Author Topic: Tech Tip: Preparation For Running Out Of Fuel...  (Read 8240 times)

Offline John E. Smith

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Re: Tech Tip: Preparation For Running Out Of Fuel...
« Reply #30 on: October 23, 2006, 10:57:07 PM »
Got a new plan....going to install dry and the primer and fill the primary, tighten the primary, and run the pump until fuel runs out of the loose secondary and tighten it down.  How's this sound?  It sure as he11 won't be any nastier than trying to install full filters on an MC9...that's a poor location for fuel filters.     
I'm open to any ideas on this subject that may improve changing fuel filters.   Perhaps this time won't be so bad. 

Bad idea...

If you can back your bus over some sort of drop-off, changing filters is much easier... they were designed to be done in a pit.

Another little modification that makes changing filters easier is the installation of a shut off valve on each side of the filter head -- simply shut off the valves, remove old filter, prime & install new filter, open valves.  One tip... when you start the engine after changing filters, rev the engine to about 1800 rpm or so and hold it there.  That higher rpm (and higher fuel pressure) will allow the engine to make it over a small loss of prime when it hits an air bubble.  And having a valve on each side of the filter head makes sure that any air bubble will be a small one.

This modification has been standard on most -- if not all -- class 8 trucks with the DD engines for quite some time now.  All of my Internationals had it, and most of the Freightliners I drove for other people had it too.  Don't know why bus manufacturers never thought of it!
John E. Smith

Offline Busted

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Re: Tech Tip: Preparation For Running Out Of Fuel...
« Reply #31 on: October 24, 2006, 10:19:41 AM »
Don't let Dallas fly IFR!!!

Offline buswarrior

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  • '75 MC8 8V71 HT740
Re: Tech Tip: Preparation For Running Out Of Fuel...
« Reply #32 on: October 24, 2006, 11:47:58 AM »

Out on the road, fuel consumption is primarily a wind thing, not a weight thing.

Pushing the air is what takes the big power.

That is why fuel economy degrades so badly with an increase in speed.

In the apples versus oranges world,

4 strokes main claim to fuel economy fame is that they can make enough power in the engine's sweet spot to pull an overdrive gear at highway speed. The 2 strokes usually can't.

Horsepower is another word for fuel consumption. The 4104 get the fuel economy they do because they are small in frontal area, and they have little to no excess horsepower.

A roof raised, wide body coach with 450 HP..... will consume fuel.

Gearing is another minor key, and always a compromise,  to squeeze what you need from what you've got for where you go.

For fuel economy, smallest motor that will make it go, geared for your terrain, smallest frontal area, shed the awning and roof airs, install some air tabs on the rear sides....

For the truckers.... An old industry guru by the name Stan Kimberly used to write for the trade mags.... To move 80 000 lbs of 18 wheeler down the highway, anything bigger than about 280 HP was a waste of fuel. Just physics, so much to move the weight, so much to push the wind and a little more for a bit of gradeability when the road rises in front of you.

Wow, wonder what his HP calculation would have been for a 35 000 lb MCI?

happy coaching!
Frozen North, Greater Toronto Area