TIMMEH

Okay everyone, I need some guidance for I have a rather bizarre issue that a lot of people are having a difficult time as to what this is. Actually I have several issues. Major gas consumption (I fixed it with a tune but it came back), low oil pressure (about 7 lbs at idle, 25 to 30 lbs at WOT at normal operating temp) and now this:

A while back I blew a chunk out of piston 5, and naturally the rings got trashed. I had a major header leak and a slightly blown head gasket. So, we rebuilt my motor.

8000 miles later, I notice a strange knock/grinding noise that intermittently pulses with the cam. I'm hoping it's a lifter but the noise actually got worse when I changed the oil. I pulled the spark plugs and what do I find? Oil on the plug for cylinder 5. Cylinder 3 is clean. Crap!

So last night I do a compression check on 3,5, and 7. Spark plugs were like this: 3 - clean, 5 - oily, 7 - oily. WTF? Gunk on 7?! Here's the kicker...compression test... 3 - 170 psi, 5 - 180 psi, 7 - 180 psi.

I've been talking to several people and they are leaning towards the valve guides for the oil on the plugs and the oil pressure problem...however it doesn't explain the horrendous metal on metal grinding/scraping noise that happens during the rotation.

I'm pretty sure I'm at the point of tearing down the motor again, but I was hoping maybe someone could lead me in the right direction of where to look first.

Cal

iTrader: (1)

Hmm sounds like another case of a turned lifter to me. You say "knock/grinding noise that intermittently pulses with the cam."

zamboxl

iTrader: (1)

damn dude if you gona rebuild i say just get a used engien off ebay for like $1.5k and be done with it.

Bill Bowling

iTrader: (6)

(about 7 lbs at idle, 25 to 30 lbs at WOT )

That oil pressure is real low at least conpared to mine. I usually run above 40 at idle and above 60 at WOT.

Bill

technical

Extra oil in #5 and #7 will explain the higher compression reading.
Pull the heads, they need to be freshened up any. Check the springs, rockers, and make sure the lifters are not turned like Cal stated.

TIMMEH

how would the lifters get turned? I'm kinda new at this so if they are turned, is it real obvious? Or would I have to know what I'm looking for to notice it?

Taspeed

iTrader: (1)

Lifters can't really be turned if there is not any metal shavings in the oil. he changed the oil and it was clean.

cueball

just an idea, but check the oil pump for the grinding noise, and low oil pressure.
the knocking noise is probably the oil in the 5-7 cyl. detonating.
any bodys guess for the oil in those cyl. could be valve guids, piston rings, oil in the intake, maybe combonation of bad oil pump,and valve guids because of low oil pressure.

Cal

iTrader: (1)

They somehow get turned while the motor is running. My theory is the plastic bends upward, and they come out the bottom of it. There is only one very small screw in the middle of this long plastic lifter guide to retain it. After this happened to mine, I made some steel brackets to put on top of them. I also drilled and taped the block for bigger bolts.

It's not real obvious to see unless you have the heads off the engine. Some people notice metal shavings in the oil, but I didn't. Maybe they were caught by the filter; dunno.

TIMMEH

Okay, pulled the heads this weekend, and the very first lifter on the driver's side (cyl 1) is totally FUBAR. The roller has chunks of metal missing, with about a 1/3rd of it still smooth. Looks like a small rendition of the grand canyon. However it wasn't turned when I pulled it.

I can't see the cam's lobe completely yet, but I'm sure it's got chunks ground out of it too. I'm going to pull the motor and do a rebuild on it. At least I found the grinding noise, thanks for your input guys!

OH, anyone know where I can get a replacement set of lifters for cheap?

TheBlurLS1

iTrader: (8)

comp 850 (OEM replacements) lifters should only run you about 195$ , DO NOT get the comp "R" lifters unless you have adjustable rocker arms, they require a specific preload.

you can get them from TSP ----->