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Changing the thermostat questions

rustystud

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Hey it wouldn't be the first time I said something and forgot.
I have to write myself notes to remember to do something the next day ! I have a special place on the kitchen counter. Funny thing is though, I can remember doing things in my forty's and earlier like it was yesterday ! It's these last 2 decades that are becoming blurry, except work though. Funny that of all my memories that remain it has to be of work !!!
 
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74M35A2

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I know this is an old thread, but Welldigger said to replace the seal because if you don't, it will run cold around town and hot down the highway. I'm not sure what condition the seal has to be in, but mine was intact when I (actually 74M35A2 changed it for me) changed it. I put in the Napa thermostat referenced in this thread. My issue is that the truck runs very cool. It is advertised as a 180 degree thermostat and when it is 50 degrees out, it will only run about 160 degrees. The cooling system is full, I am sure of that. I just don't know what it could be that makes it run so cool. I put the winter front cover on it and that helps out a lot. I just wish the engine temp could get to 180 degrees easier and stay there in not so cold temps. Any suggestions?

Also I think there is confusion in this thread saying the seal number is 4662 and in another spot is says it is 4622 (in post #17). I checked the same post that says the seal number is 4622 and his picture shows the seal as part number 4662. He just made a typing error. Maybe one of the moderators could correct this if possible? Thank you if you can.
Take the metal direct drive fan off, and send it to China to be recycled into a Wal-Mart bicycle (or in your case trade it at the Findley swap for 25 new 9.00 - 20 NDT tires). Put a 24V electric fan on with a 195F on/off switch and relay, and be done with it. Sit back and enjoy much more consistent engine temps, faster warm ups, increased HP delivered to the wheels, increased fuel economy, reduced belt issues, and much reduced under hood noise. Multiple benefits here! I have done this on several applications, and have never looked back. You love the high tech gear reduction starter we put on, so keep going, bring this thing into some current technology! Your M35 would sound pretty bad a$$ sitting outside the boat club at an idle, with an electric fan suddenly turning on and off as needed.
 

frank8003

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Take the metal direct drive fan off, . Put a 24V electric fan on with a 195F on/off switch and relay, and be done with it.

Just like my 9C1, when the relay dies then the secondary the thing is toast

Stick with the original design, the thing was built as a tactical military
contraption to get what was needed to wherever it needed to go,
no matter how heavy. I like an engine driven fan.
And I will trade my water pump + fan at any time for 25 new 9x20 NDT tires.
O.K. I went overboard, throw me a jacket.
 

rustystud

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I like electric fans and hydraulic fans, but I hate it when they go wonky ! The times I have spent troubleshooting electric fans and hydraulic fans are way too many ! Of course these are on transit busses and are computer controlled with all the relays and valves that go with it. I just like the simplicity of a direct drive fan on my personal truck. No relays or wiring or sensors to go out.
 

Wildchild467

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I like electric fans and hydraulic fans, but I hate it when they go wonky ! The times I have spent troubleshooting electric fans and hydraulic fans are way too many ! Of course these are on transit busses and are computer controlled with all the relays and valves that go with it. I just like the simplicity of a direct drive fan on my personal truck. No relays or wiring or sensors to go out.
Thats what I try telling 74M35A2. I like how the stock deuce fan is field proven and it works great. Its only a matter of time before an electric fan goes bad when you need it most. I run WMO for fuel and not really concerned about fuel mileage. Also don't care about speed that much.... if I did, I would re-power my truck with something that would give me 250 horse and be done with it. I love my Multifuel and wouldn't make any major modifications. I like things to be mechanical. My fan looked near new when I put it in after I rebuilt my truck 3 years ago.... so it should last a long time at my max engine speed of 2300. :)
 

Wildchild467

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I almost put one on mine last year, but after I thought about it for awhile I decided since I don't drive that many miles anyway "What is the difference ? " .
I put about 4000-5000 miles on mine a year. I drive it to work a lot and other things you need a deuce for... like getting groceries and going to ice cream stands ;-)
 

74M35A2

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Thats what I try telling 74M35A2. I like how the stock deuce fan is field proven and it works great. Its only a matter of time before an electric fan goes bad when you need it most. I run WMO for fuel and not really concerned about fuel mileage. Also don't care about speed that much.... if I did, I would re-power my truck with something that would give me 250 horse and be done with it. I love my Multifuel and wouldn't make any major modifications. I like things to be mechanical. My fan looked near new when I put it in after I rebuilt my truck 3 years ago.... so it should last a long time at my max engine speed of 2300. :)
"If you like your fan, you can keep your fan.". Ha! You can keep your fan Tommy Gun. Technology will pass you by with advances, and so will somebody with an electric fan! I respect your desire if to keep the truck original, but if it is function you are chasing, then a switched fan is the only way. I can't think of a single road application that uses a direct drive fan anymore. Even a full semi-tractor-trailer truck with a 15L ISX or DD16 rated to pull way over 40,000lbs load uses at least an on-demand air actuated clutched fan, which is setup as fail-safe to be direct drive (requires air pressure to free-spin, 0psi=direct drive lockup).

Your belts are squealing and you are wondering why your thermostat can't hold rated temp, but after we changed mine last night, it held rated temp just fine, including a freeway drive at 65mph, with no winter front cover. I'd go dollars to donuts that a large part of that is your direct drive fan vs my clutched fan. I could engage mine solid, or you take yours off, and do 2 back-to-back tests, and let the data talk.

Rusty has a point on complex systems, especially low volume electronics like buses, but of simplistic or high volume mass produced systems, I have yet to see a failed one in the past several decades. When people say "They just don't make em' like they used to.", I am immediately following them with "Thank goodness", as when was the last time your car stalled backing out of the driveway? You probably don't remember the days of stuffing a pencil down a carb to keep the choke open after it flooded out during a start attempt.

If I call you that I'm overheated on the side of the road, I'll gladly print and eat this page. Though it is not what I would do, I respect your choice and would help you support it if need be, and you know that. How is that modern square wire alternator working on your Jeep I picked out? Kind of boring putting out 160A, and 90A at idle alone huh? Maybe that is too advanced and we should take it off and put an old Motorola 25 amp DC generator with external point style regulator box on your Jeep? I think some of those have a tach drive cable, so you should probably switch over to that also and you can watch it bounce around.

As somebody that designs and builds systems, I stand firm on this one. Keep your direct drive fans, and we'll drink beer together, but the only time you'd see me with a direct drive fan is if somebody throws one in my casket just before they close it.

Thanks for all the help last night, I could not have done 2/3 of what we got done without ya' bro.
 

Wildchild467

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"If you like your fan, you can keep your fan.". Ha! You can keep your fan Tommy Gun. Technology will pass you by with advances, and so will somebody with an electric fan! I respect your desire if to keep the truck original, but if it is function you are chasing, then a switched fan is the only way. I can't think of a single road application that uses a direct drive fan anymore. Even a full semi-tractor-trailer truck with a 15L ISX or DD16 rated to pull way over 40,000lbs load uses at least an on-demand air actuated clutched fan, which is setup as fail-safe to be direct drive (requires air pressure to free-spin, 0psi=direct drive lockup).

Your belts are squealing and you are wondering why your thermostat can't hold rated temp, but after we changed mine last night, it held rated temp just fine, including a freeway drive at 65mph, with no winter front cover. I'd go dollars to donuts that a large part of that is your direct drive fan vs my clutched fan. I could engage mine solid, or you take yours off, and do 2 back-to-back tests, and let the data talk.

Rusty has a point on complex systems, especially low volume electronics like buses, but of simplistic or high volume mass produced systems, I have yet to see a failed one in the past several decades. When people say "They just don't make em' like they used to.", I am immediately following them with "Thank goodness", as when was the last time your car stalled backing out of the driveway? You probably don't remember the days of stuffing a pencil down a carb to keep the choke open after it flooded out during a start attempt.

If I call you that I'm overheated on the side of the road, I'll gladly print and eat this page. Though it is not what I would do, I respect your choice and would help you support it if need be, and you know that. How is that modern square wire alternator working on your Jeep I picked out? Kind of boring putting out 160A, and 90A at idle alone huh? Maybe that is too advanced and we should take it off and put an old Motorola 25 amp DC generator with external point style regulator box on your Jeep? I think some of those have a tach drive cable, so you should probably switch over to that also and you can watch it bounce around.

As somebody that designs and builds systems, I stand firm on this one. Keep your direct drive fans, and we'll drink beer together, but the only time you'd see me with a direct drive fan is if somebody throws one in my casket just before they close it.

Thanks for all the help last night, I could not have done 2/3 of what we got done without ya' bro.
I was ever going to put an electric on it, I would want it to be top quality with a field proven track record. I would want to update my alternator to a field proven modern one too (just because mine looks like it is old and not like an NOS one (higher mileage i think). one thing i don't like is when modifications are done and you can tell there was no attention to detail and it looks like a cob job put together. Another thing to add, I would never hack up my original radiator for provisions for an electric fan. Some newer technology is good... square wire alternators are nice. If I could put one of those in the place of my 10SI I have for my 12 volt system, I would if I didn't have to change my already made bracket.

My belts used to squeek because i had the wrong style alternator adjusting arm which was preventing me from getting a little more belt tension. I now have the right one and have not had any more problems since. Works like a charm.

Mechanical tachs are fine... just lube the cable and be done. Technology is ok, but that does not mean I would want it for everything. When i saw they made an experimental Hybrid FMTV, i was skeptical. I wouldnt want that thing at all. So what about the slight gain in acceleration and possible slight fuel mileage increase. I was not happy with the mechanical design. So what if you could export power from the engine mounted traction generator. If you have floods like we did in NY a few years back... you mean to tell me that that electrical system will function flawlessly? What about being in battle... one piece of shrapnel takes out a computer chip and then you are dead in the water... truck wont move. no thanks. Ill stick to non computerized transmissions all day long. Mechanical things just plain work when taken care of. :)
 

Jeepsinker

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And having vehicles with a control module in every seat and door, body control module, multiple drivetrain control modules, all of which can and will just decide to up and take a giant $hit on you for no reason is so much better than having a carburetor flood once in a while. Seriously though, door and seat control modules? What, because switches and relay weren't good enough? Yes, new technology is great to a certain extent, but it gets to a point where it is almost dragging you backward in the reliability side, and it certainly isn't as user serviceable.
 

rustystud

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And having vehicles with a control module in every seat and door, body control module, multiple drivetrain control modules, all of which can and will just decide to up and take a giant $hit on you for no reason is so much better than having a carburetor flood once in a while. Seriously though, door and seat control modules? What, because switches and relay weren't good enough? Yes, new technology is great to a certain extent, but it gets to a point where it is almost dragging you backward in the reliability side, and it certainly isn't as user serviceable.
Can you believe our new buses have a computer controlled muffler system !!! There is more electronic crap on these things then "you can shake a stick at" ! There are 5 main modules just for the interior electronics. Then there are the engine ECM the transmission ECM and the traction control and anti-lock brake ECM. All talking to each other ! Along with the muffler ECM !!!
These buses have the "Hybrid" transmissions in them and I say " what a waste!!! " . The fuel economy is worse then the older "Standard" buses. Yet these things cost almost 1 million dollars each !!! $987,000 !!!! I should not be so hard on them, after all they have sent many kids to college from all the overtime work ! It has reached a point where it is just put in new technology for new technologies sake. Forget about making it better.
 

Adam Brice

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Look guys, a newbie found a thread that had already been posted and added to it instead of making a new one.......:-D

Anyways, what did you ever find out about this o-ring? I pulled my stat tonight and cooked it and It looks like its opening fine to me (190 or so) and it looks like its open as far as yours. Thing is, after pulling the stat out of the housing, I looked at my o-ring and the metal part is fine but the rubber on the back side is coming off. Does this matter/ should I just pull the rubber off, toss it and keep on moving? Also, do I have to replace the gasket on the housing or can I just scrape the old one off and seal it up with RTV? Thanks!!!
Lol! Now I'm the newbie, and looking up old posts!
 
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