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93punow
04-06-2009, 20:45
93 chevy 6.5 turbo diesel
driving it and then started to her wat sounded like to be a knock.
checked rockers,injectors,pushrods. Not knowing wat else i could check.
had injectors checked 2 poor 6 fair wonder if this could be the problem. only happens the most with gaining of rpm's. sounds to be top end

Thanks

6.5 Detroit Diesel
04-06-2009, 20:55
Blocked pushrod? Did you pull them all and check them? Unless you are sure oil is getting through them all, that could be your cause.

93punow
04-06-2009, 20:58
how would you go about that of checking for the blockage

6.5 Detroit Diesel
04-06-2009, 21:01
Well
The only way that I know of to really check them, is to remove them from the engine. Which means, removal of valve covers. Blow them out and ensure they are clean. Could be some crap in the engine.

93punow
04-06-2009, 21:04
thanks yeah its nothing to pull them almost top tore of turbo intake valve covers, injectors if you can think of anthing else. i am this far now thanks for your help

DmaxMaverick
04-06-2009, 21:55
93 chevy 6.5 turbo diesel
driving it and then started to her wat sounded like to be a knock.
checked rockers,injectors,pushrods. Not knowing wat else i could check.
had injectors checked 2 poor 6 fair wonder if this could be the problem. only happens the most with gaining of rpm's. sounds to be top end

Thanks

The usual suspect. In a Diesel engine, a misfiring injector can sound like a rod about to come through the block (the same sound on a gasser can make you run for cover). Most noisy during acceleration and under load (higher RPM's).

Lifter knock will most likely be at lower to mid RPM's (less oil pressure), and lessen at higher RPM's.

A blocked pushrod won't make any noise. But, the rocker may launch through the valve cover (or at least parts of it), after being starved of lubrication. A lot of noise before (just before), then bam! A very unlikely candidate, as oil gets splashed around under the valve cover, and they don't require much at all. A bent pushrod, on the other hand.....

A good second guess would be a sheared/worn rocker button (centers the rocker on the shaft). They are nylon, and tend to fall off on their own, without any help, once in a while.

6.5 Detroit Diesel
04-06-2009, 22:11
lol, in my rather few experiences, blocked pushrods starve rocker and make noise the more they are pushed. But, when I did drop a pushrod, it made similar noises to what he said. :eek: