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| thermostat; 160, or 180 | |
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| Tweet Topic Started: Sep 19 2012, 09:48 PM (1,211 Views) | |
| Bob_webber | Sep 19 2012, 09:48 PM Post #1 |
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i am preparing to get a thermostat for the f head, and i am wondering which one is best for the motor.(either is better than none i am guessing) since i am installing a heater i am guessing the 180 degree will be better for my comfort, and defrosting capabilities. but i am not sure about summer time, the engine will be running hotter making the interior hotter especially on rainy trips. the 160 will open sooner and produce heat faster but will not be as hot in the winter, but will be more comfortable in the warm season. has anyone run both and or have a preference? is there anything that will help or hinder the little f head with this decision? any idea what they came with originally? |
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53 3b, early cj5 frame (hurricane),2.43 ratio t case 26 tooth with 1 1/4" case (my own creation), late 60's c5 ross steering box, all range od, parts from a welder generator, and parts from about 9 different jeeps and counting. my every last penny and ounce of patients creates what we call the FrAnken B, the jeep that never was bob, north east Ohio | |
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| Rus Curtis | Sep 20 2012, 10:09 AM Post #2 |
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Bob, First a quick clarification on heat regardless of thermostat. The water that circulates through the heater completely bypasses the radiator and thermostat. The cutoff valve is on the top right (in the rear) of your head. The other hose is connected directly to the pump. Therefore when the heater valve is open and the engine is running, coolant is circulating and the heater will produce heat as soon as the engine begins to warm up - well before the thermostat opens. My technique on any engine that has a temp gauge, concerning heat, is to delay turning on the heater until the needle begins to rise. Then I know 'some' heat is being produced by the heater. As it warms, more heat will be produced by the heater. Once the thermostat opens, the temperature is then regulated by the larger radiator in front of the engine. As you know, the heater is also a radiator - just a bit smaller. The best way to stop heat from emitting out of the heater during summer is to turn the shut-off valve to close. This stops the flow of hot water through that small radiator inside the jeep. Second, the temp rating of the thermostat is intended to keep the engine running efficiently. A cold engine can't run efficiently and damage can occur if the engine runs too hot. My SM's state the following ranges: Early F-Head range - begins to open at 165 and is fully open at 188. Note: The L-Head engine range has a lower temp range (150-170). Later F-Heads show a higher temp range (180-202). This higher value actually had a stated thermostat rated temp associated with this range: 190 degrees. Using this, you could deduce the rating for the earlier thermostat to be either 170 or 180. I don’t know why the temperature increase occurred between the early and late F-Heads. You are correct that having any thermostat is better than none. The engine temperature affects the atomization efficiency of the intake manifold as well as the combustion. It also works in unison with the lubrication and its cooling effects. What you end up choosing would probably depend on where you live, i.e. the temperature range throughout the year, and how your jeep runs. You may find one or the other works better to make your engine happy. But if it were me, I’d start with one that works with the stated range and go from there. |
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Rus Curtis Alabama '54 CJ-3B "Green Gruntt" Bantam T3-C | |
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| Bob_webber | Sep 20 2012, 04:56 PM Post #3 |
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rus, i never thought of it that way that is pretty cool. i also never thought of being able to shut that valve off in the summer (i'll have to free it up though) i believe i have an early production f head, so i am going with the lower range thermostat. as always, many thanks
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53 3b, early cj5 frame (hurricane),2.43 ratio t case 26 tooth with 1 1/4" case (my own creation), late 60's c5 ross steering box, all range od, parts from a welder generator, and parts from about 9 different jeeps and counting. my every last penny and ounce of patients creates what we call the FrAnken B, the jeep that never was bob, north east Ohio | |
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| Doug | Sep 20 2012, 05:47 PM Post #4 |
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Meridian, Idaho
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I have been running the 160* thermostat in my 63 since I got it on the road (4-5 years). I have the large instrument cluster and my temperature never rises even to the half way mark. I always assume that the half way mark is a good place for it, so my engine appears to run cool. I will be installing a 180* thermostat in my rebuilt engine due to engine efficiency that Rus was talking about. |
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1963 CJ3B - F134 Hurricane, T-90C, D-18, 5.38s, Overdrive, 938YF, 12V alternator 1969 CJ5 - Dauntless V6, T-14, D-18 2004 TW 200 | |
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| oldtime | Sep 20 2012, 06:38 PM Post #5 |
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Yes Rus put up a good reply. And it's correct on all points. Fact is that you don't want the engine to run too cool. Running too cool probly causes more excess wear than overheating ever does. A good machinist will always measure the #1 cylinder when reboreing a block to determine the rebore size. The #1 cylinder wear is normally greater than the other cylinders because it sets closer to the water pump. I have an original 1953 bellows type thermostat. It opens at 166* On my daily driver I run a 180 * thermostat and my temperature needle sets just above the midway point on a blistering hot day. Its a 1980's replacement radiator and I never even installed the shroud because I did'n t want to modify slightly it to fit the radiator. I will estimate the ideal running temperature is about 185*- 210*. |
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Currently building my final F-134 powered 3B . Rock Crawler using factory parts from the Willys Motors era (1953-1963) http://s4.zetaboards.com/CJ3B_Bulletin_Board/topic/30228766/1/#new | |
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| bob east texas | Sep 26 2012, 07:23 AM Post #6 |
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I ran my Jeep many years before I learned it had no thermostat. I always had plug fouling problems. After adding a thermostat all engine functions improved. If you wonder whether you have one, start the engine cold and open the cap to see if coolant is circulating fast. If so, then no thermostat is installed. No circulation tells you that there is one. |
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| Bob_webber | Sep 26 2012, 11:43 AM Post #7 |
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update, i decided to go with the 180 deg thermostat, so i went to autozone and got the cheapest one i could find(we can all see where this is heading). i bought the valucraft brand, big mistake to make a long story short i had to tap the goose neck with a crescent wrench to get it to open. i watched the temp and it did not get over 220 while running, and i filled the block from the thermostat housing before i installed the thermostat. even after i managed to get it to work it opened and shut very erratic and sometimes i had to bump it again to make it work. the next day i went and got a different brand at a 160 deg installed it and realized that i blew the seal on the front of the water pump the day after that i put a used water pump off another f134 on, and while doing that i managed to bump my already shaky radiator. so now after work i will have to pull my radiator and have my father solder it (one skill i can never seem to master). all for the love of a jeep <_< |
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53 3b, early cj5 frame (hurricane),2.43 ratio t case 26 tooth with 1 1/4" case (my own creation), late 60's c5 ross steering box, all range od, parts from a welder generator, and parts from about 9 different jeeps and counting. my every last penny and ounce of patients creates what we call the FrAnken B, the jeep that never was bob, north east Ohio | |
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