Erg Cooler, Headgasket diag.

[Mekanik]

What is the best way to diag. a leaking headgasket and egr cooler. Is the best way to follow the tsb, monitoring coolant system pressure, removing the egr valve, and pressure testing the cooling system with the front end down on the ground? Does the co2 tester method seem to work well? What about an intermitent leak like only when the truck is towing? All information will be appriceated. Thanks

[snw blue by you]

The senario generally goes like this:

Blown headgasket,engine overheat,EGR cooler tube brazing melts,or cooler distorts causing the tubes to crack,engine coolant is then introduced into the EGR system,which is then circulated through the engine,and out the exhaust producing prodigious amounts of smoke from the tailpipe.

Easy check for coolant in EGR system is to remove the valve and insp both the valve and intake.

If there is coolant in the system,you'll know it,as there will be a greasy,gooy mess on the valve,and in the ports.

If it is just starting,it may still just be in the intake ports,and may not produce smoke,until the engine is good and hot.

Of course you should also see the coolant level continually dropping,after being properly filled to the correct level when cold.

If you are not using coolant,chances are thats not your problem. /forums/images/%%GRAEMLIN_URL%%/cheers.gif

 

It should also be noted that if you are using coolant,and it's not in the EGR system,you will need to look at the other parts of the cooling system in this engine.

[Mekanik]

Thanks. Do people ever just complain of a intermitent drivability? Like for instance a truck that only misfires when towing or under a heavy load?