layback40 wrote:
GordnadoCRD wrote:
If that were mine, I'd try using needle-nose vice grips on the timing plug and leave the EGR in place, if I had no plans to remove it entirely.
GordnadoCRD
Please read the description of the EGR in the post back a couple.
It explains that the introduction of exhaust gas reduces peak combustion temperature.
This is why I have previously said that making the mixture richer lowers EGT. There are 2 ways of richening a mix, 1/ add more fuel. 2/ add less oxygen. When you add exhaust gas you reduce the amount of oxygen present in the charge gas. This richens the mix as you have less oxygen for the given amount of fuel. By lowering the flame temperature, you lower the EGT. I have seen this on other diesels, typically lowers by 100 F. With an EGR delete this no longer happens & there will be higher EGT's & so hotter exhaust valves. & you know what happens then!
Sorry to hijack thread.
Rich mix on a diesel is HOTTER EGT not colder. It is exactly the opposite from a gas engine. Running a diesel hot and working hard, if you reduce the amount of oxygen in the cylinder it melts pistons. It does NOT COOL THE ENGINE.
Diesels are a lean-burn engine. At idle they can be as much as 250:1 air/fuel. But the EPA thinks that lean burning makes too much (or any) NOX, so they want everything to be running RICH to try and counter this. On a gasoline engine this does cool off the cylinders, and a gas engine running lean will melt pistons. So rich mix protects the GASOLINE engine but damages a diesel engine.
To cool off a diesel, ADD MORE AIR or reduce fuel. Usually the answer is a combination of both, making the mix more lean.