Sorry for being a newbie - Mixture Adjustment Q's

[BreckenridgeCruiser]

So I drive my new BJ44 home from Long Beach, CA to Breckenridge, CO.

It did a great job, getting around 27-30 MPG and that was pushing it a bit. (stock driveline and 31" tires) I think I averaged 65 miles per hour.

So as I get higher in altitude (my house is at 10,500 fasl) it is easier to overfuel the engine and start smoking like a chimney. I expected this as I know that they come adjusted from NZ for around Sea Level. I am not planning on turboing the engine until next year so I just need to adjust the fuel to be better for the altitude. Here are my stupid questions:

Q1) Where is the screw that adjusts the mixture? How about to adjust the idle? (this is not the real reason I posted by the way - I know it's in the manual, but as long as I am asking dumb Q's...)

Q2) How do I know when it is adjusted properly. I was familiar with the lean idle drop method for a gas motor, but have no idea how to tell if I am leaning it out too much... How do I know when I've found the sweet spot?

Thanks again for all of your patience!

Kraig

 

[Greg_B]

Q1) Where is the screw that adjusts the mixture? How about to adjust the idle? (this is not the real reason I posted by the way - I know it's in the manual, but as long as I am asking dumb Q's...)

Q2) How do I know when it is adjusted properly. I was familiar with the lean idle drop method for a gas motor, but have no idea how to tell if I am leaning it out too much... How do I know when I've found the sweet spot?

Thanks again for all of your patience!

Kraig

1st, forget all your gasser knowledge. Things in a diesel are the other way around: it is fuel throttled, not air throttled, so you add and reduce fuel delivery to increase or decrease rpm.

Go to http://bankspower.com/tech.cfm and read all the links for a great primer on how diesels work. That would be a great starting point.

Add a pyrometer to find the correct fuel setting.

Did you get an engine manual yet?

hth's

gb

 

[brownbear]

There is a picture of what screw adjusts the fuel. But I can't remember where. Do a search under the words "fuel adjustment" in the diesel section, search this forum link.


Going to altitude will always smoke under load, the only way to avoid it would be backing off the fuel quite a bit. Then you will have no power for the rest of the time. But when you see a bunch of smoke your Exaust gas tempurature may be dangerously high(ie melt metal, cause cracks) so a very very good thing is a pyro meter. Then you drive to keep below 1250. Plus you need the gauge to do any fuel adjustments.

But you can back it down till you see no smoke. BUT you can not increase it again. Otherwise the pyro is mandatory. Only slight movements and you can be at 1600 degrees. Serious engine damage.

Search pyro on here too.