pyrometer gauge

[Petervs]

Jon, you said "As much as I like the Series 60, I don't see it as an improvement over the 8V92 except for fuel mileage."

You are full of prunes here. The Series 60 is better because:

A. No worries about overheating ever.
B. More torque, run it at any rpm without worries
C. Designed in the late twentieth century.
D. Any shop can work on it, but none ever need to because they do not quit.
E. 25% fuel mileage improvement is nothing to sneeze at
F. No more blown exhaust manifold gaskets.
G. No more DDEC computer in the valley under the turbo where it is so hot it takes a fuel cooled heat exchanger to prevent the computer from melting
H. Will run the life of the chassis, the 8V generally need overhaul at 500,000 miles give or take.
I. Jake Brake has more power on the Series 60

Seriously Jon, would you trade back to an 8V?

And for how long will there actually be parts available for them? Sure there will always be specialty shops that work on them, but Detroit Diesel has been bought and sold a few times now, and they certainly do not make serious profit on these old engines. Other than our busses, a few stationary applications and a bunch of boats these engines are no longer in common use on the highway. The truckers switched to the modern engines long ago for the same reasons.

Detroit will quit supporting the 8V some day, as soon as they can in my opinion. On the other hand, the Series 60 will be supported for the rest of my lifetime I am sure.

Reconsider maybe?

[gmcbuffalo]

Is there only one level row of manifold bolts? I don't see any staggered bolts or top and bottom ones.
Greg

[Jon Wehrenberg]

Peter, In the context of what you say you are almost completely right. I meant the engines were equal as far as performance in pulling the hills. But you are right on most of your points.

However, I never had overheating problems on my 8V92.

I could work on my 8V92 without disassembling my bedroom.

The lugging ability of the Series 60 (which is over rated) is more than offset by a 5 speed transmission that works the 8V92 engine in the full 1500 to 2100 RPM range. The Series 60 and six speed combination shifts smoother, but it lugs down in the default mode to the point at which downshifts do not let you accelerate back up to speed but only hold the reduced speed. To get the most out of the Series 60 / six speed combination you have to go to performance mode and tolerate harsh shifts and you do have to shift manually to hold the revs.

The 500,000 mile life of the 8V92 is greatly in excess of what anybody on this forum will see so having an engine that may last the life of the chassis is so far beyond overkill it is ridiculous. Our engines will rust internally so I question the engine life in our application and long storage periods.

I think the design is elegant in an 8V92. It is too bad it was done in by emissions requirements because it was replaced by an engine that lacks the simplicity and possesses a sound so unique any one of us can tell it from any other engine on the road. You cannot get that 8V92 sound from engines that suck, squeeze, bang and blow.

I never had my DDEC computer melt so I don't see that as a problem.

[Joe Cannarozzi]

Greg 1 row.

[Petervs]

Jon,

My coach has a series 60 and a 5 speed tranny. It shifts great, it is always in the right gear, I only need to manually downshift if I am going down a long hill. It does not have any performance mode, or whatever, there is only the one mode it runs in. I think it is the same tranny you had with your 8V.

One of the things I like about my coach is that the engine, tranny, and chassis are very well suited to each other, it works really well as a unit. Marathon told me my coach was the very first 45 footer and first coach they built with a Series 60. Some vehicles have that special something when all the parts work well together. Bonanzas and IO-520s, Cessna 210s and IO-520s, and a few cars have that nice feeling about them, as does my coach.

Oh, and you don't have to tear apart the bedroom, because they do not need to be worked on. Honestly, I do not think they even have an access hatch in my bedroom.

Jon, I was not saying you had overheating problems , only that the 8V was prone to them if driven badly. I think no matter how you drive the Series 60 you are safe from overheating, as long as you watch the idiot lights on the dash if there is some kind of mechanical issue.

Lastly I must comment on your mention of the unique sound made by an 8V. Well, I agree it is a cool sound. But sheesh, that is the same argument made by the Harley guys and their potato-potato sound. The sound is not a valid reason to make an engine from an engineering standpoint. The value of an engine comes from it's efficiency and reliability. The biggest reason the 8V was phased out was the efficiency not the emissions. Detroit could not sell them to truckers when they could not compete on fuel used.

You never stated whether you would trade back......and not because you might get a $50,000 refund on the price differential of the same bus with 8V vs Series 60. I think the marketplace has voted with it's pocketbook.

I rest my case,

Respectfully submitted,
Czar of Crap!

[Jon Wehrenberg]

Hey Czar, Your comments are on the money.

Prevost should have paired the Series 60 with the five speed. I agree with your observation about it. Unfortunately the buyers were all over Prevost for the six speed, and Prevost needed the shorter overall length to get the Series 60 to fit the 40 foot bus.

I think the five speed is more robust, and while the shifts are not as smooth it let the engine revs build up more so pulling a hill was easier from the driver's point of view. Just stick your foot to the floor and things would work out.

No I will not go back to an 8V92. It puts out a lot of soot and my garage reflected the difference between the two. The oil got real dirty between changes. The 8V92 required good coolant maintenance otherwise the radiator got plugged and the engine was at risk of cylinder liner damage, more so than the Series 60.

The turbo inlet tubes were expensive and lasted about ten years on my 8V92. The steel oil pan did not last in the frozen north either and I had to replace it as well. The aluminum pan on my Series 60 shows no sign of corrosion.

The 8V92 had a lot of stuff like the power steering pump, compressor and worst of all the alternator buried on the front (actually the rear) of the engine and servicing or replacing them there was a challenge. The Series 60 has all that stuff accessible. For all those reasons I will stick with a Series 60, but they were equal in power in my mind as far as hill climbing.

[jimblu]

I just did some repairs on a pair of marine 6V92 535 HP. OEM Detroit valves, springs, cam followers, gaskets, injectors, fuel jumper tubes, and much more were readily available and as cheap as bicycle parts in Aviation, Volvo or Cat dollars. Parts will be around. Mechanics who do it, not so much. I was dragged out of never again to work in a friends confined engine room......

[dalej]

jimblu,

WE NEED TO TALK!

Seriously, You sound like you must know a thing or two about the 8V. I plan on driving mine until Jan says.... Dale that's enough, I don't trust you driving this bus anymore.

PS, I really enjoy working on my bus, anything I can do myself is a good thing.

[Joe Cannarozzi]

If you ever get any traction out of your idea Dale let me know. I would like to help to set the valves and the rack on ours too.

We have 110,000 on a factory remanufactured engine and it has not been touched the entire time.

I keep getting told the jake works fine and I can barley feel it.

[dalej]

Joe,

We'll be waiting.