What the Heck Happened?

[55 Fargo]

Factory tested the designs at max BHP in 50 hour tests. Seems like if the engine can't run at max throttle for 50 hours then something is wrong.

Well yes in a perfect world, and under controlled condtions with brand spanking new engines, not 60 year old rebuilt engines.

Todays gasoline with modern ethanol enhanced corn juice, cannot be helping matters either, let's say under hood temps were rising, fuel gets really hot, and a lean condition is created, that with super high RPM and major load would be maxing to the outer limits.

Or perhaps an issue with a simple thing like a lower rad hose collapsing allowing engine temps to rise, allowing a very hot under hood condition allowing gas to boil and very lean condition.

Whatever the initial cause, it appeared once engine RPM was reduced, as well as the load, this engine ran a whole lot better...

Edited April 14, 2015 by Fargos-Go-Far

[Merle Coggins]

Merle - what about advance? Is the Distributor advancing properly (vacuum and weights).

 

Good though John. I meant to check that too but forgot last night. I have an advancing timing light so I can dial up the advance while revving the engine to check it, but I didn't. But since everything came back to normal after reducing the load against the strong wind I would have to say that all is OK there. I know it was good the last time I checked it and I don't notice any performance difference aside from that one incident.

 

Fred, I have not pushed it up to 70 again since that incident, but that morning it was fine at those speed the couple times I approached it. I do believe it was just an overload situation, much like climbing a steep grade in too high of a gear. I should have backed off sooner so as not to allow it to get that hot, but my the time I noticed it I was past one exit and it was a few miles to the next one. I had just come out of a construction zone where the speeds were ramping up past 60, so before that I hadn't noticed anything wrong, except for the strong wind. Apparently the load was too great to get to the next exit and keep up with traffic. It was mid 60's that day so ambient temp wasn't an issue. I've pushed it faster than that in much higher ambient temps and never had any issues with engine temp. 

 

Lesson learned.

Edited April 14, 2015 by Merle Coggins

[Dave72dt]

I've had the same thing happen when hauling machinery. Really stiff wind, heading directly into it, I couldn't run in high gear and my temps kept going up. Had to drop down a gear. It was nice when a semi passed me. It blocked the head wind enough the truck would actually surge forward until the semi no longer blocked the headwind effectively. Once I could change direction and have a sidewind, I could once a gain run in high gear with no problem. I simply didn't have enough horsepower in that particular scenario.

[Jeff Balazs]

Interesting. I reckon the old pilothouse isn't all that aerodynamic either. I wonder if dropping the tailgate would have made a difference? I used to do that when heading out to the desert over the Cajon Pass. Always seemed like it made a difference. It is quite often one very windy section of highway. Guess I will find out soon enough.

 

Jeff

Edited April 15, 2015 by Jeff Balazs

[Young Ed]

Interesting. I reckon the old pilothouse isn't all that areodynamic either. I wonder if dropping the tailgate would have made a difference? I used to do that when heading out to the desert over the Cajon Pass. Always seemed like it made a difference as it is quite often one windy section of highway. Guess I will find out soon enough.

 

Jeff

 

Merle has a bed cover that should take care of that

[Jerry Roberts]

According to ' Car Talk '  , a truck tail gate in the closed position is more areodymatic (sp?) than a tail gate in the open position . Something about forming an air pocket . 

[TodFitch]

Interesting. I reckon the old pilothouse isn't all that aerodynamic either. I wonder if dropping the tailgate would have made a difference? I used to do that when heading out to the desert over the Cajon Pass. Always seemed like it made a difference. It is quite often one very windy section of highway. Guess I will find out soon enough.

 

Jeff

Back when I had a pickup truck I had heard that. I measured gas mileage carefully with the tail gate both down and up and there was no difference. If the mileage does not change then I'd expect that the power requirement did not change.

[Jeff Balazs]

According to ' Car Talk '  , a truck tail gate in the closed position is more areodymatic (sp?) than a tail gate in the open position . Something about forming an air pocket . 

I am not sure if that is true when you add the head wind into the equation. It always seemed to feel like it rode and/or tracked better in high winds with it down. All I have is a seat of the pants impression on this. We get a lot of high winds here.......called Santa Anas.....and in those at speed I will always trust what I can feel.

 

Jeff

[HanksB3B]

Hi Merle that sounds familiar....I didn't have a head wind...rather a long drive and then up into the Malibu hills when it happened. Incidently, this video is a good example of what happens...when you are with a wife as opposed to having a girlfriend along for the ride....

 

http://vid983.photobucket.com/albums/ae317/hanksb3b/Videos/201101151438573.mp4

 

Hank 

 

Ever hear of the term "heat soaked engine" I think it does have to do with fuel boiling over or something like that..Glad you made it home!

Edited April 15, 2015 by HanksB3B

[TrampSteer]

I wonder now if the mechanical action of the fan, moving forward at 60mph+headwind, got to a spot where it stopped acting like a fan.

[Don Coatney]

Radiator efficiency may have something to do with it too. I once was caught behind a farm tractor going up a 3-4 mile long steep hill. Second gear at less than 20 MPH. With no head wind my engine temperature rapidly increased. Once I got over the hump and back to speed my engine temperature dropped back to normal. With my new 3 core aluminum radiator I don't think I would have such a problem as the radiator efficiency is greatly improved.

[Jeff Balazs]

Don what you are talking about is a radically different scenario than running at speed into a headwind. You just were not getting enough air through your radiator. In the scenario Merle had the combined speed of the truck and the wind should have been something like 90 mph. That should be plenty of air moving through the radiator if all else is well. I have often wondered why Dodge redesigned the front of these trucks. It certainly was one of the biggest changes in these trucks over the production span. Could it be that the earlier front section like on Merle's truck was not as efficient as it needed to be under certain situations?

 

Jeff

[Young Ed]

I would think the new front grill was purely marketing.

[Jeff Balazs]

Ed;

Maybe ?.....but I know which one looks like it would be more efficient at channeling air through the radiator.

Funny stuff can happen at high wind speeds. Sometimes all it takes is a few more mph to change something that is perfectly fine into something that is very bad.

 

Jeff

[Merle Coggins]

My cooling system is in good condition, the bare block was power washed inside and out thoroughly during the rebuild, and the radiator has been re-cored with a good quality tube and fin core. Heating has never been an issue since I've built this truck. Even driving around in mid to upper 90's has not given any issues with the cooling system. I do agree with Jeff that the B3 / B4 grill appears to have better air flow through to the radiator than a B1 or B2. I would like to think that at that speed, with the wind, I would have had plenty of air flow across the radiator, but maybe that was a factor to add to the high load. Either way, I know now that in that situation it's time to back off, get off the freeway, and find a more relaxed route.

 

Merle

[Jeff Balazs]

Merle;

I have no doubt your truck is in tip top shape. I suppose going into a strong head wind might be very similar to pulling a very long grade. You are probably correct about this just being too much for one of these trucks and the power they have available. I am going to have to see how mine behaves when faced with a similar situation. I have a slightly higher final ratio in mine too.

 

On a side note maybe we can get Tim to do a few comparison runs at Bonneville? Some with a B1/B2 nose and some with a B3/B4 nose. It would be interesting to see if it made any difference.

 

Jeff

[48Dodger]

Elevated work loads equals heat. Water cavitation from increased heat will slow the motor down by causing a drag on the pistons in the hole. I've had power loss and locked pistons when heat was uncontrolled (racing). As air increases in speed through the radiator (baffled, think venturi) temps can drop dramatically. Even a simple cone directed to the radiator can save your day. 

 

48D

[Jeff Balazs]

Elevated work loads equals heat. Water cavitation from increased heat will slow the motor down by causing a drag on the pistons in the hole. I've had power loss and locked pistons when heat was uncontrolled (racing). As air increases in speed through the radiator (baffled, think venturi) temps can drop dramatically. Even a simple cone directed to the radiator can save your day. 

 

48D

Yes....so how about an effeciency test of the two different front ends the next time you go to Bonneville? I think the B3/B4 nose is going to work better at speed than the earlier design. Could even raise your top speed?

 

Jeff

[MBF]

One thing that I didn't see considered here was the formulation of the new gas with the ethanol.  I took my 78 1/2 ton with a slant six on a 300 mile trip to pick up a John Deere LUC power unit.   The slant was newly rebuilt about 10K ago.  It ran fine on the way up with the truck empty, but on the way back it started pinging pretty badly.  I did a fillup with a higher octane gas, but still ended up backing off the timing a couple of degrees in a rest area.  When I bought the truck 34 yrs ago I could tow a 1700 lb boat with three guys, and two full sets of scuba gear w/o any pre-ignition, now I'm running less base timing (about 5 degrees btdc instead of the 10 I used to run) and getting less mileage too.  Talking to engine builiders I know, the higher percentage of alcohol that is actually showing up in some gas is causing damage to even new car engines.  I'm wondering if that played a contributing factor given the headwind causing the higher operating temps.  Mike

[4852dodge]

Sounds like the alcohol content is causing a lean condition which in turn genearates more heat.  Enlarging the main jet should help the problem.  Then the timing can be returned to spec.

[55 Fargo]

One thing that I didn't see considered here was the formulation of the new gas with the ethanol.  I took my 78 1/2 ton with a slant six on a 300 mile trip to pick up a John Deere LUC power unit.   The slant was newly rebuilt about 10K ago.  It ran fine on the way up with the truck empty, but on the way back it started pinging pretty badly.  I did a fillup with a higher octane gas, but still ended up backing off the timing a couple of degrees in a rest area.  When I bought the truck 34 yrs ago I could tow a 1700 lb boat with three guys, and two full sets of scuba gear w/o any pre-ignition, now I'm running less base timing (about 5 degrees btdc instead of the 10 I used to run) and getting less mileage too.  Talking to engine builiders I know, the higher percentage of alcohol that is actually showing up in some gas is causing damage to even new car engines.  I'm wondering if that played a contributing factor given the headwind causing the higher operating temps.  Mike

Yes well, I mentioned the modern "corn booze" fuels in post 17 and 26, this fuel will have an effect, that's for sure.

[Jeff Balazs]

The fuel thing may certainly have something to do with what happened. Having lived in a hot climate my whole life I am used to dealing with the effects of excessive heat. One of the things I learned many years ago was to overbuild the cooling system in my vehicles. Putting in an over sized radiator can make a huge difference in how well an engine will run when put to the test. If the cooling system is truly working at it's best you shouldn't see much of a temperature rise even under heavy loads. Most of us desert rats can attest to this.

 

Jeff

[John-T-53]

Sounds like the alcohol content is causing a lean condition which in turn genearates more heat.  Enlarging the main jet should help the problem.  Then the timing can be returned to spec.

 

That's what had to be done on my "fusie" Chrysler with 440 / thermoquad carb. The new gas just wouldn't allow the engine to be tuned 100%. It had a lean miss. So larger main jets helped it out. I wouldn't say the new gas is the culprit of Merle's experience, however it sure as hell didn't help!

 

It also supposedly attacks lead solder (like on your floats)...

 

It's really too bad we have no choice in the fuel we have to buy. Especially considering the taxes imposed on it.

[55 Fargo]

Just got back from a nice drive, it is cold here 45f, 25-30 mph northwest wind. I had fun drove both town and country, and drove her like I stole her, pedal to the metal a lot.

I did find though on the last leg of the drive on the highway, a super strong cold wind, had to really push her to get up to 65 mph, she is a bit sluggish with 3.23 gears and a strong head wind. I would equate going against a very strong wind is like hill climbing a lot of load on the crank.

I had a blast driving tonight.....PS Winnipeg Jets are going Duck hunting tonight at the MTS center....yeehaww

[Jeff Balazs]

Just got back from a nice drive, it is cold here 45f, 25-30 mph northwest wind. I had fun drove both town and country, and drove her like I stole her, pedal to the metal a lot.

I did find though on the last leg of the drive on the highway, a super strong cold wind, had to really push her to get up to 65 mph, she is a bit sluggish with 3.23 gears and a strong head wind. I would equate going against a very strong wind is like hill climbing a lot of load on the crank.

I had a blast driving tonight.....PS Winnipeg Jets are going Duck hunting tonight at the MTS center....yeehaww

I reckon this thread has an appropriate title for you now. You know it's funny here we are in what can only be described as an irrigated desert. And we have hockey .....and here hardly anyone cares about hockey. Seems very odd to me that we even have teams. It is not like any of us grew up playing the game. I suppose hockey is here because we have so damn many transplants? Go Ducks?......nah that is just not going to happen. Unless they go.....and take a few million people with them.

 

Did you get a rise in temperature as you were running into the headwind? That is the real question.

 

Jeff