How to change thermostat

[euroZ06]

Sooo bought 73 charger 6 months ago, and final got around to it.

Car has 440/4 barrel from a 68. The car overheats in traffic. The radiator is brand new, timing seems to be correct. My fan seems a bit small for the car, so im looking to get a bigger one (any advice on the type/size/where to buy?). Imwas also told to replace thermostat to 160 one. I bought one at the local pepboys, and was hoping to replace it tomorrow. I was told its simple, but wanted to get some specifics. Main thing is, is it 100% necessary to drain all coolant? I dont have acccess to garage.

[A383Wing]

you don't need to drain all the coolant, only drain to just under the t-stat in the housing. I doubt the t-stat is your problem, sounds like an air-flow issue due to too small a fan blade on there. Fix what you know is wrong first, like the fan blade

[lukedukem]

What he said. Airflow issue

Luke

[euroZ06]

you don't need to drain all the coolant, only drain to just under the t-stat in the housing. I doubt the t-stat is your problem, sounds like an air-flow issue due to too small a fan blade on there. Fix what you know is wrong first, like the fan blade

Where can i get the fan blade? What brand? What size? I saw flex-a-lite fan 18 inch (blue color) at the local store, was $50... Is that good?

[ODZKing]

Depending on the size of the radiator there are several.  However, it is notable that if the engine was changed, is it possible the radiator is also too small?
What was in it before. What size is the radiator?
73 - 440 would take one of 3 blades. And I would go with 7 blades.
2863224 (18 inch)
2863216 (18.5 inch)
3462149 (20 inch)
A fellow on FABO has one with the clutch for sale
http://www.forabodiesonly.com/mopar/showthread.php?t=68468
or
http://www.ebay.com/sch/?_nkw=2863224%20fan&clk_rvr_id=680577085865
or
http://www.ebay.com/sch/?_nkw=2863216%20fan&clk_rvr_id=680586231149

[A383Wing]

stay away from those local store flex-fans.....my opinion

[euroZ06]

Depending on the size of the radiator there are several.  However, it is notable that if the engine was changed, is it possible the radiator is also too small?
What was in it before. What size is the radiator?
73 - 440 would take one of 3 blades. And I would go with 7 blades.
2863224 (18 inch)
2863216 (18.5 inch)
3462149 (20 inch)
A fellow on FABO has one with the clutch for sale
http://www.forabodiesonly.com/mopar/showthread.php?t=68468
or
http://www.ebay.com/sch/?_nkw=2863224%20fan&clk_rvr_id=680577085865
or
http://www.ebay.com/sch/?_nkw=2863216%20fan&clk_rvr_id=680586231149

Radiator is brand new, had it installed a month ago. Its big.

Can some one tell me the brand and dimensions? First link is 5yrs old.

A guy at the local car show said 18-19 inch blade is needed.

[ODZKing]

I agree, stay away from the flex.
Ha, didn't even look at the date on that.
Is it an A/C car? I'm not sure how "correct" you want to be but the last 2 digits of the fan blade are on the build sheet if you have it.
Unless you have the "Max Cooling Pkg" it is probably the 18 or 18.5.
I'd try to find the 2863216.

[ws23rt]

stay away from those local store flex-fans.....my opinion

I agree

[dual fours]

If you have some spare time, put the new and old thermostat in a pan of water (at different times of course) with a thermometer that goes past 212° and watch what temperature it opens at, it should be what they, the thermostats are set at.
What temp. thermostat is in now with the over heating trouble and does it open when it should? Wouldn't a 1968 440 take a 180°?
When you say "in traffic" I'm thinking stop an go.
Oh yes just a guess maybe your old in the car now thermostat is not closing correctly (stuck open), if I'm thinking correctly then, the water will flow continuously and over heat.

[WHITE AND RED 69]

Do you have a fan shroud? Definitely sounds like air flow issues if it only happens in traffic.

http://bouchillonperformance.com/mechanical_fans

[euroZ06]

If you have some spare time, put the new and old thermostat in a pan of water (at different times of course) with a thermometer that goes past 212° and watch what temperature it opens at, it should be what they, the thermostats are set at.
What temp. thermostat is in now with the over heating trouble and does it open when it should? Wouldn't a 1968 440 take a 180°?
When you say "in traffic" I'm thinking stop an go.
Oh yes just a guess maybe your old in the car now thermostat is not closing correctly (stuck open), if I'm thinking correctly then, the water will flow continuously and over heat.

Yes stop and go, if its moving a little then no issues.

I dont have that much time lol.

[euroZ06]

Do you have a fan shroud? Definitely sounds like air flow issues if it only happens in traffic.

http://bouchillonperformance.com/mechanical_fans

No fan shroud also, please help where do i get one?

So the 18 inch is what i need? Ill order that one on your advice

[1974dodgecharger]

I used to run with no fan shroud its not that bad per say.  At idle in 110 degree heat in AZ i would get up to 200 and get moving it goes down to 180 to 190.  My mech. Fan though was inch or inch and half away from rad.

Do you have a fan shroud? Definitely sounds like air flow issues if it only happens in traffic.

http://bouchillonperformance.com/mechanical_fans

No fan shroud also, please help where do i get one?

So the 18 inch is what i need? Ill order that one on your advice