New injectors and still awful knocking???

[trackspeeder]

All it takes is one weaker injector to cause that flywheel to have to put out extra work to dampen the vibrations, then that extra work begins to bang on the stops, then it gives out.
I wouldnt doubt that they wear out after 250k or whatever, but not at 100k for no reason.

Heavy towing and throwing some good HP at a DMF will toast it pretty quick.

 

[Classicfordguy]

My dual mass flywheel actualy has around 200k on it. My 5 speed came out of an 89 regular cab I think. I did have a piece of a spring break off one day (about half a curl) and make an awful scraping noise till I pulled it out with pliars.

I'll take it out for a drive and take note of what happens when it begins to boost.

-Rob

 

[Classicfordguy]

The boost is rock steady when I get on the throttle, no pulsing or vibration. For a few tries the Knock seemed to go away when the boost went up but for several other tries I could still hear it. The knock is the loudest at low speeds under very mild acceleration and at idle. It comes and goes and changes pitch so frequently while driving that its realy hard to pin down.

-Rob

 

[Classicfordguy]

So what does it mean if the boost is steady or jumpy?

-Rob

 

[6 Nebraska IDIs]

Well, jumpy could mean bad turbo. I dont know what else the other guys are getting at with it.
Your knock sounds allot like one we have going on with my moms 94 factory turbo truck. It has a distinct miss, and a slight knock, and its going to kill our new DMF if we dont fix it. We put new injectors and a new IP in it, and it still does it, we're just putting a new engine in because its too hard for us to find.

 

[suv7734]

So what does it mean if the boost is steady or jumpy?

-Rob

If you,ve got a valve guide that looks like #2 (pic by Jaybee) you will see the boost gauge 'flutter' or pulse ever time that cylinder 'fires'. The exhaust will also enter the valve cover causing a 'puff' in the blowby. The excess crankcase pressure can also cause seals to start leaking (rear main is common). In the case of an exhaust valve eventually the spring will lose its temper due to the heat and it's all downhill from there.

 

[Classicfordguy]

Well I guess that means it probably not a valve guide. The noise sounds heavier and louder than a I would imagine a valve could make. So I guess that narrows it to wrist pin or rod bearing. I doubt a lifter would make a nois this loud either.

Is there a way to check for a bad wrist pin or connecting rod bearing by pulling the oil pan or something?

-Rob

 

[f350flatbed]

Pulling the oil pan is kind of a pain in the butt. I just did it but you can see up in there.

Paul B