adamiata

iTrader: (1)

My newly built motor started making awful rattling sounds 5 minutes into the first break in drive. I could use some help diagnosing the root cause and planning how to get my car running again. This was my first time building an engine and I thought I was careful to research before hand, maintain a clean assembly environment, follow good assembly procedure, check clearances, and torque everything carefully.

Engine is a BP6D with Manley rods, ACL bearings, ARP main studs, 9:1 OEM pistons, a BE oil pump, and dingleberry-honed cylinders. First startup and idle tuning were done on conventional oil, then changed out for Joe Gibbs break-in oil for the first drive. Warm up and idle tuning were uneventful.

I'm not sure what my oil pressure was, as I replaced the sending unit and the gauge was pegged at full-high - I think because I mistakenly used thread sealer on the new sensor.

All 5 main and 4 rod bearings show damage, either scuffing, scoring, or heat discoloration. The rod bearings are the worst, with bearings spun or horribly mangled. I also see flakes of material in my oil pan and on my oil pickup screen. I've not pulled the head off or gotten a good look at the cylinder walls, but a casual peak past the crank shows no obvious damage. Pics below.

Pic of plasti-gauge bearing clearance from assembly a couple months ago:


Debris in oil pan:


Sparkly oil:


Debris in pickup screen:


Spun rod bearing (cyl 3):


Damage to crank (cyl 3):


Mangled rod bearing (cyl 1):


Less severe damage to main bearing, but still scored:


Heat discoloration to outside or main bearing - typical for all five:


Where should I be looking for a root cause?
Is the widespread damage an indicator of an oil pressure problem?
Where do I go from here? What else should I inspect? Should I bother trying to salvage my crank, rods, and oil pump, or should I just start over?

Ted75zcar

iTrader: (2)

Did you use teflon tape as your thread sealer?

adamiata

iTrader: (1)

I used the liquid kind.

adamiata

iTrader: (1)

Had I lost oil pressure, I'd expect noise from the valvetrain too - which I didn't hear...

Ted75zcar

iTrader: (2)

Take a step back and consider the evidence. You have catastrophic failure in multiple locations that have only a few commonalities from a system perspective. You dismiss the datapoint of the pegged sensor, but a sensor will peg due to blockage, which can also cause this level of damage. In any event, the most likely cause is oil related. I personally would look for methods to test for fault conditions that result it a loss or lack of oil pressure at all of the failure points.

technicalninja

I'd look for oil pump sucking air; failure in pick up assembly- not tight, missing gasket, crack in pick up tube...
Or (more likely due to pegged OP gauge) a restriction in oil flow. Plugged galley, main bearing oil hole not aligning with oil galleys in block, etc.
Your bearings looked like they never saw oil pressure...

A machine shop needs to look at the crank but I like to start a high HP build with an uncut crank.
As long as you can source a good crank inexpensively I'd go different crank route.
Cranks CAN be machined and retain their strength but the machine shop has to be good and their crank grinder needs to be perfect.
Most are not...
Every uncut crank I use for a build DOES go to a machine shop that can micro-polish it. This makes the bearing surface smoother and reduces the cranks diameter a couple of tenths (.0001) which opens up the clearance a tiny bit.

andyfloyd

definitely lack of oil. The fact that ALL the bearings are hurt is very telling here.

Godless Commie

iTrader: (2)

* Why did you rebuild the engine in the first place?

* Were the oil galleries in the engine and the crank were cleaned thoroughly?

* Could you possibly have used silicone in a manner that could have dripped in the engine during assembly?

* Were the oil jets removed during the rebuild, and if so, were the mounting holes covered during the time they were out?

* Was a new oil pump used, and in either case, could the pump gears be damaged?

* Did you shim the oil pump, could the pin holding the spring in place have fallen off?

* Is the oil pick up gasket intact, ar are there any cracks, etc. on the tube that could allow air to be sucked in the pump?

* Could the bearing orientation be wrong? (See photo)

adamiata

iTrader: (1)

Thanks for all the replies. I'll take a close look at the bearing oil supply route as I tear the engine down further. I need to get a puller to remove the crank damper before I go much further.

I built the motor to be a ~250 hp street car, with some autocross and casual track use a possibility. I also wanted the experience of building a motor.

Engine oil galleys were cleaned with brushes. I did not clean the ones in the crank - a first timer oversight on my part.

I found more silicone inside the oil pan than I would have expected.

Oil jets were removed and reused. I did not cover their ports specifically, the whole block was wrapped up in a trash bag on an engine stand when I wasn't working on it.

New Boundary Engineering oil pump was used with additional shims installed by Boundary. I haven't touched them.

I'll take a close look at the oil pick today to see if the gasket is still there and look for cracks.

I'll check the bearing orientations as well.

GR124

I'm concerned about you not knowing the oil pressure. This is one of, if not the most important thing when starting a new engine.
The oil pressure is what holds the bearings away from contacting the crank journals.

You may get away with an engine shop polishing the journals and installing new bearings.
When you start it for the first time again. 1st make sure the oil pressure gauge works. remove the spark plugs, crank the engine a few times to make sure oil pressure is there, then start it.
Sad story, Good luck mate

gooflophaze

Did you forget to use assembly lube?

curly

iTrader: (25)

You will NOT get away with polishing the journals, you'll need to grind the crank .25mm/.01" on the mains and rods. That service costs me $180 at my local shop, done it dozens of times.

Make sure to throw your oil pump and stock oil cooler in the trash. The oil cooler will be full of bearing material you are unable to remove, and will ruin your next set of bearings quickly if reused. Talk to Travis about a discount on a new oil pump, he's usually kind to customers who experience bearing failures, since they wipe pumps.

You'll also need to do a VERY thorough inspection of your head, as the cams and/or cam journals may be ruined. If you think you can reuse the head, remove any and all galley plugs for inspection/cleaning.

The damage you've pictured is definitely in the "might be cheaper/safer to replace entire engine" category. Good luck.

adamiata

iTrader: (1)

First lesson learned: don't be an eager beaver for your first engine start. Don't assume a funky gauge reading is an instrumentation error just because you tampered with it recently. As I wrote above, my dash oil pressure gauge was pegged at full high, which I assumed was because I had replaced the sending unit with this supposedly equivalent VDO, moved the sensor to an oil filter sandwich plate, and wrongly used threadsealer. That's one thing I could have done to prevent this. Lesson learned.

Here's my oiling setup. Do you see any major no-nos here:?

Red is my replacement gauge cluster oil pressure sender installed in the sandwich plate. The new sensor is NPT, not BSPT, which is why I didn't put it back on the VVT line.
Blue is oil temperature intended for an aftermarket gauge.
Green is a three wire oil pressure sensor meant to talk to Megasquirt - not hooked up at the time of engine failure and a loose end that I planned to take care of later. The white stuff is liquid threadsealer that got squeezed out when I tightened the threads.
Yellow is turbo oil feed from where the OEM oil pressure sender is meant to go.




Thanks for input, Curly. I'll have a close look at the head. It'll be interesting to see what I find in the little mesh filter by the VVT solenoid.

I have a damper puller arriving on Friday, so I can get the bottom end apart and inspect some more.

adamiata

iTrader: (1)

Thanks for all the help so far, guys. I appreciate it.

My damper puller arrived and I tore the engine down further. I found two things that were out of the ordinary, but I'm not sure what to make of them:

• #1 oil squirter was hand tight. Could a leak here cause a loss of oil pressure that would explain all this?
• Oil pump relief valve was stuck in closed position. (See photo below) I disassembled the oil pump but could not get the relief valve plunger to move. With the shims and spring removed, I tried pushing on it with a long punch. It wouldn't move under moderate hand force. Does this jive with the failure mode and pegged oil pressure gauge? Could this be a defect that caused the bearing failure? For reference, pump is a Boundary Stage 2 bought shimmed from 5X racing.
• Main bearing oil holes were correctly aligned with block oiling holes. (see photo below).
• No obstructions found in block or crank oil passages. I pulled out the front oil galley freeze plug so I could see inside the block oil gallery while I poked a wire through all the oil passages without encountering resistance. Each oil squirter and main bearing supply was checked individually. On the crankshaft, I checked the passages between the main and rod bearing journals by dribbling WD-40 through and watching it come out the other side, which is imperfect but the best I can do without removing the ball bearing plugs.
• Oil pickup gasket was verified to be in place. (See photo)
• Oil pump output o-ring was verified to be in place, no obvious damage. (See photo)

Stuck valve, O-ring in place:


Bearing holes aligned with main oil holes:


Can you spot the oil pickup gasket in this picture?



@curly @Ted75zcar @Godless Commie @technicalninja @andyfloyd

curly

iTrader: (25)

If the valve was stuck in that position, it would just generate more oil pressure. Most likely if it's stuck there, it's a result of the bearing failure, not the cause.

The oil squirter could cause an internal oil leak, although if it were hand tight, I don't believe it would leak enough oil to cause the catastrophic failure shown in the original post. Remember the squirters themselves are 4 sizable internal oil "leaks", and the oil pump still has no issue generating 90 psi.

If you want to continue down the path of figuring out why this engine failed, you'll have to bring it to a qualified machinist to have everything measured, but even after that, the bearing surfaces may be damaged enough to not be able to accurately predict what happened.

Personally, as stated above, I'd grab the ARP hardware, rods, toss everything else, and move on with a new engine.

technicalninja

I still do not see a "smoking gun" reason and your bearings got "machine gunned".
I agree with Curly. I believe the block might be re-usable but...
Need pictures of the cams and cam journals. Curly was WAY right on checking the head as well, I should had mentioned that and I didn't.
So it looks like you had good / extreme oil pressure up to the sender and a severe lack of oil at the bearings. I'd look closely at your oil adaptor plate.
Is there any way it restricted the oil flow? Make sure to write "BAD" on the oil cooler assembly so no one inadvertently re-uses it.
Curly's advice is probably the least expensive way to solve your issues as going his route is usually cheaper than finding the individual parts.
If the head is damaged as well "whole motor" is the only economically viable route.
I'd have the rods checked/resized (machine shop) at a minimum and if they showed any color change (usually turns black or blue) I'd toss them as well.
Your rod bearings appeared to have "spun" and that is never easy on the rods...
Those ball bearings closing off the internal passages in the crank are damned near impossible to remove and I do not think they can be reinstalled properly. You could drill, tap, and plug them but you would want to rebalance the crank afterwards.
Way too much work...

Gee Emm

Remote oil filter? Crossed oil lines?

adamiata

iTrader: (1)

Thanks for the feedback, guys. I'll take a closer look at my oil pressure sandwich plate and re-check everything.

Sourcing a new BP6D is looking more expensive now than it was in June, mostly because of shipping costs. I'll have to hope that freight come down after New Years to get another motor and start over, or possibly source just a head and try to machine this block and crank - may as well bore it out and get forged pistons if it's going to a shop anyway.

Here's a typical cam journal and my the inside of my VVT actuator.

Ted75zcar

iTrader: (2)

That cam journal is ruff

engineered2win

I'd go back and check the oil pressure gauge. Determining whether the main oil galley was pressurized, or if you don't know whether the main galley was pressurized, will point you in a direction. Just cobble together a fitting to connect it to compressed air. Definitely looks to have lack of oil, which doesn't correlate with the gauge reading max.

How do the cam lobes look? If lack of lubrication, I'd expect the lobes to also be chewed up.
Definitely seems like something with the pickup or possibly the new pump wasn't able to self-prime. That would be plausible if the oil pressure sender is not reading correctly. It's possible it took long enough to prime that the assembly lube on the bearings was displaced, and at that point they're all running dry. And the damage is done, and it only took a short amount of time. The pump may have purged itself after that, but the clearances and surface finishes are already dicked. Some guys are pretty OCD about pre-oiling the engine with pressurized oil before first start.

I don't see what thread sealant would do to the gauge reading, unless you really globbed it on and it got in the communication port. I use thread sealant on all my pipe fittings, including sensors.