Overheating

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JD’sBarracuda

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Working on a 1969 Barracuda for an older gentleman who knows nothing about cars! I replaced all the wiring, instrument bezels, water pump, radiator, hoarse, basically everything under the hood! The car is still overheating! Top of the radiator was hot bot the bottom was cold to the touch! Pulled the thermostat anyway and checked that! Working perfectly! Pulled the radiator and checked that and again working perfectly! Pulled the water pump, all good! I noticed when I was working on this and the owner wanted to replace the intake that I could not separate it from the block! The must have used a ton of form a gasket! I’m wondering if they might have inadvertently blocked some of the Internal water lines! Any ideas guys! All comments will be appreciated
 
JD’sBarracuda said:
Working on a 1969 Barracuda for an older gentleman who knows nothing about cars! I replaced all the wiring, instrument bezels, water pump, radiator, hoarse, basically everything under the hood! The car is still overheating! Top of the radiator was hot bot the bottom was cold to the touch! Pulled the thermostat anyway and checked that! Working perfectly! Pulled the radiator and checked that and again working perfectly! Pulled the water pump, all good! I noticed when I was working on this and the owner wanted to replace the intake that I could not separate it from the block! The must have used a ton of form a gasket! I’m wondering if they might have inadvertently blocked some of the Internal water lines! Any ideas guys! All comments will be appreciated
Click to expand...
What is your definition of "overheating"! Boiling over! Spitting a little coolant out the overflow hose (overfilled tank)! Make sure the system is bled- no air pockets in the system! Using a coolant mix and not straight water! Is there a spring in the lower radiator hose so it's not getting sucked flat when running! Is it actually overheating or just a bad sensor or gauge!
 
get an aftermarket gauge on it to get a real temp reading.
use an IR gun to get real time temps at critical points.

pop the rad cap off [at a reasonable temp] and confirm coolant flow.

it might not be overheating at all, just hotter than what you think it should be or the gauge is incorrect.
 
AS the others stated we need to know more. What engine? When does it overheat? is the engine stock or rebuilt? If rebuilt do you know anything about the build? Can you post pictures?

There are many things that can cause overheating when verified getting too hot. Collapsed lower hose, tune (timing and fuel), clocked passageways, no fan shroud, aftermarket electric fans (most do not flow enough) too small aftermarket fan, etc.
 
I had a radiator that froze and swelled the tubes preventing air flow. Fought that sucker for a couple years until I figured it out. It was a new be-cool with twin fans that was in this swinger race car I bought. It was a flood car with just water and froze. I put it in My orange Duster

001.jpg


spoiler pics 663.jpg
 
Professor Fate said:
What is your definition of "overheating"! Boiling over! Spitting a little coolant out the overflow hose (overfilled tank)! Make sure the system is bled- no air pockets in the system! Using a coolant mix and not straight water! Is there a spring in the lower radiator hose so it's not getting sucked flat when running! Is it actually overheating or just a bad sensor or gauge!
Click to expand...
No, it’s actually overheating! Bottom radiator hose is the stiff flex hose so it’s not getting sucked flat
 
is it a stock radiator?
what's the fan set up?
what size are the waterpump and crank pulley?
is the waterpump new or did you only check it?
what t-stat are you running?
what's the base timing set at?

clearly define "it's actually overheating" please.
 
[1] How did you determine the rad is 'working perfectly'?
[2] Retarded ign timing causes o'heating. Since this is a 69 model, it would have come with points ign. When the points wear, the ign timing retards....
 

junkyardhero said:
is it a stock radiator?
what's the fan set up?
what size are the waterpump and crank pulley?
is the waterpump new or did you only check it?
what t-stat are you running?
what's the base timing set at?

clearly define "it's actually overheating" please.
Click to expand...
It’s all set up with original equipment as far as the pullies and fan! The water pump is new! The car starts perfectly without the choke working and after a minute it idles right at 900 rpm
 
dano said:
AS the others stated we need to know more. What engine? When does it overheat? is the engine stock or rebuilt? If rebuilt do you know anything about the build? Can you post pictures?

There are many things that can cause overheating when verified getting too hot. Collapsed lower hose, tune (timing and fuel), clocked passageways, no fan shroud, aftermarket electric fans (most do not flow enough) too small aftermarket fan, etc.
Click to expand...
Camping at the moment but will get pictures! Engine is a 340 the guy paid someone to rebuild! Start’s perfect without the choke hooked up! After a minute you can get out and the car will idle at 900rpm! I have owned numerous MOPARS! Mostly B and E bodies! Never had a problem like this with anything I worked on!
 
JD’sBarracuda said:
It’s all set up with original equipment as far as the pullies and fan! The water pump is new! The car starts perfectly without the choke working and after a minute it idles right at 900 rpm
Click to expand...
while these are answers, they contain little to no information that would be relevant in assisting you with a resolution.
 
JD’sBarracuda said:
Camping at the moment but will get pictures! Engine is a 340 the guy paid someone to rebuild! Start’s perfect without the choke hooked up! After a minute you can get out and the car will idle at 900rpm! I have owned numerous MOPARS! Mostly B and E bodies! Never had a problem like this with anything I worked on!
Click to expand...
OK, to diagnose you need:

Aftermarket temp gauge and/or IR gun. This is to find out how much and when its over heating. I'd prefer gauge as you can monitor while driving.

Vacuum gauge. To see how much vacuum you pull at warm idle

Timing light. To see if vacuum increases if you advance the timing and if any idle air adjustment changes the vacuum.

Toss the 160 thermostat and get a 180 high flow.

People ask about the pulley sizes because if mix and matched you can create an issue where you under drive the water pump.

Is the fan on a clutch and if so is it good?
 
dano said:
OK, to diagnose you need:

Aftermarket temp gauge and/or IR gun. This is to find out how much and when its over heating. I'd prefer gauge as you can monitor while driving.

Vacuum gauge. To see how much vacuum you pull at warm idle

Timing light. To see if vacuum increases if you advance the timing and if any idle air adjustment changes the vacuum.

Toss the 160 thermostat and get a 180 high flow.

People ask about the pulley sizes because if mix and matched you can create an issue where you under drive the water pump.

Is the fan on a clutch and if so is it good?
Click to expand...
No clutch fan! I’m thinking I received a bad water pump! Just fyi, can you tell me what size pullies should be on a 340?
 
JD’sBarracuda said:
No clutch fan! I’m thinking I received a bad water pump! Just fyi, can you tell me what size pullies should be on a 340?
Click to expand...
depends on the year, what accessories, what water pump, etc.

the reason we asked what the diameter they are is because you want it to be 1:1 or slightly overdriven depending on other facets of the cooling system.

JD’sBarracuda said:
Also I did check timing with vacuum gauge
Click to expand...
i'm all for olde tymey tuning, but get a damn light on it.

it's a 56 year old car, anything can be changed in that time so just saying "it's stock" don't mean a rat's patootie.

if you want help in fixing it post up some pics, get some real diagnostic tools, and do the work of determining what you actually have. we can only help so much when the information given is either incomplete or unknown.
 
Okay,,,back to post #1 .

The radiator is hot at the top but at the bottom it’s cold to the touch .
There is not any flow through the radiator then .

So,,,it’s got to be a clogged radiator,,,or a blockage in some passage in the system .
But, you said you removed and cleared the radiator of possibility .

If you remove the water pump,,,you can look into the block past the timing cover .
There should be a little flow through the pump,,,even if it’s not working .
Is the opening in the water pump clear,,I have heard of those being installed with the plastic plug left in place ?

If that’s clear,,then it must be in the intake passage or thermostat housing area ?
Water should be able to flow some even by gravity .
Take off the thermostat,,,,and the water pump .
Take a hose and run water through it .
If no internal blockage,,,then water will gush out of the timing housing .

Tommy
 
Have you taken the radiator to a professional radiator shop and had it diagnosed? When I first got Vixen, that's what she was doing. Over heating. I used an IR gun and diagnosed that the water leaving the radiator was ten degrees colder than going in. I removed the radiator cap when she cooled off. I started it up and let it idle until the thermostat opened. The radiator was so stopped up that even at idle, it puked coolant out of the radiator neck. I put a new radiator in and all was well.

You need to totally rethink your approach, IMO. Chrysler made lots of really big power muscle cars that did not over heat. I would be looking at the stock Chrysler cooling system as a template. But do what you want.
 
junkyardhero said:
is it a stock radiator?
what's the fan set up?
what size are the waterpump and crank pulley?
is the waterpump new or did you only check it?
what t-stat are you running?
what's the base timing set at?

clearly define "it's actually overheating" please.
Click to expand...
It’s a 69 340. Water pump is new purchased from classic Industries not just checked, stock radiator and no clutch fan and a 180 thermostat timing is according to specs! Starts great, runs great and idles perfectly
 
Professor Fate said:
Still no answer to "What makes you think it's overheating"?
What. Is. It. Doing? Symptoms?
Oh, I forgot the exclamation marks. !!!!
Click to expand...
Can you answer some effin questions like above ^^^^^^? I mean seriously, you come here wanting help and give so little information.
 
JD’sBarracuda said:
It’s a 69 340. Water pump is new purchased from classic Industries not just checked, stock radiator and no clutch fan and a 180 thermostat timing is according to specs! Starts great, runs great and idles perfectly
Click to expand...
again, you answer with no pertinent information.

stock radiator: is it two core, three core? has it been re-cored? is it AC or standard
waterpump: 6 blade? 8 blade? who makes it?
no clutch fan: that's cool. there's only like 100 other fans it could be, some great, some absolutely dismal
timing: according to specs? how would you know unless you put a light on it.

part of diagnosing a cooling system issue is identifying what you have and eliminating variables.

trying to help you is like playing a game of telephone and we're at the end
 
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