Engine/Transmission (1998.5 - 2002) Truck started knocking?!?

[JL penner]

figure I should post this here too





I was hauling the 3 horse, pulling around 65-70 mph when the truck stumbled a little, then started knocking. I never lost power, never got hot, boost was normal, exhaust temp same, not blowing smoke. I went another 10 miles pulling to get to my girlfriends house because I was late for a team penning. Truck performed awesome as usuall except for the knocking.



codes:



0460 - from having my rear tank (not related)

1693 - companion code (not related)



so no codes seem to be generating from this problem



What do I need to do?



TIA for the help

 

[JL penner]

started the truck back up (knock still there)



drove it forward and shut it off, let it coast in gear and the knock continues



I can't really tell if it's up high or down low.



Anybody know a good reliable diesel mechanic in the Temecula area?

 

[Bob4x4]

what brand oil filter are you running?



Bob

 

[JL penner]

fleetguard





oh, forgot to add my big oops



truck was a few quarts low on oil. Not really sure why it was so low, but as soon as i heard the knock, I pulled over and found it to be about 3 and a half quarts low!!! (Shouldn't I have seen my oil pressure drop???)



is this a possible cylinder score??



The knock never got worse when I drove it to my girlfriends house and back home again.



drained the oil and there appears to be no metal shavings

 

[AKAMAC]

Hopefully it is simple.

If it knocks at idle, use a piece of tubing with black tape wraped around one end to listen to each injector. (Tape end at your ear)

If one injector is louder than the rest, crack the fuel line to offending injector and see if the noise stops. (Beware of high pressure fuel spray, turn off engine to tighten)

May just be a bad injector... ... .

 

[Nate]

Acuatually that 1693 code means there is a code stored in the Engine Control Module.



I had that same code on my truck. Not sure if Cummins could get the codes or something?

 

[JL penner]

cracked all the injectors one by one and the noise stayed. (except #3, need a crows foot to get to it).







changed the oil completely, and no signs of metal shavings at all.



pulled the oil filter off and tore it apart. . no shaving anywhere







I attempted to pull the valve cover off, but couldn't get it all the way off. didn't feel like pulling all the insulation out. But from what I could tell, everything under it seemed to be intact. Wish I had a shop to pull it in to.

 

[Nate]

Yeah shop is nice, but I do all my work outside... in the 115* heat with the blazing sun or the "frigid" 10* winter weather... least that's what the locals told me. Said I must be on some drugs to be out in that cold.

 

[Graphic man]

i would pull the valve cover and have a look at the rockers to see if anything is wrong.

start with the easy things first.



Scott



keep us posted if you find anything

 

[JL penner]

I pulled the cover up (couldn't get all the way off) and checked everything out. The only thing I noticed is that there seems to be some play between the rockers and the valves. The only valve job I've ever done was on my little gasser truck (the one in my sig) and I don't recall allowing that much play.





Is there an easy way to pull the valve cover off that I'm missing?



Also how hard is it to adjust the valves in these trucks?





Thinking about doing this as well... ... Can the oil pan be dropped without pulling the engine?



I just would like to know what I'm in for before I send it to the cummins shop

 

[Alphacowboy]

there should be a hole behind the insulation to pull the cover bolt out, (heard the 01 and newer had the hole) if not, you have to take off the intake horn, APPS/TPS, and then you can shimmy it around and get it out.



The oil pan can be dropped, but you have to loosen the engine mount bolts and jacke up the passanger side of the engine IIRC.

 

[Kissfan113]

check the clutch man, I broke the pressure plate on my truck, it knocked like a rod, it did it at idle, in neutral, driving, got louder with rpms, my guess would be the pressure plate gave out on ya

Kevin

 

[Graphic man]

the cover will come off easy, move it to the left side of the motor as you take it off, there is a heater hose you have to hold it out of the way and it comes off easy.



i run my valve lash at 0. 008 int. and 0. 016 exh.



Scott

 

[JL penner]

check the clutch man, I broke the pressure plate on my truck, it knocked like a rod, it did it at idle, in neutral, driving, got louder with rpms, my guess would be the pressure plate gave out on ya

Kevin

Will there be any other indication with this? This actually sounds more like what it might be, but will my clutch start to slip?



Just got off the phone with Cummins, they said that if it's a scored cylinder, I'm looking at $8k to $10k worth of work, which means I'll drive it till it breaks then buy a new motor.



I told him all the symptons and he was at a loss for words. Said I should see some bit of increase in temp if there's a scored cylinder that's causing it to knock.

 

[JL penner]

okay, I started the truck after letting it sit since last night, here's what happened:



I could still hear the knock, but it got more quiet within a few seconds of startup. So basically, once oil pressure built, the knock got a little more quiet. To me this would indicate something like a spun rod bearing, but there seems to be absolutely no metal shavings at all in the oil??? I'm lost right now.



I'm trying to find a shop I can pull it into right now so I can drop the oil pan. I'll keep you guys updated, but please keep the advise coming!



Thank you all so much for the help so far.

 

[Kissfan113]

the clutch may completely go away, only other thing is to have the transmission taken down and everything inspected, mine didn't slip after it broke, i don't know how to best tell you to check it with the transmission still in the truck

Kevin

 

[WestTN]

You haven't used a Fram oil filter have you? If so, there may very well be a scored cylinder. The ycome apart and plug the piston cooling jets with RTV.

 

[JCutter]

Ive spun only two rod bearings in my life time and there wasnt any metal shavings in the oil that i could tell. Of course they were both on my beaters so the oil was black as tar and hadnt been changed in a year. I actually just replaced the bearings from junk yard bearings.



BUT I WOULD NOT TREAT MY CUMMINS LIKE THAT. It is my baby and i respect it well.

 

[JL penner]

You haven't used a Fram oil filter have you? If so, there may very well be a scored cylinder. The ycome apart and plug the piston cooling jets with RTV.

Nope, just use fleetguard



Just talked to my brother and he reminded me of the story on his truck. He went through the same thing with his. But he rebuilt his all by himself and said he only had to put $1700 into it.



I could probably do this, but I might need to track down a lift to pull the motor out with.



uggg... this has me wayyyy too depressed

 

[Graphic man]

i would not get to worried yet, you just need to find your problem... ... i had a bad knocking noise form the motor last week and we found a bad balancer $300 fixed it,



i used a stethoscope (automotive type)and i started from one end and went to the other end and we found it, i could grab it and move it back and forth 3/4 of an inch. cummins had 3 in stock.



just take your time and go over everything and i am sure you will find your problem.



Scott