360 overheating -please help

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73dart360

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i have a 1973 dart swinger -I bought off Ebay the guy said it has J heads and he did a lot of work on them ?? who knows if this is the truth the motor seems strong though,since recieving the car the temp would not stay below 230 it would rise slowly the engine combo is 1978 360 9.5 to 1 comp cam Hyd
.510 duration at .50 intake 240 exhaust 246 -lobe lift .3380 Exh .3400
lobe seperation 110.0 dont know what pistons or any internals -airgap intake 1" spacer , headers,flowmaster,aluminum radiator,16" electric fan 2150 ,the stock fan is gone,cfm ,edelbrock hi volume water pump,no thermostat, holley HP 750 DP,TCI super street fighter 3500 stahl 8/3/4 with 4.10 posi,904 built , on the highway cruising at 50 mph temp seem ok anywhere in town the temp guage rises like flood water i used an infa red heat guage it was rising up to 230 and beyond if i let it. the car has not boiled over but when i see the guage rising i turn it off ,ive had the car for 1 year sunk a small fortune in it and probably only have driven it for 1 total hr due to getting hot i dont want to blow it up,i am not mechancally inclined but i do listen.
 
Get a 185 degree thermostat and a new rad cap that holds 16-18 lbs PSI.Recheck the timing and make sure the total timing does not exceed 36 degrees.Make sure you have a 50/50% water and anti-freeze mix.Does the tranny cooler lines go into and out of the rad,and to a nother cooler? if so,seperate them and do not run the lines into the rad,run them to a seperate cooler,the biggest you can find,Mrmoparteech
 
73dart360 said:
i have a 1973 dart swinger -I bought off Ebay the guy said it has J heads and he did a lot of work on them ?? who knows if this is the truth the motor seems strong though,since recieving the car the temp would not stay below 230 it would rise slowly the engine combo is 1978 360 9.5 to 1 comp cam Hyd
.510 duration at .50 intake 240 exhaust 246 -lobe lift .3380 Exh .3400
lobe seperation 110.0 dont know what pistons or any internals -airgap intake 1" spacer , headers,flowmaster,aluminum radiator,16" electric fan 2150 ,the stock fan is gone,cfm ,edelbrock hi volume water pump,no thermostat, holley HP 750 DP,TCI super street fighter 3500 stahl 8/3/4 with 4.10 posi,904 built , on the highway cruising at 50 mph temp seem ok anywhere in town the temp guage rises like flood water i used an infa red heat guage it was rising up to 230 and beyond if i let it. the car has not boiled over but when i see the guage rising i turn it off ,ive had the car for 1 year sunk a small fortune in it and probably only have driven it for 1 total hr due to getting hot i dont want to blow it up,i am not mechancally inclined but i do listen.

If you're not running a thermstat you could be overflowing the system and not giving the glycol mix time to disipate it's heat through the rad. The thermstat also acts as an orifice to control flow.
 
You didn't say if you'd taken it to a radiator shop. My buddy had a new radiator built for his 1917 "bucket" with a 360 and fought the same type of problem. He finally gave up an took it back and found some silicon had plugged the new radiator. They cleaned it out and never overheats now. Good luck.
 
hey guys thanks so much for the responses ,there is only 1 radiator cooler i will put a thermostat back in tomorrow ,i had 1 in previously it does have an 18 to 20# radiator cap i had to have it for the track,i did remove the stock fan and shroud and installed a electric fan do you think i robbed air from cooling the motor
 
i forgot to say i have a 3/4" reducer instead of a thermostat should i still switch to a thermostat?
 
You need to install the stock fan shroud and 5 or 7 bladed fan with the viscous clutch. You might also want to install a pusher fan in front of the radiator if the stock fan/shroud isn't enough. Also like everyone else has said, install a 185 degree thermostat. It's possible if your 360 has been bored .040-.060 inch oversize that it will run on the hot side. Additionally, run a high capacity trans cooler, with the inlet side (from the trans) to the cooler, then back through the radiator prior to running back to the trans. Make sure your cooling system is in good shape, timing not excessively retarded and you should be able to keep it at or under 200 degrees at idle.
 
ONE step at a time - install thermostat FIRST to slow down the flow so it has time to cool in the radiator.
Are you running stock pulleys? and not an undersized crank pulley - as that reduces flow at lower RPMs and will cause a cooling problem too.
 
FYI, my 360 had a new 2 row radiator and was still hitting 210+ in traffic. I took it out and had my rad guy put a 3 row, with 1/2 " tubes on 3/8" center(stock is 1/2" on center) and dimpled tubes to slow the water down to cool it more in the rad. in traffic, now it only hits 185, and maybe 190 at most.
 
My 360 in my Scamp would stay nice and cool on the highway or pretty much as long as I was moving, no matter how slow I was moving. If I got in traffic on a hot day or went through a drive through or something it would heat up. I had a good thermostat, good water pump, and a "good" stock radiator that was the factory 318 radiator. I put in an aluminum radiator and a tranny cooler, and now the car runs almost cold and never heats up. Simply put, your radiator might not be up to the task of cooling your larger, modified engine. Mine wasn't. That being said, all the posters have given you good advice. All you have to do now is sort it out and get your car running cool.
 
On a motor like that, your initial timing will need to be 12-16 degrees, total no more than 36 degrees. Because of the cam overlap, some unburnt gas is going into the exhaust port and igniting there, raising temps. I actually run 22 degrees initial and 34 total in my 440 dart, and it runs cool. Good luck! As the gentleman above said, ONE STEP AT A TIME!
 
Lots of good advice here. I would start with the no-buck and low buck stuff first. Then on to the $$$ solutions.
 
To everybody that responded i greatly appreciate your advice like i said im not mechanically inclined but i listened well. I jut ordered from year one-a 3 core factory radiator and a factory fan -also ordered a 180 degee themostat,and will have my mechanic set timing at 34 degrees,I am also bidding on an original fan shoud which the car has never had since i recieved it. i will post how it turns out ,i think she`ll be running cooler ,year one said 3 weeks before i get the radiator.
Thank again :thumblef:
 
Sometimes, all can be well, and an outside factor bites you. Mine was a 383 Swinger I built and sold. I sold it and part of the deal was a cam swap with a used one he had. So I did the work, drove it around, all was fine. It didnt make it the 20 miles to the new owner's house because it was overheating. He ended up fishing a dead mouse out of the water outlet on the lower tank (yuk). Now I put tape over all the inlets and outlets when the radiators come out....lol...live and learn...
 
Overheating resolved -I bought a new 3 core radiator and bought a fan shroud from one of our members then installed 180 thermostat -perfect the hottest it got on a 90degree day was 190 thanks guys now ican finally drive it and not worry-
 
Glad you got it working. Comments made about timing are very relevant and should be kept in mind.

For example, in my case this is what happened with my 360/300 Commando crate engine:

1. I timed it using my regular Sears timing light to 36 total as best as I could.

2. Mechanic said it was off timing. He had a better light (which when he showned me all it did, I did not even get it, duh). He retimed it. It ran 185 all the time, 175-180 in winter. But it lacked power and acted like it was running too lean (just sounded that way - no Grrrrrrrrrrrrrr!).

3. I retimed it to 10 initial. Sounds better; runs better; revs more willingly. Now it runs 185-190 when moving and goes up to 205 at long idle in 85+ degree weather.

So, I don't know if I'm done here ... probably will tinker some more, but it goes to show you how timing will affect temp.

BTW - anyone ... feel free to comment on my comment ;o)

~Bill
 
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