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4.7 stroker running hot???
Posted: October 12th, 2010, 10:52 am
by bill_durango
I have a Titan 4.7 stroker that seems to be running hot on me. It runs cool(er) at idle or when crawling around, but seems to be running hotter when pulling hills or on the freeway?
I installed a HESCO high flow water pump when the engine went in, I have a wide band O2 sensor that shows the engine maintaining around 14.7 while driving, new fuel pump, 24 lb injectors, 47 lbs set at the fuel rail and new MAP sensor... I replace the radiator with a larger 3 core brass unit, installed a Taurus high speed fan and even moved the temp sensor to the thermostat location at the front of the block, thinking it was not getting good water flow at the back of the engine (I also dropped the t-stat to a 180 degree unit). new coolant with "water wetter" added.
On long pulls it get up to 230-235 degrees, not overheating or boiling over, but it seems like it should stay no higher than 220?
What temperatures are your strokers running?
Any ideas on what could be going on???

Re: 4.7 stroker running hot???
Posted: October 12th, 2010, 12:05 pm
by Cheromaniac
Mine runs at 180*F on the highway in 100*F weather with the AC off, and at 190*F with the AC on (stock 2-core radiator, 180* t'stat, Flowkooler water pump). Yours should be running a lot cooler than it is and I think the culprit is the radiator. Yes, I know it's a 3-core but often the pipes in these cores are smaller and don't flow enough coolant.
I recommend a new OEM 2-core radator but before you swap radiators, try pressure washing the AC condenser with a hose 'cause if that has thick dirt between the fins, it won't allow enough air to reach the radiator. It might help and it's worth a try.
Re: 4.7 stroker running hot???
Posted: October 12th, 2010, 12:33 pm
by bill_durango
It's a brand new radiator installed two weeks ago and the AC condenser is also brand new
Any other ideas??
Re: 4.7 stroker running hot???
Posted: October 12th, 2010, 1:24 pm
by lafrad
I've seen quite a few posts that the "3 core" radiators are not nearly as effective as the 2 core, or even "aluminum" OEM radiators. I have one of the 1"- thick 1core radiators with plastic endcaps (yuck I know, but it was cheap) and it hasn't had a single problem keeping cool... even 100* days going slow off road had no issues last summer.
Re: 4.7 stroker running hot???
Posted: October 12th, 2010, 2:02 pm
by bill_durango
I replaced the all aluminum radiator, that was also new with the new brass larger 3 pass and it still has the same issue...
Any ideas other than radiator??
Re: 4.7 stroker running hot???
Posted: January 18th, 2011, 7:34 pm
by gdlocal10
That is crazy, I am just looking into 1 of those 3 core radiators, sounds like you have tried everything, I wonder if your timed too fast, or too rich on the fuel, or is the exhaust breathing proper,I'm not sure how touchy these new engines are, How many miles on the Titan?I'm building one of those engines, getting some of the parts from Titan, boy are they slow. I was wondering if a high flow water pump moves the water too fast, and the radiator cant cool it as fast as it is moving. Just a thought. Courious to know how it goes
Re: 4.7 stroker running hot???
Posted: January 18th, 2011, 8:54 pm
by gdlocal10
I had another thought, check the heater valve, if your line that goes from the thermo housing to the heater core has a valve in it you might need to replace it. I had a olds that overheated like that and found out that that vaccum valve was bad and stopped the system from proper circulation. Just a thought.I was advised by an older mechanic to check that. And in that case he was right .good luck
Re: 4.7 stroker running hot???
Posted: January 19th, 2011, 11:12 am
by Cheromaniac
lafrad wrote:I've seen quite a few posts that the "3 core" radiators are not nearly as effective as the 2 core
I've had first hand experience of that in my Jeep, which is why I won't run anything but a factory 2-row radiator from now on.
Re: 4.7 stroker running hot???
Posted: January 21st, 2011, 2:08 pm
by aaronkeiser
I had the same issue your talking about...I loosened the Temp sensor on the front of the thermostat housing and bled the air out that way. Like you I put a 180 thermo in to see what would happen and it did nothing. At idle it would go up to 230ish and on the freeway it would go up past 220 but cruizing around town at 25-45ish is would run fine(roughly 200). Only after I put a 195 thermostat back in and bled it did it work right.
Re: 4.7 stroker running hot???
Posted: January 22nd, 2011, 6:45 pm
by Comanche91
X 1300 on the 3-core rad. I switched to a single core all aluminum rad and the running hot went away. Two suggestions:
1. Invest in an external infra-red thermometer and verify the accuracy of the dash temp gauge. They are notoriously inaccurate.
2. If your temperature climbs while going up long grades, a likely suspect is a clogged cat. I pulled mine and there was a black tar looking crap inside, and I could barely blow through it. Fitted a "test pipe" years ago, and no more high temps going up grades. I'm still testing the "test pipe".

Re: 4.7 stroker running hot???
Posted: February 25th, 2011, 1:33 pm
by herbiehind
isn't 14.7 waaaay too lean shouldnt you be around 11-1 . afr .or even 12 but not 14 .
Re: 4.7 stroker running hot???
Posted: February 25th, 2011, 3:52 pm
by SilverXJ
14.7 is right where it should be for closed loop operation. Which is when you are cruising. light acceleration, etc. Open loop is when you will see lower AFR number (richer),when you go in to WOT.
Re: 4.7 stroker running hot???
Posted: February 28th, 2011, 8:59 pm
by BDD
Im new to the jeep stuff but is your hesco pump spinning the rite direction? Dont v belts and serps turn diff directions?