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Need advice

My motor is a 2.0 stock with an I.E. Aluminum radiator and electric fan from I.E. 

180 degree thermostat.

The engine is running hot even on the freeway on cool 65 free days.

15 min at a stop at In n Out burger and the radiator is steaming, the temp gauge is fully in the red.

 

What do you guys recommend?

 

Thanks

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Test the thermostat in a pot of near boiling water to confirm it is opening.

I would dump all coolant and drain the block.  The plug is under #3 (#4?) exhaust port.  If sludge comes out or it's plugged, that could be a problem.

 

Edited by PaulTWinterton

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In addition to PTW's astute recommendation, check the entire system - from the radiator cap (that might not be holding adequate pressure) to the radiator itself for coolant flow as well as external air flow.  The fact that the radiator is aluminum or an aftermarket product or even new - does not prevent it from becoming gummed up with scale and debris - internally or externally.  Even before draining the coolant, it would be comforting to see a decent coolant flow near the top of the radiator - indicative of a water pump that is doing its job.  (There have been occasions where the impeller has corroded away, or in the case of a plastic resin impeller, losing some of its vanes.

 

Another thought is that overheating is not necessarily a product of a compromised cooling system.  It may sound condescending but retarded ignition timing can contribute to an engine running hot. 

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Was the engine running at normal temps prior to the new radiator and fan?  If you backtrack, is there something that changed that could be the culprit?

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Thank you all, great advice.

I have a lot of things I am going to check.  Ordered a 153 degree thermostat today.

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You DONT want a low temperature thermostat. All you are doing is changing the symptom, not curing the problem.

 

Follow the advice that has been given to diagnose the problem. Test the existing thermostat. Check for sludge. Check the flow.

 

To reiterate dang's question, what was happening before the expensive new parts were fitted?

 

Sorry if I sound a bit snappy ;).  

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When it is running hot, try setting the heater on Hot and the heater fan on full.  If the temp gauge needle comes down significantly, it could indicate a plugged radiator, where the added cooling capacity of the heater core brings the temp back down.  If nothing much changes, it is probably the thermostat, assuming the timing is correct.

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Borgpj has a good point you could also have an air pocket in the system that needs to be bled out . Old trick , jack up & support the front of the car as high as possible, make sure heater valve is open , fill radiator , I squeeze the top & bottom hoses too , then run it make sure the hoses to & from the cabin are hot indicating the heater valve is open. Check the 3 hoses on the thermostat they should all be hot also . See what happens once you know the system is bled . Also I run an overflow catch can so my system is always full , 6 2002's & no overheating , even my track car daily driver runs cool & I only run the fan when in stop & go traffic,

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+100 with LimeySteve's suggestion.

 

I have struggled with my '75 for some time.  As long as it had air going thru the radiator, temps would hang at 3:00.  Slow in traffic and it would almost immediately bump to 2:00, and climb... This was after a new 320i rad, fully flushed system, and 40/60 mixture.  What the heck???  

 

I had elevated the front of the car and squeezed the hoses as always recommended... I had just about succumbed  to the fact it was always gonna run warm.... till last week.  I was going on a trip of several hundred miles and I performed the ritual check of fluids and such.  The water level in the rad was down to the fins... Hello??  I topped it off with coolant and off I went.

 

Since then, the temp gauge has never wavered from 3:00; even stopped in traffic with humid, 98 degree ambient temps and the air conditioning running full blast. I'm now convinced there was an air pocket causing poor circulation in the system. My coolant level is now steady.  Also, like Steve says, my hotrod '71 never flutters... always steady temps.  I'd flushed that system in the past and never had troubles.  All cars are different...

 

I know on later BMWs there is a small bleed-off screw near the radiator.  You start filling the system and unscrew the bleeder and it hisses as air is vented from the cooling system. Once nothing but water comes out the vent, you tighten it down and off you go. Our cars need something like this, me thinks...

 

I suppose one could run with the rad cap loose for a while and any air would eventually find its way to the top end of the radiator (which is what happened in my instance).  In any case, my car finally burped and she runs nice and cool now. ... this with the 80 degree thermostat in Texas heat.

 

As a side note, check your timing... too advanced will make it run hot, but you'd likely hear pinging in this case.

 

Good luck and be sure to report back with a solved problem!

 

Ed

 

 

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You don't mention, but are use still using the red engine fan and shroud ?  or just relying on the electric fan ? 

Without the engine fan, the car should run at a medium heat when you are moving above 30 miles per hour, but will heat up fast in stop and go traffic or even a long red light

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+1 zinz.  I leave the radiator cap loose and take a drive around the neighborhood to bring the temp up to normal, this has worked for me to get any air out of the system.

 

After a radiator re-core several years ago I began using a (approximate) 15% coolant/85% water mix.  50/50 was making it run "hotter" than I wanted ...... with more water the temp now runs 4:00 on the gauge.

    (weird:  on a cold morning the temp is 2:30 to 3:00 ..... as the day warms up, the coolant drops down to 4:00).

 

Cheers,

 

Carl

 

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Thanks everyone for great advice, I appreciate everyone taking the time to respond.

 

732002Malaga, thank you for the offer to come by to help.  

 

Problem solved, I'm so happy.  I adjusted the electric fan to turn on at lower temps,  used a bottle of Wetter Water, topped off the coolant and used a 71C thermostat.  Now the gauge is in the middle.  Next I am going to borrow my buddy's temp gun and check the true engine temp.

 

So glad not to stress over the motor getting too hot.

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