Black smoke.......sometimes
Submitted: Thursday, Mar 16, 2006 at 17:48
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Cruising
Hi all, hoping someone can help me with this problem. My 93 poverty pack 80 series wagon gets around 14-16ltrs/100k. This figure goes out to around 17-18ltrs /100kwhen towing my 23ft caravan. The problem is that on long pulls up hills (in 3rd or 2nd gear) I get to about 1/2 way without any excessive black smoke out the rear then suddenly, without any more throttle, black smoke just pours out the exhaust. lifting off on the throttle only results in losing speed and smoke continues to pour
forth. The injector pump has recently been overhauled and so have the injectors (supposedly...). 309000ks on the clock and no visable oil useage on the dipstick between oil changes at 5000k with filter changed as
well.
Thanks to all
Rob H (qld)
Reply By: Footloose - Thursday, Mar 16, 2006 at 18:02
Thursday, Mar 16, 2006 at 18:02
AFAIK, These engines accumulate soot, especially in the exhaust system. Giving it a good load can result in a goodly amount of black exhaust for a while. The trick, I guess, would be to do the same
hill twice and see if the amount had decreased dramatically. I'm betting it would.
I had
mine repaired because of hail, it took 7 weeks. When I picked it up it belched black smoke for about 20K (luckily nobody reported me !). Next day it was fine and has continued to be so.
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Reply By: Member - Duncs - Thursday, Mar 16, 2006 at 20:08
Thursday, Mar 16, 2006 at 20:08
You say it is a poverty pack, does that mean no turbo?
If you are climbing and at altitude say going over the Blue Mountains a normally aspirated diesel will blow smoke as the atmospheric pressure drops. This is because in the lower pressure the fuel mix becomes rich. It is not as big a problem witha turbo because the combustion chamber is presurised by the turbo and the fuel mix doesn't vary as much.
I first noticed the same problem in my old MQ SD33 no turbo. I had a major panick looking in the mirror while climbing through the
Snowy Mountains.
If this is the problem getting the fuel pump serviced at a workshop that is a bit above sea level will help.
Duncs
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Reply By: Peter 2 - Thursday, Mar 16, 2006 at 22:42
Thursday, Mar 16, 2006 at 22:42
I put my troopy (same donk) on a dyno a few years back just for interest sake, it blew heaps of smoke when loaded up as if climbing steep hills in lower gears, the dyno bloke reckoned it was pretty normal for a 1HZ as most did it when pushed hard.
It did run cleaner after a long trip, probably shifted all the crap out.
since I've been running the biodiesel in the Humvee for acouple of months now it doesn't blow any smoke and the exhaust is longer sooty black either.
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