| Author |
Message |
FAST FRED (209.26.87.78)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, November 10, 2001 - 8:26 am: | |
On our ride South this year , I was driving with the "new " style cast Alluminum valve covers.
I had good gaskets and seals on the stamped steel units , but these aluminum covers reduced the oil flow from 500 miles per quart { which I thought was normal} to a quart in 1300 miles.
This was such a change I sent the oil out for a DD lab test , to see if there was fuel making up for the lack of oil consumption.
Happily , its the "new " style valve covers!
There was still some DD oil on the boat trailer we tow , so the usual DD preserving the tow with a thin coat of oil still works.
Might help somone with an early engine that hasn't been changed yet.
I have also found that using a cheap level , on the rear bumper helps in checking the oil level, with the long oil pan a small difference in level changes the oil reading a quart or two.
FAST FRED |
Bill Butler (63.15.111.99)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, November 10, 2001 - 5:37 pm: | |
Hey Fred: I have trouble telling where my oil level is within several quarts. How can you tell when you are a qt low. Is it that important? |
FAST FRED (209.26.87.28)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 6:31 am: | |
Bill., On my dipstick there is a full and low mark.
If the engine is level across the rear ., its pretty simple.
Do you have stock dip stick with both lines?
The full and low are one gallon apart so guessing the quantity to fill is fairly easy.
I prefer to run at the full line as much as I can.
This gives the most oil for cooling ,and cleaning the engine , and a sudden RISE in the level could signal a broken jumper, a very dangerous condition .
FAST FRED |
Bill Keller (209.173.120.236)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 8:00 am: | |
All the trucker over the years that run DD run
them just above the add mark, that includes myself
Uses less oil. add more seams to push it out. Just
my experience and has worked for me for over 35yrs
what ever works for you. |
Bill Butler (63.15.111.167)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 12:07 pm: | |
OK Fred,what on earth is a"broken jumper"? A wounded parachutist? Their dangerous.
I have the high and low horizontal lines on my dipstick. It appears my oil pressure is better at low speeds if I have more, rather than less oil in the pan.
Another subject. When we had some work done at Roseburg, Ore. they informed me not to let a DD idle at slow rpms, like a dummy I didn't ask why.
Any clue?
Bill Butler |
Scott Whitney (63.151.69.220)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 12:44 pm: | |
Idling a DD for any length of time on fast or normal idle is bad, bad. The DD were designed to run at optimum efficiency at full load. So at idle they are only marginally effective. Better to shut down unless you are just at a stoplight. Once she is aired up, take her on the road. |
RJ Long (24.127.8.58)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 2:20 pm: | |
To further add to what Scott said, the 71 series only run about 4-5 psi of oil pressure at low idle. Or at least, that's what the gauges seem to show.
"Fast idle" is about 900 rpm, and the oil pressure is around 25-30 psi at that speed, much better lubrication. (Also provided much more juice from the alternator to power all the A/C stuff back in it's commercial seated days.)
"Broken jumper" refers to the fuel line jumpers in the head, next to the injectors. When one breaks, or starts leaking, your oil level mysteriously "goes up" - as you're filling your crankcase with diesel fuel!
HTH,
RJ |
Richard Bowyer (Drivingmisslazy) (65.207.109.158)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 5:09 pm: | |
But what about the hundreds of truckers that sit overnight in the truckstops with their engines idleing? This has been going on for years and I am sure a lot of them have been 2 stroke DD's. Is this an efficiency thing or does it really damage the engine? Due to very cold outside temperatures I have had to idle my 8V92 overnight a few times because I was afraid I could not get it started the next morning and I do not believe it really did any harm. I would really like to have some real truckers opinion on this matter.
Richard |
Jim Ashworth (Jimnh) (172.150.240.200)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 6:09 pm: | |
As a commercial bus driver, I have idled an engine with a cracked head and no antifreeze (removed so it wouldn't contaminate the oil and wreck the engine) overnight in freezing temps. NOT MY BUS. I did what I was told! DD idling can accumulate unburnt fuel and oil in the airbox which COULD lead to a runaway engine on acceleration if idled for a long time. Low idle oil pressure should be 20 psi, but an older engine will have lower. Low oil shutdown is about 5-7 psi. As to the truckers, refer to above--- NOT MY ENGINE!! Now, if it WERE my engine... Don't idle it and don't run it with cracked heads... fix the darn thing in the shop so you don't have to fix it on the road at the mercy of some shop that just sees $$$$$$'s coming in the door.
Jim |
Scott Whitney (63.151.69.220)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 9:02 pm: | |
Hi Richard,
The following pretty much dovetails with what Jim explained. . . what DD told me (and everyone else in the seminars in Laughlin) is there are two reasons truckers idle engines for long periods:
1) They don't pay for maintenance
2) They don't pay for fuel
Scott |
DrivingMissLazy (65.207.109.80)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 10:21 pm: | |
OK. So now I know. Thanks, Guys.
Richard |
HondoJoemc5 (63.11.98.186)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 11:10 pm: | |
Hey FF-
Straiten me out here. You know I must be new!
I know my steel valve covers leak and I have new gaskets in hand to change to hopefully stop leak.
You mentioned your old covers had good gaskets & seals. I assume this means they did't leak.
So how can installing new type aluminum covers lessen oil consumption?? I want some of them!
Can you tell me where to get 'em?? Thanks HJ |
Tom Caffrey (Pvcces) (12.146.33.157)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, November 11, 2001 - 11:19 pm: | |
Bill, we have been getting Heavy Duty Trucking magazine for years, and they have spent a lot of time on this issue.
The main problem is that the engine overcools. This is true of four strokes, as well, but it's worse with the Detroits.
We have found that if there is some load on the engine, it helps maintain the heat inside of them. For generating or air conditioning purposes, a very fast idle will overcool them more than a slower fast idle.
Think in terms of enough fuel burned to generate some heat, but not enough to lug the engine. I think that led to the specified fast idle on these buses. If you are not trying to get some work out of the engine, you are better off shutting it down.
Part of the problem with all those trucks running all night was ignorance, part of was convenience and part of it was no alternate source of heat and power, especially if it was really cold.
Many trucks today have inverters and generators, so they are turning them off more. I think that that equipment probably pays for itself pretty readily in today's environment.
Tom Caffrey PD4106-2576 |
Bill Butler (63.16.0.185)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 14, 2001 - 9:39 pm: | |
An older, experienced bus man informed me also that oil is squirted up into the head of the pistons to cool the piston. He expressed how important it is to keep the oil pressure high enough to perform this function. My oil gauge only registers at 25lbs and 50lbs, no in-between,
so I have no way of knowing what my idle pressure is. Thanks to all who particapated in this discussion. I find it very educating and interesting. |