final decision on motor knock!

[typhooey]

WELL IVE HAD JUNIOR1 COME OVER WITH HIS DATAMASTER AND WE DID A CHECK ON THE TRUCK IT SEEMED EVERYTHING WAS GOOD EXCEPT FOR HIGH KNOCK,SO AFTER THIS POINT THE NEXT STEP IS TO CHECK THE TIMING AND MAKE SURE ITS AT ZERO WHICH I DID TONIGHT,AND IT WAS AT 1 DEGREE WHICH I DONT THINK AND CHRIS BELEIVES THAT IT IS MOST DEFINETLY FUBAR!!!!!! SO NOW IM CALLING OUT FOR ALL THE HELP I CAN GET WITH ADVISE ON WHICH COMBINATIONS TO DO TO BUILD A NICE MOTOR.

 

[MikeRenz]

how much knock were you seeing? I wouldn't just assume its shot from a little knock.

 

[typhooey]

I DONT KNOW WHAT ELSE TO DO?THE KNOCK GET LOUDER AT HIGHER REVS

 

[SYO237]

MOVING TO THE ENGINE TECH AREA!

 

[Sy769]

I ASSUME YOU ARE REFERRING TO DETONATION RESULTING IN TIMING BEING RETARDED RIGHT?

I'VE TUNED ENGINES THAT STARTED OUT WITH AUDIBLE KNOCK THAT EVENTUALLY WAS RESOLVED. IT DEFINITELY CAN KILL A ENGINE BUT KNOCK RETARD ALONE DOESN'T MEAN THAT THE ENGINE IS GONE.

DO A SEARCH AND YOU WILL FIND SEVERAL NO WAIT MANY MANY THREADS DEALING WITH MAKING THESE TRUCKS RUN WITH NO SPARK RETARD.

SOMETHING AS SIMPLE AS A TUNE UP HAVE CURED MANY TRUCKS WHILE SOME NEED MORE WORK

NOW IF YOU ARE REFERRING TO MECHANICAL KNOCK IE CONNECTING ROD PUSHROD ETC. TOTALLY DIFFERENT SCENARIO.


Btw most people would rather you didn't type with the caps lock on :tup:

 

[Junior1]

It sounded like mechanical knock to me. It was audible at idle and got progressively worse. I put it on datamaster and it was pullin spark as soon as it was given gas and the knock count went through the roof.
Keep in mind it was put on DM after the plugs, wires, cap, etc were changed out. He said the timing was only off 1 degree. I did not want to do a full throttle blast with all that knock either.

 

[Sy769]

Okey dokey mechanical knock.

Here's what I'd do

Remove the belt. start the engine. Still hear noise?

Run a compression test

Remove the valve covers valvetrain intact?

Remove the TC cover. Any sign of loose TC bolts or flexplate bolts?

You can also remove the plug wires one at a time with the engine running. If it is a rod knock you "should"hear a difference

 

[Captain Morgan]

 

[dgoodhue]

NOW IF YOU ARE REFERRING TO MECHANICAL KNOCK IE CONNECTING ROD PUSHROD ETC. TOTALLY DIFFERENT SCENARIO.

FYI I ran a scan tool on a truck with a rod knock (audible as you gave it gas) and my scan tool didn't pick it up.

 

[Junior1]

The compression test was already done, 2 cylinders came back bad, although I don't know how trustworthy the source was because Mark took it to a Chevy dealer and said it didn't look like they touched anything under the hood of the truck.
Next steps would be to pull the valve covers and pull each wire one by one to isolate it.
Just seems strange a used car dealer would send 3k back so fast if something wasn't already wrong with it...

 

[typhooey]

I dought the dealer even did a compression check due to the fact that when I did the tune up there was no evidence that the plugs or wires were even touched so therefore I dont trust that at all. im still having a little faith that the motor might still be good just has some bugs but as ive found out these trucks suck!!!!!! to work on I mean what a bitch!!!I would like to find a trustworthy turbo mechanic that I can actually watch work on the truck.