or a dead mouse (I traded a car because of missing that one), or a bad gage.
 
What exactly makes you think it is running hot? (other than a 50 year-old "gauge" that was never accurate even from day one?)
 
verify it's running hot factory gauges are just functioning ornaments .
I plan on it hopefully this weekend. I do have an analog gauge and I'm also looking to purchase an infrared thermometer to add to my tool collection.
 
Put the new radiator in and a new thermostat. The new thermostat didn't come with a new gasket so I assembled it and used some permatex to make a gasket. Didn't turn out to good as it was wet after running the car for a while. I got a gasket they had in stock at Advanced Auto. Fired up the car and drove it for a little while, maybe 10 miles or so and the factory temp gauge went up to like 3/4. I didn't install the analog gauge I have on hand yet to see the number though. Drove past it and was in the process of taking my car home and she stopped running while driving.....Lost spark for some reason and pulled off the road. Popped the hood and just looked and saw nothing obvious. A guy pulled up and offered assistance which was nice of him. I told him I was going to let it cool down and try to fire her up. I just checked connections and let the car sit for about 10 minutes or so. After that I dropped the hood and got in and turned the key. She fired up and I was able to limp her home without a visit from the AAA flatbed. The car is frustrating me to no end. I'm not sure if its the orange electronic ignition module I bought that is causing the latest issues but I've heard a lot of bad things about them. The upper radiator hose felt like it had some pressure in it but not that much. I am going to try to bypass the heater core and install the analog gauge to see if it helps at all. That's my next step. Oh the pain.
 
until you find out what temp the engine is running we can't help with the heating problem as far as your next problem a dirty bulkhead connector will cause the very problem and yes it can be intermitted .
 
I have run the orange box on several cars with only one failure. It went intermittent, as you described and would just quit. Cheap insurance is to carry another one, and yes, be sure the bulkhead connector is internally clean and that the connections are tight. It too will cause issues.
 
I once had a faulty coil that caused those symptoms. When it got hot, it stopped working. Cool off for even a few minutes, and the car would run again for a while.

But you really need to fix just one thing at a time.
 
I have run the orange box on several cars with only one failure. It went intermittent, as you described and would just quit. Cheap insurance is to carry another one, and yes, be sure the bulkhead connector is internally clean and that the connections are tight. It too will cause issues.
Hopefully tomorrow i"ll get some garage time....Had the inlaws over for dinner tonight which is always a fun time......NOT....I did take a look and my fan shroud looks to be warped and there's about a 1/2-3/4 inch gap between the shroud and the radiator...Could that be a potential cause for concern?
 
I've said it before, and I'll say it again. Buy an Infrared Thermometer. They aren't that expensive, and you won't believe how handy they are. You can aim at the thermostat housing and see exactly what temp the engine is at.

Why the heck should ANY of these guys around here do ANYTHING that requires common sense? An infra red thermometer is what, a whole 20 bucks? Why in the WORLD would anybody have to spend any money on anything? Someone should just wave their magic wand and solve his problem.
 
Hi, you said that you are using the factory gauge? If so, what part number sending unit do you have installed? I will tell you from experience that the ones that are sold at most parts stores are the wrong OHM's! This is because of an interchange discrepency that happened years ago and was never fixed! The most common sensor sold for our A-bodies today is a Standard brand "TS17". This is the incorrect sensor! The correct sensor part number is "TS205"! I was in parts for 19 years and found this error by specing out the sensors in an old Blue Streak catalog. Hope this helps! Lee.
 
Why the heck should ANY of these guys around here do ANYTHING that requires common sense? An infra red thermometer is what, a whole 20 bucks? Why in the WORLD would anybody have to spend any money on anything? Someone should just wave their magic wand and solve his problem.
LOL, aint it the truth. I use mine all the time.
 
Hi, you said that you are using the factory gauge? If so, what part number sending unit do you have installed? I will tell you from experience that the ones that are sold at most parts stores are the wrong OHM's! This is because of an interchange discrepency that happened years ago and was never fixed! The most common sensor sold for our A-bodies today is a Standard brand "TS17". This is the incorrect sensor! The correct sensor part number is "TS205"! I was in parts for 19 years and found this error by specing out the sensors in an old Blue Streak catalog. Hope this helps! Lee.
 
I'm pretty sure I have a TS17 installed and it wasn't long ago that it was installed. I don't see anything online about the TS205 fitting or being for my car though....I picked up an infrared thermometer on my way into work today so later I will see what temp I'm running at when the gauge is up to 3/4.
 
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