I'm going to install a new temperature sensor and gauge with an adjustable warning.
What temperature is in the warning zone?
When should you pull over and cool the engine?
When is it too late?
Going by the Detroit Diesel Series 92 Field Maintenance Recommendations (6/88), the maximum temp is 210 degrees F. whether it is a 170 or 180 degree thermostat, with an alarm set of 215 degrees. The thermostat operating range is 170 to 197 degrees. Personally, I stop and cool, or reduce gears when it gets to 200. There are lots of opinions, but you risk damage when temps get over 200 and up for whatever amount of time it takes to ruin your particular seals.
The worst thing you can do under those conditions is to pull over and let the engine IDLE, you need to go to neutral and bring the RPM up to increase oil pressure and fan speed and hold it there until the temps begin to decrease.>>>Dan
QuoteThe worst thing you can do under those conditions is to pull over and let the engine IDLE, you need to go to neutral and bring the RPM up to increase oil pressure and fan speed and hold it there until the temps begin to decrease.
I didn't know that... that could be helpful. I would have just left it idle slow and cool down slowly.
Seems the faster the engine speed the more heat it would produce. Yes, more fan speed too, but there must be a point where it doesn't make sense?
Anyway, I'll try to remember that. I have to pass over Jellico mountain today in 90 degree temps. I'm going to unhook my toad and have my wife drive it. But I'm still worried.
What your missing here is LOAD, diesels make heat under LOAD, and very little is made without it. So remove the load and get the oil and water working for you, about 1000 to 1200 RPM and hold it there.>>>Dan
The fast idle setting is enough to cool it while stopped, but downshifting to the next lower gear (if the transmission does not do it for you) will reduce the load on the engine to let it catch up. Jellico is not as bad as it looks, but it is fairly long, third gear should do it. There will be plenty of loaded trucks slowing you down anyway, and you won't be carrying 57 passengers. :)
What is Jellico-one of those little humps in the road on the east coast? Come out west for some real mountains (LOL)
Dave, not knowing the condition of your engine and how the cooling system has been maintained (antifreeze) I would pull over between 195* and 200* the spec's in a Detroit Field Service Manual are for new engines.
A 92 series can go to hell in a hand basket in a hurry @ 205* if the cooling system has not been maintained the seals on the liners and head can turn to mush
good luck
Quote
What is Jellico-one of those little humps in the road on the east coast? Come out west for some real mountains (LOL)
I've been driving my bus now for more than three years and more convinced than ever that these buses don't belong out west. Every post about a blown engine seems to be in Montana or some God-forsaken mountain.
Jellico is too much for my bus without a toad or hell-type heat. Today I'll go over during the night and let my wife drive the Tahoe.
LOL I drove my bus (8v92) all over the west for 15 years with no problems only break down was in the flat lands in Texas I broke a camshaft
Quote from: Tikvah on September 15, 2016, 08:48:52 AM... Jellico is too much for my bus without a toad or hell-type heat. Today I'll go over during the night and let my wife drive the Tahoe.
Weather Channel forecasts 81 degrees at 8PM and 71 at 10PM. Are you going north? Jellico grade is pretty steep for the East, and pretty long (ditto) -- probably the steepest on I-75 -- but it's not nearly as bad as I-77 at Fancy Gap (NC to VA, north of Winston-Salem and Mt. Airy "Mayberry"). Are you heading north or south? There are good places to stop IIRC (been a few months since I did it with a 4-wheeler) so unhooking and re-hooking the Tahoo shouldn't be a problem.
Drive it like you should and you'll be fine.
We're headed south tonight. Want to come push? :)
Make you wonder how trucks got over the hill in the 50's and 60's with a trailer grossing 58,000 lbs with 190 to 220 hp engines ;D and the GM gas rigs with the 261 CI chev engine or the 270 CI GMC truck engine.My dad ran trucks (80,000 lbs) from Houston to Alaska for years with the almighty 250 hp Cummins engines loaded with oil field materials
Quote from: Tikvah on September 15, 2016, 09:14:23 AMWe're headed south tonight. Want to come push? :)
I'm already south but you'll have no trouble, elevation is about 1000 feet at the TN/KY border and it goes up to about 2000 but it takes 6 miles to do it near Newcomb. Once you're at 2000 feet you run along without a lot of up and down until the grade down to Caryville (which is steep but you're going down it).
Reason I asked about heading is that I know of campgrounds and truckstops in KY; unfortunately, I'm less familiar with TN. There is an easy truckstop exit about 5 miles south of the border in TN at about 1970 feet, if you need a convenient, ez-off/ez-on cooling stop -- once you're there, the climb is mostly behind you. Might not be a good place to rehitch the toad, you still have the downhill at Caryville to come.
For crying out load, 2 thousand feet is like scratching your butt, I LIVE at 6 thousand and don't even notice till I start climbing.>>>Dan
Quote from: luvrbus on September 15, 2016, 09:42:32 AM
Make you wonder how trucks got over the hill in the 50's and 60's with a trailer grossing 58,000 lbs with 190 to 220 hp engines ;D and the GM gas rigs with the 261 CI chev engine or the 270 CI GMC truck engine.My dad ran trucks (80,000 lbs) from Houston to Alaska for years with the almighty 250 hp Cummins engines loaded with oil field materials
I did plenty of those hills with 262 (turbo'd 220) 5 and 4 speed transmissions 68,000. Not unusual to be down to a fast walking speed.
Quote from: Lee Bradley on September 15, 2016, 10:38:08 AM
I did plenty of those hills with 262 (turbo'd 220) 5 and 4 speed transmissions 68,000. Not unusual to be down to a fast walking speed.
You made it to top and over though ;D
You need to understand, I don't ever know the actual temperature of my engine. With no toad, in cool weather I went over that hill at about 20mph. Again never knowing the temperature.
Today I'm looking at that hill, no idea of engine temperature, towing a 6000lb Tahoe, in 90 degree weather.
You can brag about your Rocky Mountains, but without knowing what's happening to my engine in this heat I can't afford the chance. What would you do?
I only have one of those basic stock gauges.
LOL don't let Dan kid you we have grade on 68 between Bullhead and Golden Valley Az it is only 3700 ft to the top of Union Summit but it's a 6% grade climb for 12 miles try it on a 112* day.You really should get the temp gauge fix so you know for sure where you are at
Yes, hence this topic about setting up a new gauge with warning. But that won't happen before we drive tonight. :)
MCI gauges are usually accurate and reliable they just hard to read
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.busconversions.com%2Fbbs%2Findex.php%3Faction%3Ddlattach%3Btopic%3D30966.0%3Battach%3D28474%3Bimage&hash=9def9f6e096f2d56a91353c19d4e6f472ad22202)
There are two numbers 180 and 240
There is a thin red mark between the two numbers that I assume is 210
That means if I hit the thin red line I'm done owning a bus.
I've never seen it go above the top of the wide white line that's part of the 180 space. I assume the top of that line is 190
Hard to read? That's an understatement!
luvrbus,
I pulled that grade on 68 this summer, I wish it was only 112 degrees!
Matt
Quote from: Beluga Bus on September 15, 2016, 01:35:06 PM
luvrbus,
I pulled that grade on 68 this summer, I wish it was only 112 degrees!
Matt
I didn't want to mention the 120* lol that was the temp when we went up the grade in July
I was in Oregon two days ago at 8,000 feet on Rt. 395. Beautiful country up there but it was nice and cool so my engine temp was no problem.
I have heard that some folks have put an alarm or flashing light (I prefer a disco ball, but that is just me) on the dashboard to warm them if the temp gets too high, so you are on the right track. Not sure you really need a rheostat because there is a specific temperature which it should be set at, i.e. set it - and forget it. To have an adjustable knob on there may not be a good idea because I have seen kids get in my bus and twist all of the knobs on the dash and this is one knob you don't want touched.
This idea is great because if you miss the climbing temp, at least out here in the southwest when the road surface temp can be over 150 degrees the engine temp can sneak up on your really fast and before you know it your engine shuts down and you better be in the granny lane so you can get to the side of the road really fast. If you are in the Show-Off lane and your engine shuts down, it may be difficult to get to the right side of the road then you will be stuck in the fast lane putting out your cones and safety triangles. >:(
Lettuce know how it works out.
Quote from: Utahclaimjumper on September 15, 2016, 10:25:50 AM
For crying out load, 2 thousand feet is like scratching your butt, I LIVE at 6 thousand and don't even notice till I start climbing.>>>Dan
I have been out west many times up and over the continental divide; Jellico Mountain is still a respectable mountain in the grand scheme of things, and there are many mountain roads out east that have fooled over-confident western drivers. Altitude only affects the output of the engine, it does not change the grade.
Altitude has a great effect on the duration on the grade, it is a lot easier to pull a 6% grade from 1000 ft to 2000 ft than it is to pull a 6% grade from 1000ft to 8000ft. 20 miles of 6% grade is no joke.
Matt
Quote from: Tikvah on September 15, 2016, 12:23:09 PM
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There are two numbers 180 and 240
There is a thin red mark between the two numbers that I assume is 210
That means if I hit the thin red line I'm done owning a bus.
I've never seen it go above the top of the wide white line that's part of the 180 space. I assume the top of that line is 190
Hard to read? That's an understatement!
Ditch it! That one's even worse than my old Teleflex International gauge that also had very poor resolution. For less than $100 I solved it very simply by buying a Speedhut full-sweep gauge with stepper motor. With three times the resolution and probably much better accuracy, and some very cool night lighting, what's not to like? I also moved the all-important temperature gauge to front and center so it's directly in front of me. I like the Speedhut gauges so much I just bought one for transmission temperature, and I'll soon buy one for oil pressure - when I've installed that one, all my critical gauges will be full-sweep. No more quarter-sweep guessing games for me!
John
I crossed over Jellico last night at 4:00am pulling my Tahoe. I maintained 30mph and held it in 2nd gear.
The temp gauge never moved.
Now it's getting warmer outside and the hills are moving my gauge a bit, but I'll be parked in less than two hours.
Quote from: Tikvah on September 16, 2016, 07:11:33 AMI crossed over Jellico last night at 4:00am pulling my Tahoe. I maintained 30mph and held it in 2nd gear. The temp gauge never moved. Now it's getting warmer outside and the hills are moving my gauge a bit, but I'll be parked in less than two hours.
Thanks for the update, glad it was OK for you. I was wondering how it went. Will you be able to update the overheat alarm system and install an accurate temp gauge (as I- John suggested)? Longer term, what do you think you need for cooling system maintenance; do you foresee a need to check thermostats, radiator for circulation, fans and ducting, etc.
It makes me happy when I don't read a post that says "I was climbing a hill and a lot of white smoke came out of my exhaust". :)
my bet...everything is normal. the gauge stayed pegged in the go for it...
my guess is that the worry out weighs system efficiency :)
I changed my temp gauge the Moment I bought our bus. It's the most important gauge to me along with oil pressure and air pressure. But seriously, that should be high on the list. (https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fuploads.tapatalk-cdn.com%2F20160916%2Fd455086520c2b7baac68e0bb4187e101.jpg&hash=c68cbe68776ea6fe15596c238be26c54cbb303e7)
Sent from my iPhone using Tapatalk
Quote from: Oonrahnjay on September 16, 2016, 07:21:48 AM
...
It makes me happy when I don't read a post that says "I was climbing a hill and a lot of white smoke came out of my exhaust". :)
LOL, you mean like my post? :D
That's what did mine in, one of them damn big hills. Well that and crappily misadjusted valves. But I'm sure the hill had at least a little to do with it :o
That is why I plan most of my trips such that I spend more time going down hills rather than up. It saves the engine also saves no fuel mileage. ;D
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That is why I plan most of my trips such that I spend more time going down hills rather than up. It saves the engine also saves no fuel mileage. Grin
What goes down must come up