Instant Rod Knock After Re-build - Oil to Bearing Problem?

[BoostedFloto]

Ok this might be a little long but need to type the whole history. I’m at the point of parting it out and need any thoughts or insights on the situation.

Ok, bought my supra with the engine already pulled because of rod knock. Took the engine apart and to the machine it went did everything they recommended for it. In the mean time my stock-ish rebuild kept snowballing into a full on build (check my build threads if you wish). So motor got put back together and dropped in. Drove it to get the exhaust made up had like a ¼ downpipe for it. Got home from that and started noticing some noises couldn’t identify it. We thought it was the head yada yada. So eventually out came the motor and flipped it over and the main bearings were scored up pretty good with some damage on the rod bearings (this was all with the same rods and etc from the original engine).

Well since I had already went T66 FFIM etc etc decided screw it should’ve done forged anyways so lets just go forged. So bought a brand new set of Crower Rods, Titan Main Caps, Wiseco pistons. Went to a Machine shop in Orlando recommended by Titan. Took everything there and explained what we wanted etc. So he assembled the rods/pistons balanced everything bored the cylinders, cut the crank so on and so forth. He couldn’t do the align bore of the billet mains so went to a respected shop in Tampa for that.

Got it all back and put back together with ARP hardware everywhere. Mains torque set to 80lbs and Crowers torque set to 45lbs with a brand new torque wrench. Got it all installed started it up and at about 30-45seconds hear a ticking noise but had very good oil pressure and throttle response.

We thought for sure it was the valve lash measured it and it was all messed up. We fixed the lash and still had the ticking noise. We then had some people listen to it everyone was like oh that’s forged noise. I didn’t believe them and knew something wasn’t right. Pulled the motor again took rod cap #1 off and it looked like this :

……with a small piece of metal welded onto the crank

#6 rod had some damage

and the others had some early wear, all the mains looked to be good. So I was extremely pissed at this point and then we found out about the Crank plugs that we didn’t know about needing to be cleaned.

So figured that was the problem. Took it all back to the machine shop and explained what happened and gave them the entire rotating assembly with a fresh stock un-molested crank. Asked them to cut it 10/10 check the main bore, the cylinder bore to clearance the bearings balance the new crank replace and clean the plugs etc. Got it all back put back together and same freaking identical thing instant noise at about 30-45seconds. Haven’t taken it apart yet to see the bearings.

Someone was being a smart ass and was like the rods are backwards which triggered a thought process and after extensive research and looking at all my pics we’ve determined that the machine shop did in fact assemble the rods backwards. The notches for the bearings were on the exhaust side not the intake side like they should be.

So that being said would that cause instant knock/noise like we are getting. If not what else could be causing some of these issues. I can’t keep spending money on a wild goose hunt/trial and error.


Cliff’s:
2 instant rod knock engines after assembly of forged internals, Machine shop assembled the rods/pistons backwards and we didn’t realize/think to check it. Could this cause an instant knock.

Any other ideas on what would cause instant rod knock.

Before you start saying I don’t know what I’m doing I’ve had people who have built a lot of these motors over pretty much doing majority of the work and all torque spec’s followed to the “T”.


Any help/thoughts would be greatly appreciated!

 

[jdub]

The top pics look like cavitation erosion caused by air bubbles combined with debris in the oil. Both show signs of debris damage. The shiney spots along the edges point to excessive shoulders on the crank journals. Do they all look like this?

Was assembly lube used? Did you pack your oil pump with light grease? And, turn the motor over with the EFI fuse pulled before cranking? Since this was the 1st shot and your crank oil passages were not flushed, that could easily be the cause of what I'm seeing here.

Did you go through your oiling system to make sure all lines are routed correctly?

 

[Idealsupra]

The top pics look like cavitation erosion caused by air bubbles combined with debris in the oil. Both show signs of debris damage. The shiney spots along the edges point to excessive shoulders on the crank journals. Do they all look like this?

Yes we agreed on this assumption. These bearings were from the original forged build instant knock failure. We forgot about the crank plugs after having the crank cut. So we figured that was the issue. Then this build we used a different crank that wasnt touched yet. Had a machine shop cut it to 10/10 and clearance the rod and main bearings. We also had them clean ou the oil passages. Once we got it back we also took brake cleaner and air from the compressor and cleaned out all the oil passages some more. We have yet to pull the engine out to check the bearings from this most recent build. However it is making the same noise as it did when the bearings looked like this from the last build.

Was assembly lube used?

the build that these bearings came from high viscosity oil was used during assembly. for the build that was just put in and made the same noise permatex assembly lube was used liberally.

Did you pack your oil pump with light grease?

The oil pump was flushed out with brake cleaner both times. No grease or oil was put directly into it however.

And, turn the motor over with the EFI fuse pulled before cranking?

Yes. the first time it cranked to about 30psi and then we put the EFI fuse back in and let it turn over. the second time pretty much the same thing except the pressure was about 15-20 psi.

Since this was the 1st shot and your crank oil passages were not flushed, that could easily be the cause of what I'm seeing here.

I would agree with that for the last build that had the debris and problems. However this most recent build had everything leaned and flushed out etc... so what could be the cause of the instant knocking that sounds exactly like the last one?

Did you go through your oiling system to make sure all lines are routed correctly?

All lines are routed correctly. Its basically a stock oiling system. It has a modded oil pump done by Soapra on here. And a DM AN/SS line from pump to block. After that its all stock stuff.


Any ideas? Im fresh out of them and am getting frustrated.

 

[jdub]

It could be a completely different cause...you'll need to pull the bottom end to see. Pay attention to the holes in the main bearings...are the oil holes lined up and there was no shift in the bearing.

The mains, did they show any damage like this? And, did all the rod bearings show the same thing?

 

[IJ.]

Almost 6 thou Piston to Bore on coated pistons may be the issue this time

 

[jdub]

Ahhh...good point! Good ole piston slap?

 

[Idealsupra]

Almost 6 thou Piston to Bore on coated pistons may be the issue this time

Ahhh...good point! Good ole piston slap?

Well my question would be if it is infact piston slap... wouldnt it go away or at the least quiet down once the car is warmed up? Cause this doesnt.

I guess it just needs to be pulled and see what the bearings are like.

 

[BoostedFloto]

If the bearings were a fluke last time and this is all piston slap.

Why does it take 30-45seconds to start and not immediate?

Also does piston slap follow throughout the RPM range and so audible that you can hear it driving down the road ?

 

[jdub]

Well...it was a thought. That is a big piston to bore for coated pistons...it's going to take them a while to heat up and expand. On my Ross pistons, the slap takes 15-20 minutes of constant driving to completely go away for the same reason and same clearances, but mine are not coated.

What about my questions from Post #4?
In addition, did you make sure the oil channel running down the exhaust side of the block (the one the pressure sensor is tapped into) is clear?

 

[Idealsupra]

It could be a completely different cause...you'll need to pull the bottom end to see. Pay attention to the holes in the main bearings...are the oil holes lined up and there was no shift in the bearing.

The mains, did they show any damage like this? And, did all the rod bearings show the same thing?

Yeah pretty much have to see what the bearings look like when its pulled.

The mains looked a LOT better. However they showed a LITTLE bit of wear for only have 40 miles on them. But no copper showing or anything like that. I THINK Bill has a pic or two of the bearings but not sure.

As for the rod bearings. They all had some sort of wear on them like the ones pictured. However number 1 was by far the worst and number 6 was probably second worse.

Well...it was a thought. That is a big piston to bore for coated pistons...it's going to take them a while to heat up and expand. On my Ross pistons, the slap takes 15-20 minutes of constant driving to completely go away for the same reason and same clearances, but mine are not coated.

What about my questions from Post #4?
In addition, did you make sure the oil channel running down the exhaust side of the block (the one the pressure sensor is tapped into) is clear?

The block was hot tanked the first time (new aux driveshaft bearings and freeze plugs installed after obviously), and this second time it was brake cleaned out as much as possible.

 

[BoostedFloto]

To give some perspective of noise and heat up.

On the first forged build: Drove it about 20miles to a local shop on the highway to use their lift for something unrelated. That drive took 30-40ish min... Car cooled down used the lift and what not Then was headed back home with a friend from the shop in the car to also listen to the noise. Same distance and time frame. The noise is soooo loud that while cruising at 75mph on the highway during certain RPM's could distinctly hear the noise. Also seemed at that time to be somewhat load dependent meaning when we heard the noise would hold the rpm's at that point push in the clutch and the noise would disappear. Now that being said also while the car is idling and we slowly rev the engine up the noise will follow the rpm's....

So can that be consistent with piston slap ?

 

[jdub]

Piston slap should have quieted down by then...unless it's really, really severe.

Guess you'll have to pull it...it's got to be in the oil system some where.

 

[BoostedFloto]

Yep....motor is getting pulled maybe this weekend. I'm just looking for an answer or something that we have been retarded about that is causing this. I cant justify another trip to the machine shop to try it again unless I know something we could do differently. I really don't want to part it out but I can't keep on this trial and error shit gets expensive.

So in an EXTREMELY bad case of Piston slap would you be able to hear it at 75-80mph on the freeway?

I know it is all speculation until I get the motor out.


Just kinda lost at the moment....Thanks for the input!

 

[Idealsupra]

bump for answer to bills question.

 

[a_sesshoumaru]

i got piston slap a few days back in fact i am puting my new pistons this week, i started the car with no problem, 100miles later a knocking noise started, another 80 miles the noise was so loud it sounded like a severe case of rod knock,it is rev dependant, the more you rev the louder and faster it gets, you can tell if that is piston slap, get a car stethoscope, the sound is louder between the cylinder head and the block, and it focus in the cylinders more damaged. (i have three good ross 0.17 pistons for sale if you need them :biglaugh

 

[IJ.]

Jay: Is the motor puffy at all if you pull the Oil cap and bring the revs up?