Cooling system stress test
Thread Starter
|
Laughing Gas
Joined: Mar 2006
Posts: 1,164
Likes: 2
From: Tri-Cities, TN
Cooling system stress test
Before I go replacing the radiator, I was wondering if anyone had an idea of a good way to test the cooling system? We will be pulling 12k +/- over high elevations and then across the south, so I don't want any surprises. I was going to just replace it to alleviate any concerns (already has a new water pump and Motorcraft thermostat). But then I found out it's time for a pump and injectors, and there goes my budget!
I could get 9k behind it and run a steep 2 mile grade about 35 miles from home, but I'm not sure that would be enough even with multiple runs as our ambient temps have dropped significantly in the past week (fall is starting here in the high country), and we will likely see much higher temps on our trip plus the increased load. And is it my understanding that 240* is the absolute maximum that is safe for the motor? Seems a bit warm to me, but all I really have to reference that to are gassers.
Thanks for any help!
I could get 9k behind it and run a steep 2 mile grade about 35 miles from home, but I'm not sure that would be enough even with multiple runs as our ambient temps have dropped significantly in the past week (fall is starting here in the high country), and we will likely see much higher temps on our trip plus the increased load. And is it my understanding that 240* is the absolute maximum that is safe for the motor? Seems a bit warm to me, but all I really have to reference that to are gassers.
Thanks for any help!
Elder User
Joined: Feb 2008
Posts: 867
Likes: 3
From: North Bend
35 miles is a long way to drive just to find a hill...dang. But hey it's an adventure!
240* would be the absolute top, assuming a 50/50 mix. And should never get there if your cooling system is good.
Get that 9k trailer and get after it.
2 miles isn't terribly long but with 9k should be a perfectly acceptable test. Start slow at the bottom of the hill and then pin it as hard as you can, blast the A/C to create more load on your system. Roll the windows down if it's too cold in the cab.
The fan should lock up good and roar. Temps should drop noticeably within a few seconds of the fan locking up.
240* would be the absolute top, assuming a 50/50 mix. And should never get there if your cooling system is good.
Get that 9k trailer and get after it.
2 miles isn't terribly long but with 9k should be a perfectly acceptable test. Start slow at the bottom of the hill and then pin it as hard as you can, blast the A/C to create more load on your system. Roll the windows down if it's too cold in the cab.
The fan should lock up good and roar. Temps should drop noticeably within a few seconds of the fan locking up.
Thread Starter
|
Laughing Gas
Joined: Mar 2006
Posts: 1,164
Likes: 2
From: Tri-Cities, TN
The fan definitely roars - on our last trip back from FL with a slide-in camper and a 40 mph headwind with 90* temps and running 70 mph, we listened to it for 300+ miles. I was seeing temps getting to 232* before I shut off the A/C. It would drop back to below 220, but it would creep back up once the A/C was back on. Once we got into traffic outside of Denver and the speeds dropped and it wasn't using as much boost, it cooled down some.
Elder User
Joined: Feb 2008
Posts: 867
Likes: 3
From: North Bend
Honestly just based on that info right there I'd at LEAST flush and refill the system. But it does sound like the radiator is corroded.
Just to be thorough: you have the fan shroud on, right?
When in good condition, a cabover camper shouldn't put the system though any trials, even at 70mph with a headwind. When that fan locks up its drawing so much air it's staggering. And when the radiator/system is clean, it'll cool down quickly rather than run on for hours.
Disclaimer: I don't have a transmission cooler(ZF5), and don't have working A/C, so my experience has less heat than yours might.
That said: as a comparison my pickup drags around a 4-5k trailer for my biz, and my fan NEVER locked up in 7 years. But my cooling system was clean enough for most of that that I never got in trouble unless I idled too long.
It would pull a little air but at best it was 30% of a full locked fan. I also live in the cascade foothills, nothing like the Rockies but it's quite hilly out here. I drive her as fast as I can up all the hills, until I hit 1100* EGTs then maintain it to the top.
Just to be thorough: you have the fan shroud on, right?
When in good condition, a cabover camper shouldn't put the system though any trials, even at 70mph with a headwind. When that fan locks up its drawing so much air it's staggering. And when the radiator/system is clean, it'll cool down quickly rather than run on for hours.
Disclaimer: I don't have a transmission cooler(ZF5), and don't have working A/C, so my experience has less heat than yours might.
That said: as a comparison my pickup drags around a 4-5k trailer for my biz, and my fan NEVER locked up in 7 years. But my cooling system was clean enough for most of that that I never got in trouble unless I idled too long.
It would pull a little air but at best it was 30% of a full locked fan. I also live in the cascade foothills, nothing like the Rockies but it's quite hilly out here. I drive her as fast as I can up all the hills, until I hit 1100* EGTs then maintain it to the top.
Thread Starter
|
Laughing Gas
Joined: Mar 2006
Posts: 1,164
Likes: 2
From: Tri-Cities, TN
Yes, it has the fan shroud. And it should be noted that this was a 3000 pound, 11' high slide-in, and I was constantly using 4-6 pounds of boost with EGTs running 650-900. So it was working hard. We actually had to stop for the night in CO as 80 in WY was closed to light, high-profile vehicles (the very definition of which we were driving) due to 60+ gusts, so that shows the headwinds we were fighting across Kansas and Colorado. And since I have seen semis blown over on that road, we decided to wait.
We have decided to increase the budget for work on the truck, so new radiator it is. It easier and quicker than any other solution.
We have decided to increase the budget for work on the truck, so new radiator it is. It easier and quicker than any other solution.
Lead Driver
Joined: Apr 2008
Posts: 6,945
Likes: 13
Not actually all that uncommon. Those tarp trailers are really bad about it because they act like sails.
Not that it really helps you much, but my radiator IS corroded. Fan works like a champ, and i have to back out substantially up a 5 mile 6% grade empty to not over heat. Anything over 750ish on the pyro and it will start climbing if its warm out. Thankfully, its getting boiled when the new engine is ready to go in.
Not that it really helps you much, but my radiator IS corroded. Fan works like a champ, and i have to back out substantially up a 5 mile 6% grade empty to not over heat. Anything over 750ish on the pyro and it will start climbing if its warm out. Thankfully, its getting boiled when the new engine is ready to go in.
Trending Topics
Thread Starter
|
Laughing Gas
Joined: Mar 2006
Posts: 1,164
Likes: 2
From: Tri-Cities, TN
Empty on the highway, it won't break 194 with A/C on and 95* temps. Even pulling 16k at 60 mph at 75* doesn't bother it. It's only when loaded and hot out that it starts to climb.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Thread
Thread Starter
Forum
Replies
Last Post
lwarrior1016
1999 - 2016 Super Duty
20
Jul 28, 2016 09:50 PM