• Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!

  • Microsoft MSN, Live, Hotmail, Outlook email users may not be receiving emails. We are working to resolve this issue. Please add support@steelsoldiers.com to your trusted contacts.

Replacing Coolant Reservoir Cap - 16 LBS or 15LBS?

54
41
18
Location
NORTHEAST WYOMING
Hey guys,

I am looking to replace my coolant reservoir cap on my M1123. I am pretty sure that the vehicle year is 2000 or 2001. I would like to go with a mil grade cap that would be the best one for my vehicle. Current cap on vehicle says 16lbs but I read online that some people recommend the mil grade 15lbs. Which one should I go with? 16lbs or 15lbs? And is it really important as far as which one to go with, or would either one work well?

As always thank you so much for the help. You all are awesome and a great help! I am very grateful to have so many smart and experienced people in this amazing forum!
 

Maxjeep1

Well-known member
Steel Soldiers Supporter
1,338
1,916
113
Location
Las Vegas Nevada
Convert to Evans waterless coolant and you don’t need a cap or hose lamps. Lasts forever and it doesn’t corrode anything. I’m doing it soon. Had it in my H2 for 3 years now and I’m very happy with it. I don’t think it makes a difference with your 1pound difference
 

papakb

Well-known member
2,285
1,185
113
Location
San Jose, Ca
Pressure in the system raises the boiling point of the coolant and with a system where the fan cycles at 230 degrees you want the highest pressure you can reasonably use without blowing something out so I'd go with the 16# cap. That's what all the early HMMWVs had on them. And the H2 is just a Chevy Tahoe in drag. Let's compare apples and apples here.
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
4,397
4,181
113
Location
Brentwood, Calif
Pressure in the system raises the boiling point of the coolant and with a system where the fan cycles at 230 degrees you want the highest pressure you can reasonably use without blowing something out so I'd go with the 16# cap. That's what all the early HMMWVs had on them. And the H2 is just a Chevy Tahoe in drag. Let's compare apples and apples here.
230 is a bit high…220 is where you want to be.
 

Maxjeep1

Well-known member
Steel Soldiers Supporter
1,338
1,916
113
Location
Las Vegas Nevada
Pressure in the system raises the boiling point of the coolant and with a system where the fan cycles at 230 degrees you want the highest pressure you can reasonably use without blowing something out so I'd go with the 16# cap. That's what all the early HMMWVs had on them. And the H2 is just a Chevy Tahoe in drag. Let's compare apples and apples here.
Pretty sure the cooling system functions in the same way on the Tahoe and consists of the same basic items that are on the Hmmwv. I would rather have a lifetime coolant that has a 370 degree boiling point and builds zero pressure in the system and will never corrode. Probably helps the hot spots in the engine because it doesn’t create steam. You probably can’t get it in Kalifornia anyways. It’s strange driving a few hours and popping the hood on my Tahoe and pinching the radiator hose closed and taking the cap off while it’s at operating temperature and you have zero pressure. Everyone can use whatever they want. I need to go, someone just paged me and I need to stop at a pay phone and call them. Lol
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
4,397
4,181
113
Location
Brentwood, Calif
Pretty sure the cooling system functions in the same way on the Tahoe and consists of the same basic items that are on the Hmmwv. I would rather have a lifetime coolant that has a 370 degree boiling point and builds zero pressure in the system and will never corrode. Probably helps the hot spots in the engine because it doesn’t create steam. You probably can’t get it in Kalifornia anyways. It’s strange driving a few hours and popping the hood on my Tahoe and pinching the radiator hose closed and taking the cap off while it’s at operating temperature and you have zero pressure. Everyone can use whatever they want. I need to go, someone just paged me and I need to stop at a pay phone and call them. Lol
If it’s so great, why aren’t the manufacturers using it? I’ve been a diesel mechanic for over 30yrs, not a gimmick fan.
 

Maxjeep1

Well-known member
Steel Soldiers Supporter
1,338
1,916
113
Location
Las Vegas Nevada
If it’s so great, why aren’t the manufacturers using it? I’ve been a diesel mechanic for over 30yrs, not a gimmick fan.
Cost? Because you only need to buy it once? Because it doesn’t corrode and they can’t sell you new parts? I think if you tried it you would like some of the benefits. I was skeptical about it but I thought I would give it a try while I was adding my becool radiator and had my cooling system apart. I don’t think it can freeze at any temperatures that we experience. I just like the fact that you will never have corrosion issues and it lasts the lifetime of the vehicle. I’m sure you have lots more experience with everything than I do and I truly mean it. That being said it doesn’t make me wrong about something that I have personally used for 3 years now. 50/50 and regular maintenance will have nearly the same results but I would rather do it once and never have to worry about it again.
 

papakb

Well-known member
2,285
1,185
113
Location
San Jose, Ca
I don't know but Black Dog Customs says the fan turns on at 220-230 degrees. The -10 manual says "over 215". So go figure?


I need to go, someone just paged me and I need to stop at a pay phone and call them. Lol And your replying on Steel Soldiers?
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
4,397
4,181
113
Location
Brentwood, Calif
I few more issues than cost…several of these are not ideal IMO.

1. The cost of the waterless coolant is much higher.
If you were to use a standard coolant or antifreeze in your vehicle, then the product cost would be around $20 per gallon. The cost of the waterless coolant from Evans, which is the primary supplier of this option, is about $40 per gallon. If you’re using a big-bore diesel engine with your truck, semi-trailer, or another large vehicle, the difference in price for your coolant needs may be $400+ if you choose the waterless option.


2. There are availability concerns to think about with waterless coolant.
If a slow leak occurs with your vehicle, then you can make it home easy enough before repairing the issue. Just stop at any store, purchase replacement coolant, then make sure your reserves never get too low. That option disappears for you when using waterless coolant. Availability is not as widespread as traditional antifreeze or coolant options because only authorized service providers have the product. Adding water eliminates the benefits of going waterless too.

That means you must stock up on the product when you make the conversion to the waterless coolant. If you use it in your everyday vehicle, then you’ll need to carry some with you at all times. Without plenty of extra, you’ll find the recovery costs of popping a hose can become an unpleasant surprise.

3. Heat isn’t moved as effectively with waterless coolant.
Even Evans Waterless Coolant offers a lower specific heat rating, which means a water-based product will create a faster result in comparison. Compared to water, the specific heat capacity falls into a range between 0.6 to 0.7. That’s why the traditional coolant technologies have been around for so long. The coolant creates a higher boiling temperature for the water, providing you with a layer of protection which is adequate unless the vehicle overheats. Some vehicles run cooler with a waterless coolant, especially if they are equipped with a high-performance engine. Others do not.



4. Engines typically run hotter at the cylinder heads.
Although the overall process creates a cooler engine for many vehicle owners, using a waterless coolant does make an engine run hotter at the cylinder heads. For a high-performance engine, the issue could change conditions by over 100°F. The stabilized coolant temperatures are increased by at least 30°F when the conversion takes place as well when compared to a 50/50 or traditional coolant. You’re also faced with an inhibitor disposition on aluminum surfaces, which may be problematic for some radiators.



5. There is a conversion cost to consider with going waterless.
If your vehicle has not received coolant as of yet, then the cost of a waterless coolant is only the product expense. When you’re converting from a traditional coolant, however, then your system must be purged. Over 97% of the original coolant must be removed from the system for the waterless coolant to be sufficient. If you do not achieve that rate of success, then you lose the corrosion-resistance benefit. The cost of purging the system varies per location, but it typically falls into a range between $250 to $400.



6. Waterless coolant may reduce your horsepower rating.
When a full conversion to waterless coolant occurs, owners notice a small dip in the horsepower possible from their engine. Some high-performance engines see a drop of 5% or more. At the same time, the fuel octane requirement for the engine increases by up to 7 points, which further reduces performance if a shift in gasoline quality does not happen. The hidden costs of these issues to correct them further increases the overall expense of switching from a water-cooled system to this product.



7. It will absorb water when allowed to sit out in the open.
When you use a waterless coolant, it is essential to remember that the product is hygroscopic. That means it offers the capability of absorbing moisture from the surrounding environment. It will even pull water from the air if you allow it to sit outside. Most cooling systems do not have air exposure concerns, so the absorbing nature of the fluid is not an issue within the vehicle. If you’re performing maintenance on your cooling system, however, then you’ll need to place the fluid in a tightly-closed container to prevent it from being corrupted.


8. There are flammability concerns in high-performance settings.
“Only dealt with that stuff one time,” is an observation written on a tech talk forum about waterless coolant. “Guy dumped it on the starting line and made a full pass that was a 3-hour clean-up. Worst stuff I have ever cleaned and extremely slippery.” There are also flammability issues reported with waterless coolant when exposed to high-heat situations on racetracks and other high-performance areas. Although reviews on this potential disadvantage are mixed, the issue should be approached with caution at the very least.



9. The fan on your vehicle may start operating continuously.
Because waterless coolant changes the temperature profile of your vehicle, some owners may find that their fan triggers on continuously because of the heat at the engine. Although the waterless coolant provides better protection, you may need to reprogram the temperature settings of your fan to prevent this issue. Some owners may also change their engine timing to prevent knocking after a switch to this product and look at the specs of their water pump since the viscosity of waterless coolant is a little different.



10. You may be forced to purchase by mail.
Even though you can find waterless coolant products online, only authorized dealers are permitted to sell the product for Evans (and similar rules apply to other manufacturers). If you purchase your product from a retailer who is not authorized, including online companies, then the warranty coverage offered by the product does not apply.
 

Retiredwarhorses

Well-known member
Steel Soldiers Supporter
4,397
4,181
113
Location
Brentwood, Calif
I don't know but Black Dog Customs says the fan turns on at 220-230 degrees. The -10 manual says "over 215". So go figure?


I need to go, someone just paged me and I need to stop at a pay phone and call them. Lol And your replying on Steel Soldiers?
there is “actual“ and than there is “indicated” as we say in the aviation world.
if Your engagement is at 230, you should be replacing your thermostatic switch and or temp gauge.
At my shop, every truck that comes in “several weekly” from Barstow, get a road test, the No.1 test is the fan clutch engagement and disengagement test, disengagement test because it’s all to common once engaged the fan won’t disengage, next up is if the system is building proper pressure.
 

Action

Well-known member
3,576
1,557
113
Location
East Tennessee
I’m hung up on the “no hose clamp” comment. How can you have zero pressure in the system? Let’s say the water pump creates 10 psi of pressure. If it can pull in at the same speed, the pressure would equalize. When the water flow path decreases in size, the pressure increases. So if it comes out of the water pump at 10 psi in a 5/8” tube, wouldn’t the pressure be higher at any point where it is less than 5/8” wide?
 

Maxjeep1

Well-known member
Steel Soldiers Supporter
1,338
1,916
113
Location
Las Vegas Nevada
I’m hung up on the “no hose clamp” comment. How can you have zero pressure in the system? Let’s say the water pump creates 10 psi of pressure. If it can pull in at the same speed, the pressure would equalize. When the water flow path decreases in size, the pressure increases. So if it comes out of the water pump at 10 psi in a 5/8” tube, wouldn’t the pressure be higher at any point where it is less than 5/8” wide?
I was referring to the fact that it doesn’t build any additional pressure from heat. I was not in anyway suggesting that you throw away all your clamps. It’s weird how I can squeeze my upper hose flat at operating temperature and that was when I thought that the clamps aren’t doing near as much Work as with regular coolant.
 

Micmada

Active member
159
211
43
Location
Florida
Pretty sure the cooling system functions in the same way on the Tahoe and consists of the same basic items that are on the Hmmwv. I would rather have a lifetime coolant that has a 370 degree boiling point and builds zero pressure in the system and will never corrode. Probably helps the hot spots in the engine because it doesn’t create steam. You probably can’t get it in Kalifornia anyways. It’s strange driving a few hours and popping the hood on my Tahoe and pinching the radiator hose closed and taking the cap off while it’s at operating temperature and you have zero pressure. Everyone can use whatever they want. I need to go, someone just paged me and I need to stop at a pay phone and call them. Lol
I like the waterless idea regarding corrosion, but I want some pressure to keep that head gasket down. I had a bunch of rust so will probably switch to Evans for a while… will see.
 

Mogman

Moderator
Staff member
Moderator
Steel Soldiers Supporter
6,930
9,587
113
Location
Papalote, TX
There is a celebrity that has a very LARGE automobile collection and in many cases only one exist in the whole world and he advocates the water less coolants, makes perfect sense for him, they never get far from the shop and zero corrosion worry for something that can be worth upwards of a million bucks just makes sense.

For the rest of us not so much.
 
Top