im looking at buying a 89 bighorn. it all looks good but there is one thing that concerns me. there seams to be a bit of oil coming out the breather.
the owner says that it only hapens on long journys and not round town. has any one heard of this problem before and anyone know the solution.
any ideas would be great.
cheers.
That is a common fault on the isuzu deisels, run a hose from the breather into a catch can, then another hose back to the intake. On the bottom of the catch can run a small hose down and join it into the side of the dipstick tube so the oil runs back into the sump.
Andy at Amma motors in Christchurch makes these up out of alloy to suit he sell a kit which bolts on and solves the problem Ph 3660 454.
If there is any blowby at all on a forced induction motor then the crankcase gets pressurised.
A lot of NA cars that get blown suffer from this, the amount of blowby can be minimal but still cause oil to come out.
The catchcan mod will work well. If you are looking at buying the vehicle then you should get it checked out by someone before buying to make sure there aren't any problems.
During normal operation, a small amount of unburned fuel and exhaust gases escape around the piston rings and enter the crankcase, referred to as "blow-by". [6] If these gases remained in the crankcase and condensed, the oil would become more diluted over time, decreasing its ability to lubricate. Condensed water would also cause parts of the engine to rust. [7] To counter this, a crankcase ventilation system exists to draw fresh air in from the air filter and expel the gases out the PCV valve into the intake manifold. The intake manifold is at a lower pressure than the crankcase, providing the suction to keep the ventilation system going.
If an engine is damaged or enters old age, gaps can form between the cylinder walls and pistons, resulting in larger amounts of blow-by than the crankcase ventilation system can handle. The gaps cause power loss, and ultimately mean that the engine needs to be rebuilt or replaced. [6] Symptoms of excessive blow-by include oil being pushed up into the air filter, out the dipstick[8], or out the PCV valve.
fish wrote:im looking at buying a 89 bighorn. it all looks good but there is one thing that concerns me. there seams to be a bit of oil coming out the breather. the owner says that it only hapens on long journys and not round town. has any one heard of this problem before and anyone know the solution. any ideas would be great. cheers.
I had a Mu with a 2.8turbo and she did the same thing it will only get worse trust me i wouldn't touch it unless you want to do the engine. Mine used to fill a 2ltr coke bottle in 3 days on a long trip and it only got worse! ended up replacing the engine