Where is everyone #5

You're correct, soot is a result of incomplete combustion.

If the engine got hot enough to achieve 100% combustion, it would probably melt down, probably not the block, but everything else would be destroyed.

No matter how hard you press that pedal, you will not achieve 100% combustion. You will however, be able to push a lot of fuel through that engine, some of which won't even make any power. Since there is at least some incomplete combustion, pushing more fuel will lead to more soot. In order to get the engine hotter, you have to burn more fuel, at a faster rate, which leads to more soot.

How hot does diesel need to get to achieve 100% complete combustion? I don't know, but I bet it's hotter than 240°, which is the hottest mine has ever been, and that was pushing it hard.

 

Same thing as a Volvo motor as far as I know.

 

While water temp definitely plays a part in it, it’s less as important as compression ratio and piston design. I don’t know what the combustion efficiency is with these newer engines other than much higher than their predecessors. I don’t even think that if 100% combustion is achieved that it would totally eliminate soot.

 

Is that good or bad?

 

From what I’ve read here and elsewhere it’s good.

 

Don't they just run them leaner now to get the temp up. Just like they have being doing in the eco gas cars for awhile now?

Edit: Holy shiat, 240°? I get freaked out when mine goes much over 200. I turn the fan on manual when it hits 195.....which isn't often.

 

I ran mostly Volvos for the last 7 years before my heart attack, I thought that they pulled as good as our Freightliners hauling super-b's and some even better. They had a lot less trouble with emissions equipment than the F'liners and Cummins powered units that were leased on to the company. They had a bad batch of Injectors in 2013/14 that were a problem for about a year until warranty got them all changed. Since then the D13 was an almost bulletproof engine and the Volvos rode like a dream compared with the F'liners on the fleet.

 

The Volvo d13 and Mack mp8 are the same engine?

 

Different paint and possibly programing but I am told they are out of the same engine foundry.

 

My engine runs 210° normally, coolant temp around 175°. The fan automatically kicks on at 225°, but I usually manually turn it on at 200° on a long grade and drop a half step.