This car keeps kicking my ass and decided to ask for some forum help not only in my build thread.
I need to pinpoint this stupid rattle/knock in the engine I've been chasing for the past month an a half. I don't drive the car anymore because of it, only start it and warm it up once in a while after I change something.
Engine is a freshly built 3.0 m20, everything I could afford is brand new. It has covered over 3000 kms now and just recently developed a noise that wasn't there.
Here are some of the components built in, in case anyone can share some known issues with them
Bottom end
M20b27 1985 block
Low mileage m54b30 crank and rods
Low mileage m54b25 pistons, milled down for valve relief and CR
Kolbenschmidt rings
Brand new M21 oil pump
IE crank scraper dremeled to fit the m54 crank and rods
IE windage tray
Head
Slightly ported and polished 885 head
M40 valves cut and polished to match the m20 valve height
All new valve guides and seats (3 angle job on the seats)
Dbilas 292o Camshaft with 11.2 mm lift (2mm clearance to piston, measured with clay prior assembly)
Schrick dual valve springs
Vac Motorsports spring perches/retainers (are they called perches?)
Brand new rocker shafts
IE HD rockers
Brand new OEM eccentrics and hardware for them
Brand new oil tube
Nuke performance cam wheel (checked it for clearance to the bolts for the cam shaft seal - it clears)
Here are the symptoms and what I've done so far:
Symptoms:
Rattle when engine running, rpm dependent, not movement or under load dependent. It is there even if cold started (cooled down overnight). NOT there when I start the car after 4 or more days of not driving it, but by the time I switch off the lights in the garage, close the door and lock it, get back into the car, the rattle is already there - quiet, but already there. It gets worse when the engine reaches operating temperature. It got progressively worse/louder over the course of about 10 days of driving after the last track day. I can hear it pronounced listening from the top of the engine, less pronounced from the bottom with the car on the lift, but still loud enough.
On that trackday the oil DID get to the 150oC mark briefly, which is about 300oF, but the oil is now changed. Water temp never got over the middle mark.
Oil pressure is 1.3-1.4 bar (18.8 psi - 20.3 psi) when idling on warmed up engine and always has been.
The engine DOES have a windage tray and crank scraper.
No noticeable power loss ( nor gains as well for that matter :D )
What I've done so far:
Oil change (flushed the oil cooler too) - didn't work
Rocker arm eccentric to valve stem clearance adjustment TWICE - second time was on the engine 10 days not started, did them 0.25 - no change at all
Inspected the oil tube over the rockers - clean, oil passes through, isn't low enough for the rockers to hit it.
Checked as best as I could for rocker arm and eccentric premature wear (everything is brand new) - no visual issues
Verified following twice: timing, bolt on cam sprocket, jeesus bolt and crank sprocket too - nothing out of order
Cam sensor doesn't hit the trigger in place of the distributor.
Cam belt tight enough, not slapping about
Started engine without accessories belt - no change
Unplugged coil connectors one by one while engine running to listen if the noise would change - no change
Pressed gently against the clutch on warmed up engine - didn't feel it through the pedal.
Listening with a screwdriver from the top I can hear it between cyl 2 and cyl 3, when listening from the bottom on the pan - almost everywhere. Not on the block though.
Pulled the plugs, in order of appearance
What I still haven't done yet:
Compression test, but did one before this rattle emerged - average of 210 psi across all cylinders on a warm engine.
Check the drive pulley on the oil drive shaft (it is a brand new unit, the solid one, not stamped steel one)
Pull the pan and check bearing caps.
A short video:
So, if anyone has any input for me, highly appreciated.
I'm waiting on a tiny camera with an LED to stuff into the cylinders right now. But would like to know if there is anything else I can check before pulling the pan off. Really don't want to do that, figured someone may have had similar experiences.
Help, please
I need to pinpoint this stupid rattle/knock in the engine I've been chasing for the past month an a half. I don't drive the car anymore because of it, only start it and warm it up once in a while after I change something.
Engine is a freshly built 3.0 m20, everything I could afford is brand new. It has covered over 3000 kms now and just recently developed a noise that wasn't there.
Here are some of the components built in, in case anyone can share some known issues with them
Bottom end
M20b27 1985 block
Low mileage m54b30 crank and rods
Low mileage m54b25 pistons, milled down for valve relief and CR
Kolbenschmidt rings
Brand new M21 oil pump
IE crank scraper dremeled to fit the m54 crank and rods
IE windage tray
Head
Slightly ported and polished 885 head
M40 valves cut and polished to match the m20 valve height
All new valve guides and seats (3 angle job on the seats)
Dbilas 292o Camshaft with 11.2 mm lift (2mm clearance to piston, measured with clay prior assembly)
Schrick dual valve springs
Vac Motorsports spring perches/retainers (are they called perches?)
Brand new rocker shafts
IE HD rockers
Brand new OEM eccentrics and hardware for them
Brand new oil tube
Nuke performance cam wheel (checked it for clearance to the bolts for the cam shaft seal - it clears)
Here are the symptoms and what I've done so far:
Symptoms:
Rattle when engine running, rpm dependent, not movement or under load dependent. It is there even if cold started (cooled down overnight). NOT there when I start the car after 4 or more days of not driving it, but by the time I switch off the lights in the garage, close the door and lock it, get back into the car, the rattle is already there - quiet, but already there. It gets worse when the engine reaches operating temperature. It got progressively worse/louder over the course of about 10 days of driving after the last track day. I can hear it pronounced listening from the top of the engine, less pronounced from the bottom with the car on the lift, but still loud enough.
On that trackday the oil DID get to the 150oC mark briefly, which is about 300oF, but the oil is now changed. Water temp never got over the middle mark.
Oil pressure is 1.3-1.4 bar (18.8 psi - 20.3 psi) when idling on warmed up engine and always has been.
The engine DOES have a windage tray and crank scraper.
No noticeable power loss ( nor gains as well for that matter :D )
What I've done so far:
Oil change (flushed the oil cooler too) - didn't work
Rocker arm eccentric to valve stem clearance adjustment TWICE - second time was on the engine 10 days not started, did them 0.25 - no change at all
Inspected the oil tube over the rockers - clean, oil passes through, isn't low enough for the rockers to hit it.
Checked as best as I could for rocker arm and eccentric premature wear (everything is brand new) - no visual issues
Verified following twice: timing, bolt on cam sprocket, jeesus bolt and crank sprocket too - nothing out of order
Cam sensor doesn't hit the trigger in place of the distributor.
Cam belt tight enough, not slapping about
Started engine without accessories belt - no change
Unplugged coil connectors one by one while engine running to listen if the noise would change - no change
Pressed gently against the clutch on warmed up engine - didn't feel it through the pedal.
Listening with a screwdriver from the top I can hear it between cyl 2 and cyl 3, when listening from the bottom on the pan - almost everywhere. Not on the block though.
Pulled the plugs, in order of appearance
What I still haven't done yet:
Compression test, but did one before this rattle emerged - average of 210 psi across all cylinders on a warm engine.
Check the drive pulley on the oil drive shaft (it is a brand new unit, the solid one, not stamped steel one)
Pull the pan and check bearing caps.
A short video:
So, if anyone has any input for me, highly appreciated.
I'm waiting on a tiny camera with an LED to stuff into the cylinders right now. But would like to know if there is anything else I can check before pulling the pan off. Really don't want to do that, figured someone may have had similar experiences.
Help, please
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