99.5 powerstroke upper end knocking

[cruiserhed]

Hi all,
I've got a knock, or loud tick coming from I think the top of the engine. I increases and decreases with rpms. Sounds just like a collapsed lifter but I've got the valve covers off, have rolled the motor over manually, the valvetrain seems tight. No loss of power, not even a miss. I popped each injector harness off one at a time while it was running and noticed a drop in rpm each time, so Im assuming they're working. glow plugs are all there and in good shape, I read that one could've broken off into the cylinder but that's not the case.

any suggestions? could an injector be bad or causing a knock and still be functioning?
Im in the garage right now so any ideas are appreciated.
thanks

99.5 7.3L, 160k miles, oil changed regularly, no other symptoms.

 

[Frankenstien]

Things that make you go hmmmmmmm

have you made any progress yet?

 

[roosterdiesel]

How full is the fuel tank? May have air in the fuel problems.

 

[cruiserhed]

nothing yet!

No good progress yet, tank is about 2/3 full. I haven't let it get down below about 1/4 of a tank in a while either.

thanks for the replies.

I'll keep trying.

 

[CHPMustang]

How long ago did these symptoms start there cruiser?

 

[dzl_x_4x4]

Did you or anyone work on your truck lately. Is it a tick or a KNOCK? Did it happen after a fill-up,? while driving? or just happened over night?

 

[cruiserhed]

latest

It started the other day on the way home, seemed to start like a very light ticking and progressed to more of a knock. It got to a point and peaked and it is the same now all the time. It was between fill ups, nothing had been done to it recently. I put some power service in it since then and drove it to and from work just to maybe get lucky but it hasn't gone away. I just bought a few good used injectors and my next plan is to switch them out one a time and see what happens, it's parked now, I don't want to keep driving it like this.

thanks for the replies.

keep em coming and I'll keep you posted how the injectors work.

 

[dzl_x_4x4]

Does it smoke (white,blue,etc.) on startup or running?

FWIW: I would look for fuel leak or an oil leak, I am certain that both could cause these symptoms. If you get air into either system you can get a heavy knock. Mine sounded like someone was beating on it with a hammer before I did the oil high pressure cross-over mod. (mine is a 7.3). If you did that look to see if any connectors or oil plugs are leaking. If not, I would do it when was replacing the injectors (hour job, $50) it made mine very quite.

 

[cruiserhed]

hmm interesting

thanks, I might have to try that kit. I swapped out injectors today one at a time and not a thing changed, still knockin away.

I think I've isolated it to pass. side front, but that is as close as I can narrow the knocking. Definitely upper end.


I haven't noticed any unusual smoking at startup, but I'll take a closer look for leaks. Where did you buy crossover mod, I might have to try it.

thank you

 

[CHPMustang]

Where did you buy crossover mod, I might have to try it.

Dennis at ITP carries the new SS crossover kit