gruder
Automotive
- Aug 2, 2006
- 12
Hi All,
Recently there has been a several Isuzu 4HG1 Diesel Engines come through our workshop with overheating issues that has become somewhat confusing to rectify.
Any suggestions would be welcome.
The engines all have the same characteristic that is when under full throttle load the Temp will keep increasing to boiling point.
All minor things have been checked, as well as cooling system pressure, new radiators, water pumps etc etc but still the issues remain.
EGT is around 500C.
Also the cylinder head temp above each individual Cylinder would appear to be fairly even.
This would suggest that cooling circulation & injectors etc are all resonably even as well & not just a poor coolant flow or a bad injector increasing combustion temp in one individual cylinder.
The flow of coolant through the block & head is very good as well.
We are considering the possibillity of there being a chance that Steam pockets are forming inside the heads etc & maybe the cause of these issues. Our next step is to increase the system pressure & test this out.
If this is the case with steam pockets forming, why hasn't this been an issue since the original manufature date of the engine or has it?
Can't seem to put a single cause on this, the first one started off just as a job, by the fifth one it is more of a complex problem that has all of us scratching our heads.
Cheers
Recently there has been a several Isuzu 4HG1 Diesel Engines come through our workshop with overheating issues that has become somewhat confusing to rectify.
Any suggestions would be welcome.
The engines all have the same characteristic that is when under full throttle load the Temp will keep increasing to boiling point.
All minor things have been checked, as well as cooling system pressure, new radiators, water pumps etc etc but still the issues remain.
EGT is around 500C.
Also the cylinder head temp above each individual Cylinder would appear to be fairly even.
This would suggest that cooling circulation & injectors etc are all resonably even as well & not just a poor coolant flow or a bad injector increasing combustion temp in one individual cylinder.
The flow of coolant through the block & head is very good as well.
We are considering the possibillity of there being a chance that Steam pockets are forming inside the heads etc & maybe the cause of these issues. Our next step is to increase the system pressure & test this out.
If this is the case with steam pockets forming, why hasn't this been an issue since the original manufature date of the engine or has it?
Can't seem to put a single cause on this, the first one started off just as a job, by the fifth one it is more of a complex problem that has all of us scratching our heads.
Cheers
