decadecivic

iTrader: (2)

I did the hard break in + initial tuning. Before tuning, my AFR would be at around 15 from low to high loads and WOT, sometimes even jumping up to 17. My break in consisted of 3 sets of 3 pulls at 50%, 75%, and 100% throttle at 2nd gear. Someone has told me my break in was done wrong and shouldn't have been done with 2nd gear but 3rd for more consistent load across RPM at steady TPS. At the end of the tune, my low load is aimed towards AFR 14.7, ~13.5 at mid loads, and ~12.5 at high loads >100kPa. During those pulls, I assessed the AFR and adjusted fuel accordingly to richen it back down, but had moments where, at WOT ~6000RPM, I would be at ~17 AFR for good 1.5sec.

After the 9th and final pull, driving back home, I noticed through the stethoscope there was a distinctive rattling or 'clacking' sound at the same frequency as the valves. This sound would start to come on at around 2,800 RPM when giving light/moderate throtttle, depending on gear. The cyclic noise sounds just like the valves, except louder. The next morning, starting the car up, I heard this clacking sound during the warm up, even without my steth on. Tugging on the throttle cable, I could induce that rattling sound. After a quick drive/tune around my neighborhood, I forgot and didn't check to see if the rattling sound was gone after warm-up.

At this point in time, I'm pretty upset and downed about the noise. My prediction is all over the place: rod knock, piston slap, valvetrain?, or too advanced timing?(as claimed by someone).
My prediction for the cause is also uncertain: too harsh of a break-in early on, floating at 17 AFR for those short moments at high RPMs, or poor installation of pistons & related components.

Gonna leave the car as is for the while and do more research.

dbang003

i've checked for rod knock by turning the motor over by hand, getting the cylinder in question on the downstroke and then pushing down on the piston thru the spark plug hole with a screwdriver. if it's bad enough you'll be able to push the piston down a bit because of the bad bearing. also can diagnose what piston it is by pulling plug wires off the plug one by one with the motor running. you'll be able to hear what plug/cylinder causes the knock to change frequency.

video_voide

Reversed end cap?

Don't go yanking the head just yet. Go slow.

Did you detail the thrust bearings installation?

decadecivic

iTrader: (2)

After 11 months now, I finally begun working on the car again. Until now, work and procrastination/laziness kept me from doing anything. During the time after my previous post, the rattle noise persisted more and more. I decided to stop attempting the tune, and stored the car. As well, I noticed oil leak on tranny side. So far, I took the motor out of the car and disassembled everything. I discovered that Rod #1 spun a bearing.

The oil pan shows signs of bearing failure. Shiny gold flakes.



Removed the head reveals an odd oil burn mark on the intake side of the pistons. The stock PCV EGR system has been deleted with my DIY oil catch can breather, so shouldn't have this kind of pattern.



Main seal looks okay. It seems like the source of the oil leak is from an improperly installed rear seal. It could have been driven in deeper.



Removed girdle. Pictures of main bearings from 1 to 5 (Main to Rear).






Rod 2, 3, and 4 look okay, but #1 doesn't look good. The main end has play. There is also an appearance of heat treatment tempering, from the array of colors shown on the end cap only.


The amount of play present.


Removed end cap


One of the bearing halves. There is a chip at a corner.





Rod journal. Running my finger nail longitudinally along the journal is bumpy like a mediocre milling surface finish.




2nd half of bearing. I noticed just how thin and worn down it is. Also, the center of the bearing is wider than the ends, like it was squished.





Bearing surface of the rod




Measured both bearing halves to see how much it was squished.
1st half: 0.781" vs 0.881"


2nd half: 0.775" vs 0.852"

decadecivic

iTrader: (2)

Other halves of the main bearings #1-5






More detailed pictures of spun bearing rod journal. The other rod and main journals look fine.



All the remaining rod bearings don't look and feel good. I can feel some grooves when I run my fingernail across the all the bearings. All the bearings have asymmetrical wear; 3/4 of one side would be worn down shiny while 1/4 of the remaining side is still matte, like brand new. One of the bearing halves from rod #4 has the worst damage of all—deep gouges on the bearing surface.

Pics of each bearing halves.

Rod #2



Rod #3



Rod #4



I should've recorded down my plastigauge measurements during my assembly, but I feel like my bearings were oversized if I vaguely recall it. Another possibility to these damages are the DIY chamfers I added to the oil galleries on the journals. I rubbed my finger around the openings of those oil galleries and could just barely feel minute roughness; perhaps it became that way after the machine shop polished my crank journals.

I'm assuming I'll want all these bearings replaced, this time more stringent on clearances. While the crank is at the machine shop, I'll request them to deburr the oil galleries and repolish all journals.

Anyone have thoughts on the wears on the bearings?

mattbatson

how is the aerodynamics development/business coming?
I remembered this thread from a while back and at the time was intrigued...

decadecivic

iTrader: (2)

At this moment, everything are designs on CAD and simulations. I need my car up and running before I mock up a prototype. I've also been working on designs for a BMW E36 and NA1 Miata. I have been procrastinating too much and need to jump back to it with more attention.

decadecivic

iTrader: (2)

The oil spots on the intake side of the piston is still worrying me. If the oil did indeed come in from the intake, then the only way it could be introduced there is from the valve train. The stock PCV system has been deleted and sealed. I'm wondering if the valve seals are spoiled and not good quality, and maybe allowing that oil to be sucked in by manifold vacuum.

decadecivic

iTrader: (2)

I went to a machine shop and after initial inspection of all the parts, here's the following report:

-Measurements show the crank is bent. There's at most 0.005" of a run-out.
-One of 3 remaining healthy rods has the metal bushing for the wrist pin knocked out. It is just dangling around the wrist pin right now.
-The mating surface of the rod and end cap for the spun bearing rod is still okay to be reused
-The PTW clearance is too tight. There is wearing on the teflon coating on the upper part of the skirt.
-The cylinder that spun out did not have the notches grinded out deep enough, there are marks of the rod hitting the cylinder wall. It is believed that after spinning out the bearing, the loose rod was able to hit the wall.

Right now I'm going to harvest the crank off another Z6 motor. I'm also inquiring P2P0 about selling just that brass-colored bushing.

decadecivic

iTrader: (2)

I've got everything back from the machine shop and had the engine assembled, put in the car, and ran the car on the road again. The new machine shop did a better job than my previous, they're more engaging and suggestive in consulting parts and service recommendations. Credits to Terry and Donnie from Terry Bride Racing Engine & Machine.

-I pulled a healthy crank from a $80 d16z6 and got the journals polished.

-The machine shop confirmed that the rod's inner diameter was too small and caused the bearings to be squished out of circle, therefore causing my spun bearing. IDs on all rods have been opened up. Having the rods check is something i didn't do at the machine shop the first time around, lesson learnt.

-Because the PTW on the old piston was too much, new set of stock vitara pistons was bought and installed.

-The valve job done by the first machine shop was no good, 2 valves were leaking. The new machine shop vacuum checked and fixed them.

-A new brass bushing was made for the rod that had its factory one fall out.

-New bearings for rods and mains were purchased. I had the machine shop measure up the desired tolerances and purchase the bearings.

-During assembly, I reused my head gasket, adding permatex copper gasket spray.

After everything was installed back on, I did my 10min idle break in, oil change, and followed by medium to hard loads/engine breaking to set the rings. The tuning process was a lot smoother this time around and I'm getting AFR figures I like, thanks to tips from MDA Fabrication. Despite getting the AFRs I want: 15 for idle, ~14 for 25-60% throttle, and ~13.2 for WOT. My CR is ~8.5—based on stock head, stock vitara piston, and p2p0 rods.

I went for an emissions test (AirCare) after tuning it. I bumped the AFRs to be a bit leaner than what I wanted, but still ended up failing. I passed NOx with 1.18 out of 1.24, but failed CO with 20.5 out of 9.32 and HC at 1.13 out of 0.5 (All units in g/km). It's so agonizing.

shotoutacc0rd

dont let it get you down man. I enjoyed reading this and I'm confident you're gonna get this **** down and so to say knock it out of the park. You've got alot of patience to have the engine crap out and then fix it back up, the 9 month reprieve prolly helped but most guys would have sold the rods sold the head and block. Stick with it and you'l have a nice racecar in the end.

good luck passing emissions regulations, thats a nightmare.

decadecivic

iTrader: (2)

Great news and Horrible news.

Great news:
A Honda tuner got me to pass emissions test and the car is back on the road. I'm now 300km into the break-in

Horrible news:
Rod bearing spun again. Depressed. Fingers pointed at oil pan, oil pick-up, oil pump, or somewhere oil gallery.

decadecivic

iTrader: (2)

Oil Pressures:

Cold start idle, jumpy needle 70-80psi

Radiator kicks in, fully warmed, 15psi

decadecivic

iTrader: (2)

I took the pan off, and see the bearing flakes. Cylinder #1 spun out again, this time with a different rod though. The spun rod is a lot worse than the first time, the cap is now blackened.

Leak down test shows excellent reading. no problem with rings, head gasket, and seals.

With the oil pressure registering 15psi on a spun bearing, it seems the oil pump is fine.

The ID of all the rod's big end has been turned to the correct diameter so it wouldn't squish the bearing awkwardly.

The first time I spun a bearing, it was after I did 3 pulls up to near 8000RPM, that I started hearing and noticing the sound. By that point, the motor probably only had 50km on it.

This second time, I have 300km on it, and I started noticing the sound after multiple pulls to near 8000RPM in the span of 150km.

What is going on with my motor? Why rod journal/cylinder #1?

eastbay92cx

That oil pressure sounds like too high, I guess that's good.

Is the crank straight? Are the journals round?

Original crank and main caps all from the same block?

'Yes' would be good for these questions.

The car was tuned right? Not too much timing, no detonation?
Was the crank turned or the block line honed? Did they do it right?

Repeated spun bearings, maybe something is not straight or too much ignition timing. Did you use plastigauge or measure the clearance and roundness when installing the bearings?

Sorry more questions than answers, hope you get it figured out.

decadecivic

iTrader: (2)

Crank was straight when installed. Journals were round when installed. All bearing clearances were measured with mics. Everything confirmed and done by machine shop.

Girdle is from same block, but crank was replacement for the previous spun bearing.

The car was tuned by a reputable tuner, should be fine.

decadecivic

iTrader: (2)

I was at fault and completely clumsy for the second rebuild.

The rod bearing spun because I installed rod caps with opposite facing tangs. All rods had opposite tangs and the Cylinder #2 rod has signs of spun bearing. Hella-*******-fail.

Replace crank, block is still reusable, all pistons are measured to be reusable, will purchase entire new set of p2p0 rods, new bearings, replace oil pump, and replace oil pick-up.

decadecivic

iTrader: (2)

Share a bit of what I've been doing regarding my aero-kit:

OMG THE GOGGLES

iTrader: (7)

GL with rebuild. Very cool aero designs btw!

decadecivic

iTrader: (2)

I've got the car together and its running again.

I've got 470km on it so far and upon getting an oil pressure reading now, I'm getting 13-14psi hot during idle at 1000rpm. This was measured with a mechanical Snap-on.

Some say my pressure is too low and recommend I swap a new, unmolested oil pump (since I've reusing the pump from the last 2 spun bearings). Others have suggested that my psi is above OEM spec, which is 10psi minimum, but that's probably at a 700-800rpm stock idle, I think.

And I also got pulled over and issued a ticket for a vehicle inspection. Cause was likely had-a-bad-day cop, my yellow headlights, and my poked wheels. How annoying.

king06

iTrader: (1)

Keep it coming. I would have given up after the first spun bearing.

scottdh20

I love it, keep at it man

areo looks sick, is there a reason for the rear supports attaching to the top of the rear bumper or is it just the picture im looking at wrong?

I like the wing supports on the top of the wing which helps keep the air under the wing clean

decadecivic

iTrader: (2)

Because of the low oil pressure, I decided to rip off the pan and inspect the cause of it.

After checking out all the bearings, they are worn slightly from the lack of oil pressure. During my drives leading to this point, I noticed very slight rod knocks through the det-cans. Inspecting the bearings, Rod #1 begun knocking and the bearing was wearing down, luckily did not spin yet. Crank journals are fine. Thrust washer show minimal wear on the rear side (likely from clutch+no oil)

Inspected the pick-up and noticed some bearing flakes. Took apart the oil pump, and gears show signs of aeration. I inspected the port on the pick-up closely and noticed the mating surface was concaved and not flat, meaning air has a passage way to seep into the pump.

So far, I've ordered a new pump, new main and rod bearings, and pick up.

Anybody else experienced a concaved port on the pickup before?

decadecivic

iTrader: (2)

Rod #1

decadecivic

iTrader: (2)

I changed the bearings, oil pump (rockauto), and pickup (oem).

In the middle of changing the pickup, I realized too late that I was running an A6 pan with a Z6 pickup, thus during the first 5 min of my startup, I had low to no oil pressure, and was knocking my rods. Raising the rpm did nothing to raise the oil pressure.

I swapped over a z6 pan, and now have oil pressure building up, but the pressure is still low (70psi right at start, and 10psi after warmed up). The knocking sound stopped but is replaced with irregular clacking sound that is proportional to rpm. The way it clacks is almost like a loose bolt or nut flying around and hitting something. I reved the car up and down to 2k rpm and pressure builds up to 40psi. After 8min of this, in my last rev up to 4k, my engine just stalls. I have a short clip video of that happening as I was attempting to capture audio of the clacking.

I took the valve cover off, camshaft lobes look fine. I took off the spark plugs, they look fine and pistons look fine. I turned the motor by hand, nothing feels jammed, no noise either. If I try starting the car up, the starter motor doesn't sound right. It sounds like it's not rotating fast enough ... like it is weakened or something in my block assembly is giving more resistance. At the time I encountered all this, it started raining pretty bad, I'll drop the pan, and check out the starter motor another day.