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#1 |
Registered User
![]() Join Date: Aug 2008
Location: Central TX
Posts: 393
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Engine runs hot
I have read several posts and picked up many tips and ideas. I have thoroughly been through the cooling system but engine still runs hot. I have a 292 6cyl with around 15,000 miles on rebuild. Manual transmission.
new water pump 3 row radiator - just rodded out have tried 195, 180 & 160 thermostats - back to 180 new temp sending unit hooked up alternate gauge - reads same as factory ditched 4 blade stock fan - installed 6 blade checked dash gauges ground wire new 13 lb radiator cap recent tune up - timing at 4 btdc The engine does not act like it is running hot. No knock, rough idle or coolant boil over. The fan blade change out was the last thing I did and it seemed to help a bit. Factory gauge runs a little over 2/3 instead of 3/4+ (see pics of gauges taken before fan replacement). The only cooling system issue I can think of at this point would be the new sending unit is faulty. The sending unit I replaced gave same reading though so what is the chance of 2 faulty sending units. There is a slight amount of valve chatter, could valve lash cause engine to run hot? I have not tried drilling holes in thermostat, maybe an air pocket? Maybe the engine is not running hot but looking at that gauge running past the 1/2 way mark drives me nuts!!! http://i420.photobucket.com/albums/p...16/Misc002.jpg http://i420.photobucket.com/albums/p...16/Misc003.jpg |
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#2 |
Registered User
![]() Join Date: Jul 2007
Location: Toppenish, WA
Posts: 15,519
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Re: Engine runs hot
Ok why do you say it is running hot? is it the reading on the gage or is it boiling over? A little explanation might help here.
If I didn't trust the stock electric gage I'd buy a good mechanical temp gage and mount it under the dash and see exactly what the real temperature was. |
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#3 |
Senior Member
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
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Re: Engine runs hot
i agree on double checkin gauge readings// i have a known good thermometer that i just dip into the radiator//you can get pretty acurate thermometers at the supermarket or cooking supply store//to check a thermometer for accuracy just dip in boiling water
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71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY Last edited by cdowns; 10-28-2008 at 02:55 AM. |
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#4 |
Registered User
Join Date: Sep 2008
Location: Portland, Oregon
Posts: 286
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Re: Engine runs hot
Test the thermastats. Get a good one form say Stant. Drill a few little holes in the flange of the thermastat to allow water to flow by the wax filled cup on the thermastat. If you still have a problem remove the thermastat. If that does not work, either your radiator is clogged or the pump is bad. Sorry but its never an easy solution trying to locate a problem like that. Good Luck.
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#5 | |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
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#6 |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
Also, I went to back the raditor shop after putting radiator in. He performed test that detects exhaust gases in coolant. None detected. That should rule out head gasket leak. He recommended better fan since there is no shroud.
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#7 |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
Have good meat thermometer, will give this a try. it runs hot even without radiator cap on.
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#8 | |
Registered User
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Location: Central TX
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Re: Engine runs hot
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#9 |
Registered User
Join Date: Sep 2005
Location: Smith Mountain Lake Virginia
Posts: 1,537
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Re: Engine runs hot
You shouldn't put sealant on the temp sender either.
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"A cat will almost always blink when hit between the eyes with a ball peen hammer" (you don't always have to state the obvious) Wear your PPE! You can eat with false teeth but you can't see with a false eye. 1959 Studebaker Silverhawk 350/400 1972 C10 L6 3OTT 2005 F350 - Built - whew! |
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#10 |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
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#11 |
It's a catastrophic success.
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Location: Oklahoma
Posts: 2,077
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Re: Engine runs hot
Do you have the fan spacer that puts the fan closer to the radiator?
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#12 |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
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#13 | |
Sierra Grande Club
Join Date: Jan 2007
Location: New Mexico USA
Posts: 2,433
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Re: Engine runs hot
Quote:
Is your block grounded to the frame & firewall? s/t
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#14 |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
Will check ground to frame and firewall too. Only ground to firewall is stock braided copper strap from head to firewall. Need to check block to frame though. I have voltmeter, how do I check sending unit ground?
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#15 |
I wish I was a cowboy
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Location: Rohnert Park, CA
Posts: 409
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Re: Engine runs hot
With all the things you did, you knocked out about 95% of what normally causes running hot. Have you tried a coolant flush? You can buy a $10 kit from the parts store that adds a threaded hose connector to your heater hose, so you can run garden hose water through it - running or not. I did so on mine a few months back as I was getting no heat from the heater even though thermostat/water pump/heater hoses were good. Got tons of gooey junk out. Heater is hotter now, but still not toasty, so I have have a heater core that's corroded to the point of blocking coolant flow (although that's not your issue, most likely). Maybe there's blockage in the coolant passages...could be gasket sealer, rust, or other junk. No coolant flow = hot block, cool radiator.
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#16 | |
Registered User
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Location: Central TX
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Re: Engine runs hot
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#17 |
Registered User
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Location: Charlottesville, VA
Posts: 404
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Re: Engine runs hot
Not to steal the thread . . . But where do you get a fan spacer? My 350 is mounted in the inline 6 location so my fan sits just about 1 1/2 or 2 inches away from the shroud.
Back to the thread . . . Mine ran hot - 240 at idle - but had a small in line 6 radiator and no shroud. Put in a 4 core and a shroud and it runs at 180 - 190 now.
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#18 | |
Registered User
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Location: Central TX
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Re: Engine runs hot
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#19 | |
Prostreet 72
Join Date: Oct 2008
Location: Goodrich, Michigan
Posts: 278
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Re: Engine runs hot
Quote:
Just a question, do you use a fan shroud? Last edited by Prostreet 72; 10-28-2008 at 12:45 PM. |
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#20 |
Registered User
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Location: Central TX
Posts: 393
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Re: Engine runs hot
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#21 |
Registered User
![]() Join Date: Aug 2008
Location: Central TX
Posts: 393
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Re: Engine runs hot
Will not have time to get my head under the hood until this weekend. Here is what I plan to check.
reinstall temp sender unit with no thread sealant check water temp in radiator with cap off- although I am concerned with coolant temp at cylinder head. look into installing mechanical temp gauge to see what temp is at head. if none of these solve it I will be looking for 4 row radiator and mounting brackets Thanks everyone for all your input - I will keep you posted |
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#22 |
I am a Referee of life.
Join Date: Jun 2000
Location: Greensboro N.C.
Posts: 13,993
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Re: Engine runs hot
One of the Arizona members has a 6 and 4 core radiator.He has used a fan shroud and clutch fan.Hopefully he will post his set up again so I can copy it too.
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#23 |
I wish I was a cowboy
![]() Join Date: Apr 2008
Location: Rohnert Park, CA
Posts: 409
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Re: Engine runs hot
Put 12v on the red prong of the voltmeter, touch the black prong to the body of the temp sending unit (not the connector!). You should show very little resistance. By moving the black prong of the meter to the connector, the resistance should shoot up if cold. If it only jumps a little while cold, your temp sensor isn't doing it's job: When cold the resistance of the sending unit should be high, when hot, resistance declines (no resistance, meaning a short, will shoot your guage up to 240+).
Guys, chime in here...that 6 cyl and stock radiator/"shroud" should keep this thing at about 180 idling in normal outside temperatures, right? You shouldn't have to install a 4-core, shroud, and all that. There's something wrong with the reading, air flow, coolant flow, or ignition timing/carb mixture. You're on the right track, though.
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-Kris Met list: Cyclone,Wilson,TranzAm,extd56,hotrodhomi,mnky30,Rokcrln,Brad,JerryJones(well, his truck anyway). |
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#24 |
Rusty Nuts
Join Date: Sep 2008
Location: Clever Missouri
Posts: 1,338
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Re: Engine runs hot
I would check your timing, i have had first hand experence with this on a 235 six cylinder and after all the thing you have done i did. and went to the distributor and sure enough adjusted the timing and problem gone.
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#25 | |
Registered User
Join Date: Sep 2008
Location: Ogden Utah
Posts: 286
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Re: Engine runs hot
Quote:
Timing too retarded can cause to run hot too. I would get the timing dialed in.. and not pay too much attention to the guages.. if it's hot.. you will know it. Do you seem to lose a little power too when this is happening. |
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