Hey guys I have a bad engine knock at only 54k. We have installed new injectors (75 HP Edge) and Glacier pump, they both were bad but still have a nasty knock. Cold started sound the worst and when warmed up it is still there just quieter. Also after 1000 miles on a oil change the oil is still REALLY REALLY clean????

What else to look into? Thanks in advance.

 

Describe a " bad" engine knock.

Here's mine

2001 24v. Knocking, up high, #6 cylinder. if you used a stethoscope, you can hear it pounding right at the top of the block, where it joins the head.

Send out an oil sample, comes back perfectly clean
Check compression, all cylinders are bang on
Pull drain plug, let engine drain, borescope bottom end while rotating assembly, no excess play.
Drop dial indicator into all cylinders, no measurable slop in wrist pins.
Cooling nozzles all working fine
Check valve set, all is good. While at it, check spring height, all is good. No valve problems.
Change injectors between cylinders, no change noted.
Sound getting worse at this point.
Pull head, check all cylinders, valves, protrusions, look for signs of physical contact. Nothing found
Reinstall head, torque to spec.
Also checked idler, tensioner, all pulleys, alternator, belt, AC pump. No problems noted.
Ran engine with no belt. Knock still there. Same place.

Completely reassembled engine and ran it. Had enough goofing around, when it pukes, I'll know where the knock is, til then.... so it goes.

If it is in the rear of the engine, it could be the clutch or the front of the tranny throwing noise up through the reciprocating assembly. I borescoped the clutch area, and noticed nothing wrong, I sent a trans oil sample out, and it came back clean, so I am not seeing anything flying apart in there either.

The mystery knock, and my complete indifference to it continues. This is now 20,000km and four oil changes down the road.

Any Guesses????

Good luck, be sure and let me know what you find

 

I have the same issue with my 99, except I haven't investigated the noise at all. I haven't lost power and my mileage is the same, that sound sure is annoying as hell. ohhh well till she blows

 

Thanks guys.


It is a 6spd so I never really thought about the trans/clutch making any noise. I am going to swing it by the dealer to have a friends friend look at it also. It has no loss of power nor mileage. Matter of fact it is getting great mileage and with those new injectors it really moves. Its kind of weird to me that the oil is REALLY clean even after 1000 plus miles on this change.

I will post up my outcome. Thanks

 

I wouldnt sweat the clean oil. At 5000 miles I can see through my oil. That just means you dont have blowby issues. Run it, When it breaks youll know what it was.

 

I agree with everyone on driving till it blows. I've had a slight ticking noise and a slight knock for a long time. The truck runs like a cheetah on crack so i have no complaints(can't hear it at WOT). Still getting 16 mpg on Edge level 5 driving it like I stole it. Just start throwing some money away in savings for when it does go BOOM.

 

I have had a tick near back top drivers side and can't find it, adjusted valves still their, sounds like an exhaust leak right by my right foot, who knows. I gave up trying to find it. Like everybody said drive it, if it has good oil pressure.

 

Speakin of blowby i recently read a procedure on here that explained how to measure how much blowby your gettin but there was no specs on what is acceptable anybody got a clue to what them specs is

 

Dealership said #5 and #6 wrist pins?? DOA???

 

Hard to believe its rist pins with 54,000 miles. It sounds like you have fuel knock. To much fuel in one cylinder. It would be worse when cold since there's not enough heat in the cylinder to fully burn the fuel.

MY vp44 has almost 187000 on it now and I sure its out of calibration to some degree. I have never had a knock untill this morning with the temp at 26degrees. I'm in Portsmouth VA doing a job. Live in Florida. So I feel one cylinder is getting more fuel than the rest and thats what I'm hearing, I hope.

I've heard this sound alot with 2cyc diesels in past with bad injectors.

Gonna keep an eye on it.

Dave

 

I doubt wrist pins as well they are massive about 2" lots of surface area.

I had a knock in my engine and it ended up #3 cyl wall

The thrust bearings on these engines are 1 half and may be suspect

 

VP44s are not exactly quiet...especially when the truck is cold.

 

This part is very true, my heater grid just went out and the knock seems worse in the morning. When the motor warms up the knocking seems to go away.
I also have a feeling my converter bolts are loose, when I back off the pedal while in OD, I feel a slight shudder while coasting. It feels like the converter wants to come off.

 

Dave,
This is what I have been thinking all along. But with a Snap on scanner we turned a the injectors off one at a time and it is still there.
Also when it warms up it is not even there.(well I can hear it just because I am used to the cold starts) Also I would think that if it were wrist pins it would get loader when I hiold the accel pedal at about 2800rpm. It seems to go away with a few rpms.

I wonder what there is next to do???

 

What an exasperating thing to have.

The Snap-on scanner can turn off cylinders individually? Wow, would THAT be a cool tool to have!

Have you confirmed that it's the #6 cylinder?

jh