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8V71N injector settings

Posted: Sun Aug 16, 2009 5:31 pm
by TexasBorderDude
I just had my 8V71N adjusted by Smith Power in Salt Lake City. They were very responsive, did good work and I thought their charge was reasonable. They found a short on a jake solenoid, found another that was bad, and lots of crispy "O" rings on the solenoids. They adjusted the jakes, ran the rack and set the injectors. Here's the rub.... lots of black smoke in any gear at any speed; it runs 8-10 degrees hotter and burns about 20% more fuel. The injectors are 70's. Anyone know the correct gap (if that's the right term??)

Edit.... I think it the height setting, no????....

I'm going to call them tomorrow (Aug 17th) and would like to know what's recommended. I'm confident they are set too rich, but what's the preferred setting?

Thanks,

dg


ps. One of the board's finest already told me that there are different settings for truck vs. bus applications for the 8V71. Thanks!

Re: 8V71N injector settings

Posted: Sun Aug 16, 2009 6:00 pm
by Dreamscape
And what would that be?

Re: 8V71N injector settings

Posted: Sun Aug 16, 2009 6:10 pm
by TexasBorderDude
Dreamscape wrote:And what would that be?
TexasBorderDude wrote:rich, but what's the preferred setting?

I asked first!!!! hehehe!

Re: 8V71N injector settings

Posted: Sun Aug 16, 2009 7:23 pm
by Dreamscape
TexasBorderDude wrote: dg
ps. One of the board's finest already told me that there are different settings for truck vs. bus applications for the 8V71. Thanks!
The above quote is why I asked, your turn! ;)

Re: 8V71N injector settings

Posted: Sun Aug 16, 2009 8:25 pm
by luvrbus
If DG knew what injectors he has it would be easy but the guy at Smith told him he had 70's and I doubt if he does .
I am thinking he has 60's his engine burned to clean to have large injectors and A timing.


good luck

Clifford

Re: 8V71N injector settings

Posted: Mon Aug 17, 2009 7:48 am
by TexasBorderDude
Good point, Clifford! When I talk to Smith, I'll question the injector size too. Thanks.

Re: 8V71N injector settings

Posted: Thu Aug 20, 2009 11:19 am
by TexasBorderDude
Smith's made good on the adjustment... I've got 70's and they adjusted them at .1460 I headed out of Boise and had more black smoke than ever! My heart sank.... I stopped at a rest stop and blew out the air filter... it was filthy! Much improved, but still lots of black smoke anytime under load. Again about 5mpg. When Smith in Salt Lake did the tune-up they said my air throttle was not allowing full throttle, so on this tank of fuel, I'm really using the lightest throttle possible and at the first hint of black smoke I back off. Top speed is about 54 on the flat at 1500 rpm in 4th. We'll see. I was actually getting 6.5 plus mpg with my old setup (detuned and a restricted throttle). Oh she's running great and has more power that ever..... duh! :D

On to Yellowstone.

Thanks for all the help.

dg

Re: 8V71N injector settings

Posted: Thu Aug 20, 2009 11:52 am
by Dreamscape
Doyle,

On our 8v71n I get black smoke only when I have my foot mashed to the floor. Slight smoke on the flats when I pass someone, which is rarely, and a lot more when climbing a hill. I always watch my mirrors for the black smoke and back off slightly. I can still run at 70/75 if I want and not see it.

I do not kow what injectors I have, never have taken the time to find out. I know our beast with the four speed manual is a slug at times, but I'm going to live with it.

I'm just surprised after all the work you had done that your mpg went down, a lot too. I think I'll leave mine alone! ;)

Are you still pulling your trailer?

Re: 8V71N injector settings

Posted: Thu Aug 20, 2009 1:45 pm
by luvrbus
Well when you are 75 long and weigh 50,000lbs running in the mountains with your engine turned up to 2500 rpm and checking the new 3:36 rear gear in 3rd gear plus letting Coffee drive thats what you get huh Doyle.
But we will put a stop to that smoking this winter when we turbo that 8v71

Clifford

Re: 8V71N injector settings

Posted: Thu Aug 20, 2009 3:21 pm
by TexasBorderDude
luvrbus wrote:Well when you are 75 long and weigh 50,000lbs running in the mountains with your engine turned up to 2500 rpm and checking the new 3:36 rear gear in 3rd gear plus letting Coffee drive thats what you get huh Doyle.
But we will put a stop to that smoking this winter when we turbo that 8v71

Clifford

Yep, Ciff you are right! No more driving for Coffee... she's such a lead foot!

Found Henry's Lake an Idaho state park and am set up for 4 nights. Will take Coffee and the car and tent camp at Yellowstone... only 45 miles to West Yellowstone.

dg

dg