Oil pan pushed up against pump P/U=rod knock? (what is the Clearance on Rod journals?

flubyux2 · May 4, 2003

Well, a few weeks ago, our car started making noise like rod knock, especially while its cold, and even while driving after warmed up now. And before the knocking noises, it made a supercharger whine, like a Gear drive. VERY prominant after start up, quiets down a little after the engine has a little heat in it.

well, i ordered a set of STD rod bearings expecting to find some slop and a new oil pump gear set and front case cover to remedy my problem. Ever since we had the car (Jan/2002) the oil pan has always had a dent in the bottom, but i didnt think it was dented severely. My guess is someone tried to either jack the car up via the oil pan and block of wood, or they bottomed it out real hard, or they did something involving engine mount removal and engine support via floor jack. In any case, the dent was worse than i though.

I tore into my bottom end today, after fighting w/ the DP/cat-back bolts, then fighting w/ the T-case, easing off the Drvr X-member, Clutch dust sheild and finally taking the pan off (slathered in orange RTV...damn hill billies) i noticed that there was almost an IMPRINT of the pick-up head and screen in the bottom of the pan. It was so close to the pan i could see the cross-hatch pattern of the screen on the pan itself. I also found chunks of silicone and a small Rod down there about 2" long, bent on one end and what looks like a round disc that may have been broken off the END of that rod. i dont know where it could have come from or what inside the engine even uses a rod like that. Ill try to take a picture of my contents and the imprint of the pan and post it by tonight... or tommorrow.

anyhow, i tried to wiggle the 2 center rods of cyl 2 and 3, and nothing noticiable about the clearance, but i did have some noticable clearnace from side-to-side. Im not sure what the thrust clearnace of the big-end rod is supposed to be while on the crank, but id say its about .020-.030", is that normal? Ill try to get in there w/ my feeler guages when i have more time. Btw, what is the bearing clearnace supposed to be on the rod journals?

i bought red, green, and blue Plastiguage since i dont know what clearance im lookin for. Also, Should the rod bolts be replaced? i dont know of any torque-to-yeild rod bolts and im expecting to get by with reusing the rod bolts.

Give me some good input guys!

Thanks
Chris

Josh90TSI · May 5, 2003

Unfortunately, I think you will need a good rebuild. Sounds like you had some bad oil Starvation.

This is what my Manual states:

Connecting rod journal
Diameter: 1.771 inches
Out-of-round limit: 0.0006 inch
Taper limit: 0.0002 inch
Connecting Rod bearing oil clearance
Standard: 0.0008 to 0.0020 inch
Service limit: 0.004 inch
Connecting Rod endplay (side clearance)
Standard: 0.0039 to 0.0098 inch
Service Limit: 0.016 inch

Doesn't look good if your play is roughly .020 to .030 inch. Let me know if you need more specs. Good luck man.

Josh

EDIT- I reccomend getting ARP rod bolts, but it sounds like you will need more than just rod bolts. I have a 6 bolt bottom end in the garage, it needs work but if you're interested PM me.

flubyux2 · May 5, 2003

well i just plastiguaged the rod bearings and feeler guaged the side to side of the journals and everything checks out ok. In fact, the dull silver finish that is on the surface of the bearings when they are brand new is STILL on the bearings, there are only a few streaks where it has been rubbed away and polished. Every thing seems to be ok and was .0015" clearance and the side to side was all within .006-.007"... well within spec. Not bad for an engine w/ ~50k miles on it.

I have no idea where my noise could be coming from, but it sure isnt rod knock. Maybe the starved oil pump was just making extra noise. after the noise started, we didnt take it above 4000 or 60% throttle.

I wonder if its just lifters ticking cuz of inadequate pressure or soemthing... The rod i did find in the bottom of the pan is about 1.5" long, and 3/16"-1.4" diameter and it is hollow inside, about 1/16" ID, like its an oil passage or something. It is also bent @ a 45* angle on one end. So its got about 0.5" leg that is on a 45* angle, and the other 1" leg is straight. Its kind of nicked up, but i have NO idea where this thing could have come from... unless someone dropped it down into the pan from the top during maint.

colonelfox · May 6, 2003

It sounds like an oil squirter you found. There's should be one for each cylinder just below the bottom of the cylinder bore attached to the underside of the block.

mark93 · May 6, 2003

I bet the rod knock you are hearing is the balance shaft(front). When they start to go it usually sounds like rod knock.
There is really no way to find out for sure unless you take off the oil pump assb.

taz2w · May 6, 2003

If that a squirter, I bet the noise is from the wrist pin area.

flubyux2 · May 6, 2003

Duuuude, dont tell me that. now im worried... but i guess it also means Ross pistons and Eagle rods

I went to Satan yesterday and the did confirm my sus-pick-eons (suspicions). They tried to tell me it was PART of the Block itself. i said, no, i think its just an assembly bolted to an oil galley running thru the block held on by a banjo bolt and crush washers. and the guy was like "ooookayyyyy" and he had to look it up on his schematic.. and i basically said " i told ya so"

I sure hope its not the wrist pin. IT shouldnt have gone bad anyhow.. the NT cars dont have squirters and their wrist pins are fine. The oil squirters are primarily for cooling only, and the wrist pins should be oiled by internal passages in the con rod fed by the crank shaft.

And i would assume that it could be a Balance shaft also, but our car doesnt have any... hasnt had any for about 50k miles now. so it cant be that.

would an oil pump going bad make this kind of noise???

mark93 · May 6, 2003

ooops

TEC · May 6, 2003

flubyux2 said:
well i just plastiguaged the rod bearings and feeler guaged the side to side of the journals and everything checks out ok. In fact, the dull silver finish that is on the surface of the bearings when they are brand new is STILL on the bearings, there are only a few streaks where it has been rubbed away and polished. Every thing seems to be ok and was .0015" clearance and the side to side was all within .006-.007"... well within spec. Not bad for an engine w/ ~50k miles on it.

I hope you mean the babbit material that looks like thin gray plastic on the inside of the bearing, otherwise the bearings are shot.

colonelfox · May 6, 2003

taz2w said:
If that a squirter, I bet the noise is from the wrist pin area.

The squirters aren't necessary in the engine and wouldn't affect the oil supply of the wrist pins. Not enough to cause a problem anyway.
The oil pump could make that noise. Especially if a piece of foreign material, say from a squirter, got in the pickup.

flubyux2 · May 10, 2003

I hope you mean the babbit material that looks like thin gray plastic on the inside of the bearing, otherwise the bearings are shot.

uh, yea i am talking about the babbit. but teh babbit is the WHOLE top layer not just the thin film, then a copper layer, then the steel backing. the steel backing would be shiny, not dull. some manufacturers add other layers of their own special composition between the 3 main layers, but the 3 i mentioned are the main portions. Ive built plenty motors so i know the difference between severly worn bearing and a New bearing.

also, i still ahve the screen on my pickup, so that squirter would not have been able to make its way up the tube. I have No freakin idea how that thing would have broken off. I ordered some new squirters thinkin all were busted, but only #4 was, i replaced it in 5 min, and i was back in business. i rotated the crank by hand and tested the fit and there was no contact, so i dont see how it could have been mechanical interference. only thing i can think of is the Brazing just failed due to heat stress... but the squirter looks like it BROKE away and theres still a chunk stuck in the main body of the squirter. oh well, its back together, and im about to order an Oil press guage, im gettin an Ultralite Procomp... should i get mechanical or electrical??? the mech is like half the price of the electrical... is either one more accurate/reliable?

Smokehouse_83 · May 10, 2003

About were is the oil pressure gauge supposed to read at idle? Mine is half way between the bottom and the first line, I am wondering if my oil pan is dented, It looks like its dented by the plug, but I think its just the form of the oil pan.

flubyux2 · May 10, 2003

well i dont know exactly, mine never really worked right. i think its supposed to idle at about 12-15 psi though. if its much lower than that, you may have some excessive bearing clearance (worn out motor)

I just need to figure out which guage to get, cuz i dont trust the stocker at all.

sideshow76 · May 14, 2003

Sorry for the noob question, but what does Rod knock sound like? My pan is dented pretty good too, and I am just checking out posts. Thanks

JOEY

flubyux2 · May 14, 2003

there are a couple threads on here where a person posted a sound clip and a video clip of their rod knock problems. just keep searching cuz i found them last month. its hard to describe... and i cant even make the funny noises... all i can do is type them and hope you have some idea... or you could look up those posts

colonelfox · May 14, 2003

Imagine bad lifter tap only much louder.

Oil pan pushed up against pump P/U=rod knock? (what is the Clearance on Rod journals?

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