Hey guys,

I know I don't post much here, so I wanted to introduce myself first. My name is Paul, and I'm an N/T mod over at DSMTuners.com. I've used 2GNT as a tool for quite some time, but I've never felt the need to actually post a question here until now: searching has always yielded me the answers I was looking for previously.

Anyway, I have been spending the past week or so finishing up my rebuild project. What a pain! Luckily, I've had some good resources to fall back on in times of frustration (thanks again, Brian and Dino). Anyway, I finally got it started, but there's a knocking noise that concerns me - I narrowed it down to either rod knock or piston slap.

My whole rebuild saga is quite long, so I'm going to write down any background information you'll need in two versions: a short one for those who don't have much time, and a long one for those who actually care to read it.

SHORT VERSION:

After finally connecting everything to the engine, I tried cranking it over to get oil out of the oil feed line... nothing. I cranked and cranked and cranked. Finally, I dropped the oil pan and checked the oil pick up tube - it was fine. Then, before putting the oil back in, I started the car up to see if I got any oil then (d'oh). Luckily, I realized what I did and turned off the car in less than two seconds. I pulled the same stunt after I put the oil back in, and got oil in the feed line right away.

Now, I let the car idle, and this "knocking" sound showed up. It is still kind of audible after the car gets fully warm, and doesn't seem to be affected by RPMs (although, I never revved past 1500RPM yet).

Here is a link to a video of the engine running:

This guy is a boob....I have proof..lol

V, your the proud owner of a "slapper". Mine and DJ420A's are a couple of the same victems. I am loud enough that when cold you can hear me 40feet away.

The problem or situation rather is that the machinest built the motor for max clearance to avoid high boost causing the pistons to expand and sieze in the cylinder. Apply 15psi on a hot day and you will most likely notice most of the slap disappears.

Terry

I agree ^^. After rebuilding my engine, it sounded so freaken loud, i also thought something was wrong. After listening to that vid, that car sound just like mine. My rebuild has roughly 2k miles on it already and everything is fine besides a noticable oil leak that i have to fix (damn these oil leaks).

Of course the vid doesn't put out good sound, and you may hear something different being next to it, so I can't be sure, but this is just my opinion.

SoCal DSM
1996 RS-T: Under Construction
1999 GS AE: New daily driver
"USING NO WAY AS A WAY, HAVING NO LIMITATION AS A LIMITATION"--BRUCE LEE

Thanks so much for your input. I was afraid to drive it around until I knew exactly what I was dealing with.

To be honest, the noise doesn't bother me at all, I just wanted to know what was causing it.

It's such a relief to have this project finally done and over with.

Brian, what the hell is up with your videos? From what I heard, the engine sounded cool; but every time I try to open one of your video files, the picture breaks up and makes my computer really slow... Is it my computer, or your files? :p

Thanks again for all the input guys.

Ya thats slap, sounds the video clip I posted a long time ago...

I am too a victim of piston slap, however mine isnt as loud when its warm anymore.

-MIKE-

Stroked 2.2L

sounds like rods to me. Did you plastiguage the main bearings and rod bearings? if so what did you have. Do you hear a double knock? or is it just one knock consistently. Try a stethascope on the pan and then close to the cylinder. Did you measure your piston clearance?

"status as of now " busted420a powered by: 25g, crane cams valve springs retainers, ported head, ported manifold, oversize valves, 60mm tb, je pistions eagle rods, total seal rings,afx pulley, aem cam gears, spearco fmic, turbo xs bov, msd coil and wires, craptech

-MIKE-

Stroked 2.2L

Hehe,

Paul? (I think), Sounds like you got a case of the slap . Any chance they are forged? It really doesn't sound as bad as forged can sound. As long as you put plenty of assembly lube on the bearings (etc.) don't worry about the oil not pressurizing at first. The lube is your safety net (though you now know you should pack your oil pump). No problem with just polishing these cranks. I have reused with no prob.

Good luck on the break-in.

MB

Captain Caveman

96 RS Turbo 11.414 @ 119.62 MSNS, Crower 2 NA cams, BW366, 10.5 comp, UDP, 60mm TB, W/A intercooler, 3.55 tranny 567.9whp 430tq
97 RS NA 13.188 @ 103.87 MSnS powered 12.5 comp, Crower 3's and 219.4whp with 175tq
98 RS DD 12.5 comp on stock ECU, LTH, Crower 2's, Koni, GC, Hypercoil, DG hats
99 OZ 5sp Stocker 15.856 @ 85.97
99 GS stocker auto 17.7@77mph!

wiki home page:http://www.2gnt.com/index.php?d=bullettdsm

Thanks all!

I'm up to 220mi. (time for the first oil change) on the new engine, and break in is going well, so far. The knocking sound goes away substantially after the engine fully warms up, so I'm thoroughly convinced it is piston slap.

All clearances were checked by both my machinist and myself before anything was assembled. The crank journals were all within spec, and the rods and bearings, obviously, were all brand new.

The oil pump was sprayed down with white lithium grease (aerosol) and packed with assembly lube before I initially started it (I didn't have any Vaseline on hand). I trusted that the engine would probably be fine upon start up, but it was the turbo that scared me. I didn't want to run that thing a minute without oil... as it turns out, it was just fine running for a couple of seconds with no oil.

eclipse982nrRST, I read your threads from a while back, but I think the links to those videos are all dead now.


Thanks again everyone.