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Thermostatic Fan Clutch

The EVANS boils at just under 400 deg f. & totally eliminates steaming and the resulting cavitation because no water is used and it pulls more heat as a result however there needs to be a way to pull all that heat out of cooling system. I sealed all gaps between the radiator support and radiator even under the upper shroud assembly that cover the top of radiator so all air flows through the radiator as opposed to some going around the radiator at the gaps.
 
Schiker you are close. It is the water pump not the fan clutch why you want the spin on. The ho bolt on water pump and the spin on both 130gpm, compared to the 100 gpm original pump. The difference in the spin on vs ho is the flow through the 2 sides of the block/head is balanced in the spin on. With the original pump and ho pump the passanger side head takes all the abuse because it gets far less flow over it. Getting the spin on pump imo is the #

Couple that with the rear cylinder trapping more heat than the others next to the transmission and that is why cylinder #8 always bites it first and the worst.
 
Max 40%. I've tried everything from 20 to 50%. But I'm at around 40% now. I'm pretty sure unloading d up a hill i should stay at the 195 stat temp.
 
Have the restrictor and have taken both coolers off and pressured washed them clean multiple times. My fins look good on the condensor and radiator too. It was rodded and hot tanked at a shop. Haven't done the IR temp verification yet but at about 220 my cap blows and steam comes out

I would pressure test your cap. Don't just replace it as you want to know if it is popping off early and the cause of the issue. I had a bad cap shock cool my engine when it suddenly let off and it scuffed the #1 piston that later cracked and burned through. It sucked the hoses flat that evening when cooled down.

If you have a low temp KD fan clutch it should not need the spring mod. After using them IMO there is something else wrong.

I would look at other things like a restricted exhaust etc.

The thread on water pump is supposed to be the best as it balances the flow between banks. Older pumps flow more to the driver's side head and overheat the passenger side. In other words you can be boiling over and then temp gauge reads normal. This also affects 350 gas engines. IMO GM screwed the pooch when they went reverse rotation for the serp belt and it took them years to figure it out.

I have used new 4 bolt HO water pumps and they did well in the AZ extremes of towing I did. As KD now has a thread on clutch I would go that way on future builds.

You always want a NEW virgin water pump not a rebuilt pump as the rebuilt pump could have used a housing with the balance flow issue.

Reference:

http://www.maxxtorque.com/2009/09/heath-diesels-65l-diesel-heavy-duty.html
 
Will L., I use EVANS have measured the temps across the cylinders after a hard run (many times) and it's all the same with a few degrees of each other after hard runs so I am of the opinion because the EVANS eliminated the steaming and cavitation by eliminating the water the higher heat trapped at rear cylinder is eliminated.

The only real way to confirm this past what I have done is to install aircraft spected temp sensors at each glow plug connected to an appropriate cylinder temp gauge and watch in real time, cost about $1.3k for quad cyl temp gauges x 2 and 8 temp sensors then making a harness and install.
 
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Some of the ones we use at work:3-4 samples per second.

http://www.omega.com/pptst/SA1.html

http://www.omega.com/pptst/TL-E_LABELS.html.

Definitely not going to be anywhere near as accurate as the set you mention.

I am considering the Evans. Do you have the spin on fan clutch style water pump? At what temp with the Evans is considered "into the danger zone"- (yes now old dudes are singing songs from top gun).
 
Some of the ones we use at work:3-4 samples per second.

http://www.omega.com/pptst/SA1.html

http://www.omega.com/pptst/TL-E_LABELS.html.

Definitely not going to be anywhere near as accurate as the set you mention.

I am considering the Evans. Do you have the spin on fan clutch style water pump? At what temp with the Evans is considered "into the danger zone"- (yes now old dudes are singing songs from top gun).

Yep, my Burb came with all the improved cooling system parts & spin on fan (steel) FERM states the composite DuraMax fan is better he used both and like you he's a wealth of knowledge.

I know we add did this dance before as temps go everything I've read allows newer systems with on board cooling system controller for fan clutch to run higher operating temps safely which also equates to more efficiency too however we are dealing with old school fan thermal engaged clutches (HAYDEN med trk) and figuring on between 195 deg and 205 deg f thermostats for best results. Remember, all those hot spots/pockets in the cylinder heads and cooling ports are directly related to water steaming & cavitation and lets not forget the turbo hanging off the passenger side cylinder head brings temps temporarily up close to whatever the EGT is then quickly dropping off center mount and Banks mount reduces this radiant heat problem.
 
Some of the ones we use at work:3-4 samples per second.

http://www.omega.com/pptst/SA1.html

http://www.omega.com/pptst/TL-E_LABELS.html.

Definitely not going to be anywhere near as accurate as the set you mention.

I am considering the Evans. Do you have the spin on fan clutch style water pump? At what temp with the Evans is considered "into the danger zone"- (yes now old dudes are singing songs from top gun).

It would be 2 quad cyl temp gauges right & left banks and be more a distraction than anything. The elimination of water is the key to better cooling of these diesels IMHO. I know you have concerns about cooling system failures like hoses being punctured or pulled off in remote off road situations I'd build guards to protect the hoses if really exposed.

Remember if adding water in situation where you sprung a leak then the water can be boiled off later consider zero pressure cap= not system pressure except pump head pressure in block which quickly falls off after leaving block and EVANS eliminating all cooling system corrosion, steam and cavitation which are the big culprits in cooling system failure to control internal diesel temps.
 
At what temp with the Evans is considered "into the danger zone".

Per EVANS site: it stays liquid up to 375F and has a flash point of 248F.

Put another way, the motor will likely to fail from rising temperatures prior to the coolant.


Noticed a change in EVANS' guidance regarding pressurization. When I first converted to EVANS, there was guidance that a hole in the pressure cap was acceptable. Now the guidance is to do nothing to the pressure cap (implication is that the coolant will naturally attract some moisture).
 
Moisture will always appear in system because of condensation a sealed system is no exception refractometer will bear witness to moisture content. In the many years running a zero pressure cap supplied by EVANS I've had no problems.

Any moisture will boil off around the valve area of the IDI cyl head almost as soon as you get underway and vent through steam lines into coolant accumulator and out from there gas engines may be another story all together.

I have people try to tell me running my transmission cold lets water accumulate too however fluid temps at torque converter commonly 300 deg f boils off any moisture.
 
Per EVANS site: it stays liquid up to 375F and has a flash point of 248F.

Put another way, the motor will likely to fail from rising temperatures prior to the coolant.


Noticed a change in EVANS' guidance regarding pressurization. When I first converted to EVANS, there was guidance that a hole in the pressure cap was acceptable. Now the guidance is to do nothing to the pressure cap (implication is that the coolant will naturally attract some moisture).

That 375 deg f is with a zero psi cap, a pressure cap only raises the boil point (I have a chart and will post) of the EVANS with less stress on cooling system components because there is no water to boil and create excessive pressure.

Flash point of 248 deg f is a non issue provided there is no direct ignition source @ overflow vent. The air flow in the engine bay/bonnet is such that it would dilute any fumes out the inner fender vent and down under the vehicle anyway even at idle an overflow tube can be extended to under the vehicle too. As far as I can tell there have been no reported fires from collisions that rupture cooling system w/EVANS installed.

I gone around with more than a few people about the operating temps for a 6.5td GM says 225 deg f +- and the military says 250 deg f +- temp is max then the argument comes into play like GM knows best then the military just does not care and replaces the 6.5 like it's no big issue.

Anyway my train of thought is that the 6.5 can run hotter and safely w/o water in the mix eliminating steaming and cavitation the two big enemies of the 6.5 diesel that are known to cause cracking of heads and blocks then getting rid of the GM series IHI turbos and the excessive back pressure and extreme superheating of the air charge.

The later GMT400 6.5td cooling system has bypass in thermostat housing to water pump and to the heater hoses some people prefer to simply shut the the flow to the heater hoses when not needed others like to install a restrictor in thermostat housing to water pump bypass then there is the option of completely blocking the thermostat housing to water pump and using full flow thermostats which are just drilled w/3 3/8" holes in both stats that are slightly larger in flow capacity than the 1" diameter thermostat housing to water pump bypass. Keep in mind that if your running EVANS and you use a heater hose shut off valve when you begin to use the heater you create another bypass which = cooler running temps.

Oh, the EVANS part number for the 205 deg f stat is E3020.
 
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I gone around with more than a few people about the operating temps for a 6.5td GM says 225 deg f +- and the military says 250 deg f +- temp is max then the argument comes into play like GM knows best then the military just does not care and replaces the 6.5 like it's no big issue.

Even the Ford 7.3's have the ring tension go away when you get them too hot resulting in lots of blowby. Rings are the weak point aside of cracking with high temps. All the Military surplus engines I got had bad rings including a set the 2nd ring didn't have a chance to fully seat. (And never did with 30K of hard miles put on them after I got it.) So what's that tell you about the mil temp spec?
 
Even the Ford 7.3's have the ring tension go away when you get them too hot resulting in lots of blowby. Rings are the weak point aside of cracking with high temps. All the Military surplus engines I got had bad rings including a set the 2nd ring didn't have a chance to fully seat. (And never did with 30K of hard miles put on them after I got it.) So what's that tell you about the mil temp spec?

I suspect all the failures revolve around antiquated EGW mixtures resulting in steaming, cavitation = superheated hot spots and GM's poor choice of a small turbine turbo w/o CAC/IC.

The EVANS has shown to be a vast improvement over EGW in preventing steaming and cavitation and many big rigs run higher operating temps w/o ring issues so I suspect these diesels can too but at what temp is the BIG question.
 
Be interested to see how hot IDI's can run without ruining the temper in the rings.

Big rigs are not running old IDI diesels anymore. The Fords with the same 'don't get the rings hot IDI issue' eliminate GM's bad turbo. Even NA engines ruined rings when you got them hot. All factors add up of course.

So unless somethings changed with 21:1 compression IDI rings they are still the weak point for higher temps.

I have Run Duramax engines at ECT's that turn 6.5's into scrap metal. And without ring issues on Duramax engines...
 
About the fire from the waterless coolant:
Fire from a collision, idk. But a blown head gasket- OH YEAH! You guys remember the guy I worked for some years back that has the "Morman Missile"...Its a good thing he had the fire suppression system in his little toy.
http://landspeedevents.com/blog/mormon-missile/

Lynn was one of the hardest bosses I ever worked for, but I still like the guy, and his whole enormous family for that matter. Hated to see this happen to him.

There are other cases of it causing fires, What happens is a mist sprays out and gets ignited. One happened at the auto cross out here a couple months ago. Radiator sprung a tiny leak and sprayed it on the header after the engine was shut off. I was with my nephew (a drifter dude) and he saw smoke coming from the engine compartment. We saw it ignite, and a little fire extinguisher is all it took.

Remember the flash point is tested by the point at which the liquid puts off a vapor that can be ignited by an open flame. Diesel fuel can be as high as 205 f and still meet specs. When the liquid gets sprayed into a vaporous state you do no need an open flame. Misting will lower the flash point dramatically- think fuel injector or carburetor. Does that mean I'm against running it because of that? No, gasoline cars are safe, so is this. But to think there is never a danger- no.
 
Be interested to see how hot IDI's can run without ruining the temper in the rings.

Big rigs are not running old IDI diesels anymore. The Fords with the same 'don't get the rings hot IDI issue' eliminate GM's bad turbo. Even NA engines ruined rings when you got them hot. All factors add up of course.

So unless somethings changed with 21:1 compression IDI rings they are still the weak point for higher temps.

I have Run Duramax engines at ECT's that turn 6.5's into scrap metal. And without ring issues on Duramax engines...

WW, I get your point there is an problem using EGW in the IDI however IMHO getting hot is mostly due to super-heated areas from steam pockets attributed to water boil and like any new or different product there are + & - to everything, I suspect if I reach the point of scrap metal using EVANS then it will probably be a 12 or 24 valve mechanical IP cummins for the burb.
 
About the fire from the waterless coolant:
Fire from a collision, idk. But a blown head gasket- OH YEAH! You guys remember the guy I worked for some years back that has the "Morman Missile"...Its a good thing he had the fire suppression system in his little toy.
http://landspeedevents.com/blog/mormon-missile/

Lynn was one of the hardest bosses I ever worked for, but I still like the guy, and his whole enormous family for that matter. Hated to see this happen to him.

There are other cases of it causing fires, What happens is a mist sprays out and gets ignited. One happened at the auto cross out here a couple months ago. Radiator sprung a tiny leak and sprayed it on the header after the engine was shut off. I was with my nephew (a drifter dude) and he saw smoke coming from the engine compartment. We saw it ignite, and a little fire extinguisher is all it took.

Remember the flash point is tested by the point at which the liquid puts off a vapor that can be ignited by an open flame. Diesel fuel can be as high as 205 f and still meet specs. When the liquid gets sprayed into a vaporous state you do no need an open flame. Misting will lower the flash point dramatically- think fuel injector or carburetor. Does that mean I'm against running it because of that? No, gasoline cars are safe, so is this. But to think there is never a danger- no.

If you consider the flash points of all the different fluids used under the hood/bonnet and the danger posed by them under different situations mostly modified race vehicles are always most at risk of fire.

The missile article makes no mention to EVANS so I'll take your word for it as you did work for them, you know if there are any documented incidents of regular vehicles used on or off road catching fire due to EVANS use? I'm not worried or concerned one bit perhaps this is foolish but I didn't get to my ripe old age worrying about all the things that could kill, disable or hurt me and didn't.

A fire suppression system is a good idea anyway but a hand held unit works well.
 
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Yeah, I first heard of Evans from that race car, so I attributed it as for race application and set the product aside from my thought of street use not knowing what were the long term effects. It was from that event that Evans and others like it have been banned from SCTA events (all the land speed records and such). The fire suppression system was a safety requirement he had to have on the streamliner.

Like I was saying I think it's still safe to use people just need to be aware of it. The fire suppression system was a safety requirement he had to have on the streamliner.

Like I was saying I think it's still safe to use people just need to be aware of it. I just don't want to see anyone having a open Style reservoir overtop of or right next to exhaust or turbo where it could get hot enough to auto ignite at I think it's 1100 that is auto ignition. Yes straight ethylene glycol is in a similar area of ignition, but when mixed with 50% water that greatly changes figure. Then being in a sealed system none is going to get out easily. The more I learn of it the more I am considering using it myself.

A little autocross car that had a little flash, was a street legal Honda, but yes he was hot Rodded a little.
 
Yeah, I first heard of Evans from that race car, so I attributed it as for race application and set the product aside from my thought of street use not knowing what were the long term effects. It was from that event that Evans and others like it have been banned from SCTA events (all the land speed records and such). The fire suppression system was a safety requirement he had to have on the streamliner.

Like I was saying I think it's still safe to use people just need to be aware of it. The fire suppression system was a safety requirement he had to have on the streamliner.

Like I was saying I think it's still safe to use people just need to be aware of it. I just don't want to see anyone having a open Style reservoir overtop of or right next to exhaust or turbo where it could get hot enough to auto ignite at I think it's 1100 that is auto ignition. Yes straight ethylene glycol is in a similar area of ignition, but when mixed with 50% water that greatly changes figure. Then being in a sealed system none is going to get out easily. The more I learn of it the more I am considering using it myself.

A little autocross car that had a little flash, was a street legal Honda, but yes he was hot Rodded a little.

Thanks for the response 'Will L.' I have to check my old bills to see when it was I switched to the EVANS I'm thinking 3 years now and it's been vented w/zero pressure cap since then. I suspect because of the fender vents fast any fumes that could ignite from there may vent directly outside w/o exposure to the exhaust thinking now I'll install a 3 lb cap just in case and make sure the fire extinguisher is up to date too.
 
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