New injectors and still awful knocking???

[icanfixall]

Before you move the injection pump make a mark so you know where you moved from. Yes towards the drivers side is retarding it. Movement of 1/16th inch equals 2 degrees or a dimes width.

 

[Jake S.]

I have a bad lifter, must be the roller needles are shot. Sounds worse that a rod bearing. I pulled the valve covers and put a screwdriver on each rocker arm while it was running to find which one. The noise perfectly matched a rocker so it must not a rod bearing.

 

[Diesel JD]

Thing is that lifters and wrist pins have both been semi-weak points on the 6.9s. Again most of the time they don't break, just get weaker and begin to suck more and more till somebody fixes it or replaces the vehicle. Now a bad lifter is trouble. If you hang a valve it could be curtains for the motor. If you wipe off a lobe of the cam, you'll probably have to buy a new(rare part) cam and it will get annoying and expensive. If you send a sample to Blackstone, just save yourself the aggravation and ship it in a little box, UPS, FedEx Ground, DHL just not US mail. They never seem to deliver these in less than 2-3 weeks. Blackstone works fast once they get them. Tell them your concerns and they will look out for those materials more than usual. Let us know what comes of it.

 

[Classicfordguy]

SOrry it took me so long to post back, class started and those stupid ijection pump bolts are a pain.

Well I tried retarding the pump about 3/32 toward the driver side and the diesel knock got quieter but my mystery knock stayed the same. Tried advancing the same distance to the pass. side and the diesel knock got louder but the mystery knock remained the same. Now that I know what a louder diesel knock sounds like I know the mystery knock I am hearing sounds much louder and much more metalic.

Not sure how to gauge the amount of blowby I am getting, with the pcv hose off the air intake and the oil cap off bot blow a good pufs of whiteish smoke, if I plug both with my hands it will build some pressure after 8 seconds or so.

I hadn't thought of the daul mass flywheel but if you lay under the truck the noise is very loud as if it were comming from the DM or the oil pan area though if I do the screwdriver to the ear and touch both trans and oil pan I can't realy hear the nois. There is about 1" of slop in the DM but if I rotate it with the engine off it seems to hit springs in both directions, nothing hard. Also, the nois is still present when taking off from a stop and driving.

Any guesses?

Thanks again,

-Rob

 

[6 Nebraska IDIs]

If you've got a DMF thats real bad then it'll rattle and knock all the time. But here's the kicker, these DMF's wont go bad unless there was something aggravating it causing it to go bad.
I have a video of what my moms bad DMF sounded like.

 

[Classicfordguy]

If it were the daul mass wouldn't it stop knocking when I let out the clutch or accelerate?

Only other thing I forgot to mention is on cold startup the truck misses on one cylinder and blows a puff of blue smoke each time it misses. If you rev it for a second or two tha cylinder will begin firing just fine with no smoke.

-Rob

 

[Pipeliner_86]

Rob I believe our trucks have the same ailment. My 86 misses on one cylinder for about the first 5 mins. of warm up while puffing smoke. Then when it decides its warmed up the last cylinder starts popping and runs fine on all eight. I think maybe a valve seat prob, or worn valve guide. Heck, I don't know for sure, but it's been like this for at least four years now.

 

[6 Nebraska IDIs]

Yea, thats what I was trying to say. Its really unlikely that the DMF is bad. They get a bad wrap just because people dont know what they are diagnosing most of the time, and FORD stealerships LOVED replacing them because they cost so much to do, and thus lead people to believe that they are crap. They're not. They do exactly what they are supposed to. I have yet to see one go bad without having some serious engine problem causing it to do so.

 

[suv7734]

Not sure how to gauge the amount of blowby I am getting, with the pcv hose off the air intake and the oil cap off bot blow a good pufs of whiteish smoke, if I plug both with my hands it will build some pressure after 8 seconds or so.


Any guesses?

Thanks again,

-Rob

Just to be clear your saying that the blowby coming out the oil fill is puffing? It should be a steady stream at idle, something like the steam coming out of a boiling kettle on the stove.

 

[Classicfordguy]

Just went out and watched it again, it is not perfect, its a pretty steady stream that puffs larger every revolution as if one cylinder has excessive blowby.

Ya, I doubt it's the flywheel since it does not change when I drive.

Jeremy how loud is your knock? Does if fluctuate? Mine comes and goes at 8 or 10 second intervals and will go away for 5 seconds then slowly start making noise again. Its a pretty loud knock.

-Rob

 

[Ironman03R]

I have yet to see one go bad without having some serious engine problem causing it to do so.

What do you mean by that? I thought they would wear out over time since there are moving parts.
When we replaced the clutch in dads 88 it had around 100K on it and the DMF was shot from all the pulling that truck did over the years. Engine was fine when he sold it w/160K on the clock.
It was used for pulling a 350bushel Gooseneck trailer.

 

[Pipeliner_86]

Just went out and watched it again, it is not perfect, its a pretty steady stream that puffs larger every revolution as if one cylinder has excessive blowby.

Ya, I doubt it's the flywheel since it does not change when I drive.

Jeremy how loud is your knock? Does if fluctuate? Mine comes and goes at 8 or 10 second intervals and will go away for 5 seconds then slowly start making noise again. Its a pretty loud knock.

-Rob

The knock gets louder when theres no load on the engine, but somedays its louder than others. I think its quieter when the engine is cold. Once the oil warms up, I believe the knock gets louder. Somedays I dont notice it, and others I'm afraid to hammer on the truck too much.
I have another engine on the stand waiting to replace the 6.9 when it snorts for the last time. When that day comes......nobody knows.

 

[6 Nebraska IDIs]

I have yet to see one go bad without having some serious engine problem causing it to do so.

What do you mean by that? I thought they would wear out over time since there are moving parts.
When we replaced the clutch in dads 88 it had around 100K on it and the DMF was shot from all the pulling that truck did over the years. Engine was fine when he sold it w/160K on the clock.
It was used for pulling a 350bushel Gooseneck trailer.

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.

 

[suv7734]

You also indicated earlier that you had a boost gauge. When you're on the throttle and the boost gauge starts to come up is it rock steady or does it have a pulse or fluctuation/vibration to it? Sorry for all the questions but this sounds like something I've seen more than a few times but it's hard to nail down since I can't hear it from here. Funny thing is I was in Florida not that long ago

 

[jimraelee]

Whats that you all speak of??? Some type of dampener???