Tuning BT-13

Joined
May 6, 2008
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10
I have an '88 BJ74 RHD with 13B-T. I haven't yet found out where it came from but was obviously tuned for sea level. I live at 5,000' and drive frequently as high as 10,000'.
My cruiser blows mass quantities of black smoke. This only happens with full throttle (when starting in cold weather or when accelerating) The higher I go the worse it gets. I believe it is running too rich. Does anyone out there know how I can lean it out so it will work more efrficiently/ I have cleaned the injectors but have no idea where to go from here. Are smaller injectors available? Can the fuel pump pressure be adjusted or the turbo boost turned up?
Thank you,
Rob
 
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Joined
Sep 28, 2002
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Location
Kamloops, BC Canada
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www.raddcruisers.ca
The first thing you should look at is driving style. The "gas" pedal is in direct control of the fuel delivery volume and you are in control of the "gas" pedal. The amount of pedal applied should be just enough to make the vehicle do what you want it to. DO NOT floor it in the expectation that you're going to get better response from the truck - that might work with a gas engine, but not with a diesel.

(it is assumed that you have clean fuel and air filters)

Second thing you need to look at is the amount of boost your turbo is putting out: is it enough? (at specification)

Then, if yours is high mileage, you may need to have your injector nozzles replaced. But don't do that before you have set your valve clearances back to specification. Be sure to check for pounded out rockers if they are not in spec or are noisy.

Then, check your injection timing to make sure it's within spec.

Once you have set your valves and timing, then back off the fuel screw a little. You really should use a pyrometer as a guide to how much or little to set the fuel delivery volume - install one if you have not already done so.

hth, and ymmv

~John
 
Joined
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It doesnt matter how well tuned your 13B-T is it will smoke at 10,000ft all Diesels will. It could be less air for your turbo at that altitude. Try this disconnect the Vacum line that goes to a diaphram or you can take it off the commpressor dont forget to cap it. See if this makes a bit of difference The only problem now is the engine light will go on if you are overboosting . If it stays on for more than a couple of seconds the butterfly valve will try to smother the motor of air stalling it. Could be very dangerous.
Option 2 is turning down your fuel load screw to keep it from smoking . If none of these help it is time to spend money and get new injector tips. One last thing you can try is run MOLY_PURGE to clean the gunk and s*** out of your fuel system before new injectors
 

OGBeno

www.olc4x4.com
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Hey DRROB--

You made it here! Nice.

Glad to have met you yesterday in the Sunflower parking lot and thanks for letting me spend time drooling over your rig!

Best.
-onur
 
Joined
May 6, 2008
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Onur:Thanks for your reply. It was a pleasure meeting you too!
Rob
 

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