Engine acts like there is no thermostat.. out of ideas

[T16]

Here´s the problem: Last summer while driving on the highway the engine temp never climbed over 150F (65 Celsius). When in colder weather (round 50F) I find it very hard to keep the heater warm.

I know you´re all going to say "Change the thermostat".. And i´ve done that.. TWICE   (180F thermostat)
My engine acts like there is no thermostat.. and I´m out of ideas.

Ok its not a big problem because the Charger is only driven mostly in the summer.. but it bothers me when engine is not running at correct temp at highway.
While citycruising temp climbs up to 180-230 depending on summerweather.
Engine has always acted like this since I put it together.
I´ve searched the pumping house if any coolant could leak past the thermostat but cant se any wrong there..

I have no idea how a stock cooling system for a 72 should look like. All I know is that the 72 overflow bottle is hard to find
I´m running a fan clutch (but fan always spins??) and no owerflow bottle

Any ideas..?

[FLG]

Hmm that seems very cold!

First, are you sure the temp gauge is correct?

Secondly, take the termostat you removed and put it in a pot of water, see when it opens up (water should be boiling when it does)

Even with NO thermostat on a cold day my motor used to run at about 150 the lowest...outside temps in the low-mid 40's

[T16]

Oups.. of course i meant 150F.. not 65F (we use Celsius over here) 

Anyway.. temp gauge (aftermarket) have been tested outside of car.. and i´ve also boiled the second (new) 180F thermostat.

[flyinlow]

First ,call Al Gore and tell him you have a cure for global warming, a V8 that makes no heat.
His number is 1-800-dip-sh*t.


I agree with FLG.

Are your radiator and heater hoses getting hot? If your temp sensor is scaled over and your heater core is plugged . you think the engine is not getting up to temp and no hot water flow thru the core.

Clutch fans spin all the time. They just spin harder when the airflow thru the radiator is hot ,if thermostatic clutch.

They won't let you on a dragstrip without an overflow bottle, but you can drive aound all day on the street without it. They are a good idea to have .

[b5blue]

Replace the sending unit and check all grounds to motor first. 

[RCKSTR]

Are you burping the system with the heater on after you change the thermostat? Could be an air lock caught in it.

[charger Downunder]

Have you got the big pulley or small pulley on your water pump.Do a swap and try it.

[Rayzor]

I was wondering where you have the temp probe. Is it in the side of the block or up on the water pump housing. If its down low in block its getting hit with the water fresh cooled out of the radiator. If its up on the water pump housing, then it should read water temp after cooling the heads showing your true temps.

[TylerCharger69]

You telling me that the heater doesnt seem to get warm enough tells me that it isnt a gauge issue....I'm leading toward an air lock in the system as posted above by RCKSTR.  I found that jacking up the front of the car while filling  (and running) can burp out the air.  Basically allows the air bubbles to travel upward to the radiator fill inlet.  I dont think an overflow would solve this problem.  Or...on the other hand, there may be a blockage somewhere.  It is possible, however that you have a scale build up on the temp sending unit, but I'm leaning toward air in the system.   What engine is in it by the way,  and is it stock?

[john.v]

any photo's of the engine?  like to see the hoses

[flyinlow]

What engine? 

Disconect the heater hoses at the engine . Run water thru the heater core with a hose. Dont force water thru ,city water pressure can be 50-60 psi. Should flow easily. If not heater control valve is bad or the heater core is probably restricted.

Look in nipples on the engine , should be open.

You said temp guage showed 150*F, fully warmed up ,with two different 180* thermostats on a cold day (40*F).

I would think temp the guage is inaccurate.

You said 180-230*F in the summer. 230 is too hot ,if your guage is reading 30* off you engine is really hot at 260*

Check coolant flow past radiator cap neck with a warmed up engine at a fast idle. Should be a decent flow.

You can drill a 1/16 hole in the thermostat to help burp the cooling system.

[flyinlow]

heater hose pic.

[flyinlow]

no pics today

[T16]

no pics today

Thanks guys.. Will get back with more info tomorrow.. Just spent the day changing turbo on my daily driver.. Need to get some sleep 

[T16]

Dont know if it says much:

Engine:
383 cid
Crower 271HDP cam (Duration: 271º Lift: .486)
Edelbrock DP4B intake
Holley 750 vac
Mopar electronic ignition
516 closed chamber heads.
1-3/4" headers

Like I said.. I´ve had my doubts the temp gauge was faulty. So i tested it outside the car. It works. The sender unit mounted on the original position on the pump housing.
When i drove the car this fall (before puting it to wintersleep) it was below 40F outside. I had to put a pice of cardborad to cover upp 2/3 of the radiator. Even then temp never got over 140F.. so something must be wrong

Maybe air trapped..?

Have you got the big pulley or small pulley on your water pump.Do a swap and try it.

Been thinking about this.. dont know what pulley i´ve got. Also.. isn´t there 2 types of waterpumps..? On for AC-cars..?
Pulley measures aprox. 6.7" diameter. Big or small one 

It will be at least a copule of months before I can drive the car.. since we got 17" of snow here 

[maxwellwedge]

Looks like it was an A/C car with no A/C now. For starters I would take that heat control valve off and run the hoses from the pump right to the nipples on the firewall.

[b5blue]

And send it to me! 

[Musicman]

Does the engine reach full temp when your just sitting there idling in the driveway?

[charger Downunder]

Dont know if it says much:

Engine:
383 cid
Crower 271HDP cam (Duration: 271º Lift: .486)
Edelbrock DP4B intake
Holley 750 vac
Mopar electronic ignition
516 closed chamber heads.
1-3/4" headers

Like I said.. I´ve had my doubts the temp gauge was faulty. So i tested it outside the car. It works. The sender unit mounted on the original position on the pump housing.
When i drove the car this fall (before puting it to wintersleep) it was below 40F outside. I had to put a pice of cardborad to cover upp 2/3 of the radiator. Even then temp never got over 140F.. so something must be wrong

Maybe air trapped..?

Have you got the big pulley or small pulley on your water pump.Do a swap and try it.

Been thinking about this.. dont know what pulley i´ve got. Also.. isn´t there 2 types of waterpumps..? On for AC-cars..?
Pulley measures aprox. 6.7" diameter. Big or small one 

You have the big pulley  try the smaller one the pump will spin faster.Looks like your car has a/c. I would say you have an a/c water pump and a non a/c pulley.The pump is turning too slow.

[Tilar]

Have the heads been off of this engine recently?

Since it seems like you've checked everything else, It almost sounds like the head gaskets are either A) on backwards only running water through the front part of the system which would keep that part really cool and in turn keeping the rear of the engine with not enough cooling flow or B) the head gaskets have way too many or too big of holes allowing water to come through the entire length of the heads in essence not allowing the engine to create enough heat.

The heads and gaskets should be designed to flow water through the block with the majority of the water coming in through the rear of the heads and throughout the whole head and then back out through the front. If the gaskets are allowing a lot of water to transfer throughout the entire length of the head chances are your water pump would pump enough volume to not allow the engine to heat up.

I believe that the holes are in the block and heads and should be covered by the head gasket with only small holes going through the gaskets. If someone has been in there recently they may have drilled out the gaskets thinking that it would help more coolant flow, which it will but it will also give you the same scenario that you are experiencing. This would be good on the drag strip but not on a daily driver. I guess it's possible that if the engine hasnt been apart that the head gaskets could be deteriorating around those holes allowing more water to flow.

[T16]

Yeah it´s an AC car.. but now AC removed.
I´ve had this engine apart a few years ago.. And just ordered a new Chrylser BB watrepump from my local store at that time.

Head gaskets are steel shims kind that a bought new on ebay..
Also bought a heater control valve, but dont think it´s right for my cars. But I can turn heat on and of so i´ve sticked to it so far

[firefighter3931]

Been thinking about this.. dont know what pulley i´ve got. Also.. isn´t there 2 types of waterpumps..? On for AC-cars..?

Pulley measures aprox. 6.7" diameter. Big or small one 

Yes, there are 2 different waterpumps but only 1 pulley. Yours is the correct size (6.78 inches)

http://www.bouchillonperformance.com/BPEpulleys.asp

The thermostat ultimately controls the minimum engine temp. If the temp guage is accurate then that is what the thermostat is opening at. Use an infrared heat gun to verify your temp readings.

Increased temps in town (traffic) is a low speed airflow issue across the rad core. A fan shroud will help in this area. 



Ron