Crimedog

I tell ya HiD, with all you've put up with over the last year or so, it makes me want to come down there and be your dummy labor man! If you were closer I would be right there. Hopefully she purs real nice when she fires up again.

Haulin_in_Dixie

I fugured I would bring everyone up to date. No good news, worse. The truck is back together, with a different injection pump, a Dodge unit. Still knocks just like it did. I could not pull five and six in the truck, so the engine has to come out for a full overhaul.

The knock is on number three cylinder or at least breaking the injector nut elimiinates the knock. But there is nothing left. Looking for a truck right now, cannot shut it down to rebuild it, ran a load tonight with it.

With the Dodge vp44 the power is way down and the mileage is back to Dodge levels. Dodge vp44 produces about three pounds less boost and 150 less egt's.

Just for the record, injectors replaced, head replaced, vp44 replaced, 3 and 4 pistons pulled and replaced, bearings checked, bearings and rings on 3 and 4 replaced. Injector tubes replaced. Nothing left, must be a piston pin on number six which is the following cylinder. No piston contact or damage on any piston, cylinder walls perfect. All cooler jets in place.

Have to start from scratch I guess. I have my choice, come up with another truck or lose my business.

2500CTD

That sux man. It kinda makes sense that it might also be a piston following #3 in the rotation firing order. I suppose the best thing is to get another set of wheels. Know any friends that could do a loaner??

mhuppertz

I'd be tempted to go with a reman shortblock at this point just to get you up and running. If I had the money I would buy you one. I am so sorry that you are going through this. Prayers are in order....
Mark

Jason Foster

I would say just if you are not doing extremely long hauls, just drive it until it fails. You will find the problem then. If you have the money then have another truck on standby. Sorry it couldn't be simple.

SBishop

I am confused on why it could be a piston pin on #6.

If the knock goes away when #3 injector line is loosened, then it(the knock)can't be related to #6 can it?

Somebody help me here.

DustyRock

HiD: Sorry to hear of your trouble. Have been watching your posts hoping you would get er going. There is a 12 valve engine on E-Bay, its in Georgia here is the URL. Maybe this would work for you.

http://cgi.ebay.com/ebaymotors/Cummi...spagenameZWDVW

Dusty.

Haulin_in_Dixie

That is precisely what I thought and how I got to where I am, three weeks later and 1000 skinnier in the wallet.

turbox2

I hate to say it but it sounds like a wrist pin. I belive wrist pins knock under a pull and rods when u let off just my 2 cents worth

thumper 549

I am confused too. If at nu 3 the noise stops......it is related to # 3 is it not??
All thoe my brain says it probly a wrist pin and noisy wrist pins can make noise for years with no other trouble....so if it is a wrist pin let it ride, if its a rod,well it will tell you in short order in some other mannor. If it is a main it would be a completely dif noise..rumble thump vibration.
I vote fuel it the way you want and see what happens!!

turbox2

After reading all the threads this is crazy and no one deserves that kind of torcher a wrist pin should have showed up easy. Sorry Im shure we will all keep diggin.

TORQUE

After reading over all posts since my last posting, if #3 stops knocking when injection is cut out, there is a problem on #3 hole. When ignition takes place on the downward power stroke, cylinder pressures and force on piston are at their highest, and it will bring out any weakness/looseness in wrist pin and/or piston boss(crack), or also loose rod end bore or bearing causing your knock.

Unsure if Haulin has stated whether knock is worse when accelerating or decelerating, or if knocks all the time. This will narrow it down even more as turbox2 stated as to rod or wrist pin area. I would suggest looking VERY CLOSELY over all of #3 cylinder again top to bottom.

You can purchase crack detecting 3 step sprays to check for cracks yourself, or bring unit to Cummins shop or reputable/knowledgeable shop. Problem is there somewhere waiting to be found. Or swap out engine with exchange unit. In the interim maybe you can rent/borrow truck to help you get going again NOW. Good luck

Haulin_in_Dixie

Thanks for the response. The knock is deep and heavy, getting louder fast. It knocks on accel, none on decel. At idle it knocks quite loud now. A couple of days ago it was not too loud at idle but would pick up as the air compressor turned off and on.

there is nothing wrong with number three. Cummins have checked the piston and rod, just to double check me. Still the knock will quit with opening the injector nut.

Some hose sound testing seems to indicate number five as the source. I am setting up a more sensitive device with a real stethescope. Should have it tomorrow.

I have spent two days looking for a truck that I can get into. Missed a good one today, a 92 CTD with a flat and goose ball for 3600. It had just sold. Pickens are slim right now due to the rv movers to New Orleans areas. My son will be looking at a first gen ctd 2500 tomorrow.

jrs_dodge_diesel

HID, Sears has automotive stethoscopes designed for what you are looking for. They are pretty nifty, looks like a doctors stethoscope except where the dohickey that goes against your chest is replaced with a 10-12 inch steel (maybe aluminum) rod that you use to pinpoint the noise source. It directly pick up the vibrations off whatever you hold it against. I am going to be pulling mine out to track down a tapping noise I just developed in my engine.

BTW the stethoscope saved me some time on my old truck (1990 F150 w/300 I6) when that truck started misfiring. I was able to pinpoint the dead cylinder within 5 minutes.

EDIT : I forgot, the sthethoscopes range between 18-30 bucks.

12valve@heart

Haulin', what are your truck requirements? I know you built Murphy up quite a bit but there are a number of us who I'm sure would be glad to keep eyes peeled for you if we know what you are looking for.

If it were me, I'd look for a wreck and slap a used motor in Murphy to get you going while you give the other one the fine tooth comb but I'm sure that you've considered that. FWIW, I know where there is (as of 3 weeks ago) a wrecked '98 2500 5spd for $3500. Haven't gone to look at it but supposedly motor and tranny are fine.

Best of luck.