Chrysler RAM TRUCK 2500 1994 Service Manual page 736

1
•
ENGINES 9 - 1 5
S E R V I C E DIAGNOSIS (DIESEL ENGINE) - MECHANICAL (CONT.)
C O N D I T I O N POSSIBLE CAUSES CORRECTION
LUBRICATING OIL
PRESSURE T O O HIGH
Pressure s w i t c h / g a u g e not
o p e r a t i n g p r o p e r l y .
Verify the pressure switch is functioning correctly. If not,
replace s w i t c h / g a u g e .
Engine r u n n i n g t o o cold. Refer t o Coolant T e m p e r a t u r e Below N o r m a l (Engine Diagnosis—
Performance)
O i l viscosity too thick. M a k e sure the correct oil is b e i n g used. Refer t o G r o u p O ,
Lubrication a n d M a i n t e n a n c e .
O i l pressure r e g u l a t o r valve
stuck closed or binding.
Check a n d replace valve, a n d / o r oil cooler cover.
LUBRICATING OIL LOSS External leaks. Visually inspect for o i l leaks. Repair as r e q u i r e d .
Crankcase being overfilled. Verify t h a t t h e correct dipstick is b e i n g used.
Incorrect oil specification or
viscosity.
(a) M a k e s u r e t h e correct o i l is b e i n g used.
(b) Look for reduced viscosity f r o m dilution w i t h f u e l .
(c) R e v i e w / r e d u c e t h e o i l change intervals.
O i l cooler leak.
Check a n d replace t h e oil cooler.
High b l o w - b y forcing o i l o u t
the breather.
Check t h e b r e a t h e r t u b e a r e a for signs of o i l loss. Perform t h e
r e q u i r e d repairs.
Turbocharger l e a k i n g oil to t h e
a i r i n t a k e .
Inspect t h e a i r ducts for evidence of o i l transfer.
Repair as r e q u i r e d .
Worn valve seals. Inspect a n d replace t h e v a l v e seals.
Piston rings not sealing (oil
b e i n g consumed b y the engine).
Perform b l o w - b y check. Repair as r e q u i r e d .
COMPRESSION
KNOCKS
Air in the fuel system.
Poor q u a l i t y fuel.
Bleed t h e fuel s y s t e m (refer t o G r o u p 14, Fuel System).
Verify b y o p e r a t i n g f r o m a t e m p o r a r y tank w i t h g o o d fuel. Clean
a n d flush t h e fuel supply tanks. Replace f u e l / w a t e r s e p a r a t o r
filter.
Engine o v e r l o a d e d . Verify that e n g i n e l o a d r a t i n g is not b e i n g e x c e e d e d .
Incorrect injection p u m p t i m i n g . Check a n d t i m e injection p u m p (refer to G r o u p 14, Fuel System).
I m p r o p e r l y o p e r a t i n g injectors. Check a n d r e p l a c e i n o p e r a t i v e injectors.
J9109-266