Overheating / preventative solutions
Posted: Fri Aug 08, 2008 12:14 pm
- thermostat replacement
- recore/flush radiator & coolant system
- oil change
- Injection pump/timing set/adjustment
- pyrometer gauge * I cannot stress this one enough*
Needless to say, I have done all of the above and can still go past 1500 F on my exhaust temps going up hills if I really push it (causing serious heat buildup in the head/engine).
If you have a good working coolant system, most 4D56's will go like a workhorse without topping the temps, however you can still do long-term damage (heat scores/cracking) internally without knowing it climbing hills at high RPM without monitoring the exhaust temperature.
The coolant temp gauge that sits in the dash does not read exhaust temps.
- recore/flush radiator & coolant system
- oil change
- Injection pump/timing set/adjustment
- pyrometer gauge * I cannot stress this one enough*
Needless to say, I have done all of the above and can still go past 1500 F on my exhaust temps going up hills if I really push it (causing serious heat buildup in the head/engine).
If you have a good working coolant system, most 4D56's will go like a workhorse without topping the temps, however you can still do long-term damage (heat scores/cracking) internally without knowing it climbing hills at high RPM without monitoring the exhaust temperature.
The coolant temp gauge that sits in the dash does not read exhaust temps.
jfarsang wrote:Pyrometer gauges are common on heavy diesel rigs.
You can push the Delica pretty hard but there is a point where the temps will be too high, hence the gauge.
crushers wrote:a pyro should be on every diesel engine, not cheap but then neither is a cracked head...
Erebus wrote:I've got a pyro (EGT or exhaust gas temperature) guage in mine. Installed after the turbo (makes a difference in the readings). Anyway, normal cruise is in the 800-1000 degree F, climbing a steep hill like the Coke, or the Dempster, it can climb to 1300 with no effort, and the worst stretches it reaches 1500 while you are in 2nd or 3rd gear doing 70 or 80 km/h. When it gets to those levels, the coolant temperature will rise too, from my normal of just above 1/3 to just above 1/2.bobenns wrote:I'd be interested to hear more about exhaust temp with these vehicles though. One would almost expect there to be a factory installed temp sensor in the exhaust if this was an issue.
When you come over the top of the hill and start down with almost no throttle, the EGT drops really quickly (as in seconds), the coolant takes a little longer.
On a long downhill, the EGT will drop to about 300.
One of the nastiest things to do to a turbo is turn the engine off while it is spinning high, or while really hot. Exactly what happens when you pull off the highway at a fuel stop.
I've made it my policy to not shut off the engine until the EGT drops below 500. At home this isn't usually an issue; the several blocks of suburban streets from the highway are enough to drop the temp down. But where I'm staying right now (Whitehorse) is at the top of long hills, so it takes several minutes of idle to drop down.
When highway driving and stopping to refuel, if the diesel pumps are separate from the gas pumps, don't shut the engine off. The warning signs about "shut off the ignition" only applies to gas engines (after all, diesels don't have ignition systems), so as long as you have separation you should be fine. Not that employees would know this.
Having seen what information a pyrometer gives me, I don't think I'd want another vehicle, especially turbo, without one.
Just my 4 cents worth.