6.4 air bubbles in bleed line...

[STROKER_T]

Mornin DTS peeps...was wondering if it's ok to smoke the fuel system on a 6.4 to trace a leak...

 

 

'08 f250 comes in,no crank...engine is locked tighter than a well diggers ass,pulled glow plugs,nothin...pulled oil pan,found chunks from the bottom of a piston,turns out #2 had catastrophic damage at piston pin area,pin and what was left of piston was lodged in cylinder wall...no burnt pistons,but piston orientation suggested crank twist/bind....this truck has only 28k on it,frigging ridiculous....

 

So I put a short block in the piece,very careful on fuel line replacement and torque procedure,but nevertheless there are bubbles in the time saving bleed tool hose,recycled 7 or 8 gallons while it idled,engine purrs,no issues yet...'cept for the bubbles...

Thanks for reading this,just wondering the quickest,least intrusive way to find the bubble cause...what a p.o.s engine...

Smoke shouldn't hurt the system,right...

[Aaron]

how big are the bubbles? I have been told by a hotline engineer that champagne-sized bubbles can be considered normal, maybe compare to a like unit?

 

You don't have fuel running out onto the ground, right?

[STROKER_T]

The bubbles on this one are not tiny by any means,no leaks....low fuel pressure is 9 1/2 - 10psi at KOEO,and 4psi while running...

No evidence of fuel in the oil,and hindsight tells me smoke won't work unless ALL fuel is out of system,woulda coulda shoulda smoked it at the heads before installing valve covers...maybe a hi-pressure problem...? Not sure yet,still testing....gonna run hi pressure test,any ideas or similiar concerns...?

[rlchv70]

It's likely coming from the injectors. You could narrow down one bank by disconnecting and plugging each cylinder head. Otherwise, no other suggestions.

 

Just checking: You remembered to put new combustion gaskets on the injectors, right?