engine knock bad!!

[JTS VENOM PERFORMANCE]

sicne all you did was heads, I really dont see it being the bearings , but the low oil pressure does seem to indicate a bearing problem along with the noise comming from the bottom end,

and you leak down numbers isnt well either, probably got a combination of different problems all together.

what will it take to fix it? you cant tell until you either look inside the bore at the top of the pistons and take the pan off and inspect the bearings.

 

[Prof]

If the ring lands have gone away (which has happened to lots of us, but mostly under forced induction) that would cause the blow-by and the loss of oil pressure.

My bet would be that you have the ring land issue and that a chunk of the land got in the wrong place and you may well have a spun main or a bent rod.

Don't panic...get some estimates on a re-build...you can find builders who will do the work in a conservative manner and you might be surprised how quickly you can be back up and running...it may even be affordable.

Call Tony before you do anything rash...talk to him about the options...please!!!

Here is what to look for when you pull the pistons:

Sorry...here are a couple...but you will have to pull the pistons to see this kind of damage...but if you scope it you will see the "diamond mine" on the top of the pistons and that is an indication of detonation which is what causes a non-forged engine to destroy the piston lands...

 

[500H V10]

Just a thought could this be one of the early engines that had the camshaft bolt coming loose issue??? Even your best comp. test #'s seem low to me. This is a high compression engine 9.6 to 1. Unless you have a radical cam bleeding off some pressure your #'s should be higher. I think the cam bolt coming loose could effect the timing to the point of some valves getting bent and leaking. I would check the Vin # to the early engines that were recalled to see. Ultimately the Leak Down test will tell you if it's rings leaking or valves. Listen to the breather cap for air, then the intake (open throttle) and last listen to the exhaust pipe for air. You will find the problem area once you perform the Leak Down test.
Good luck,
500H V-10

 

[WOT]

Piston problems won't cause low oil pressure. The pistons are not pressure oiled.

However, a bad main bearing will make that exact noise at idle. Rod bearings make a much faster rattling sound and typically won't rattle at idle. Main bearing make a slow steady knocking sound that increases with engine RPM. They cause low oil pressure, low pitch knocking sound, and are detrimental to the rest of the motor.

I've had several motors over the years that have developed bad mains. They start out sounding like an exhaust leak, but will get usually get more pronounced over time. An easy way to check if this is the problem is to put some super thick oil in and see if it goes away. You could change the oil with straight 60 weight Valvoline. Autozone usually carries this. If it stops knocking on cold start up, it is a bearing for sure. As the oil heats up, it will likely start knocking again.

Then you know you need to pull the pan and take a look. Hey, just maybe the bolts on one of the main caps is loose (doubt it, but no reason you can't be an optimist). Likely you will need to put new mains in. You might need the crank turned.

 

[Prof]

Lots of good suggestions in this thread.

Just don't give up on it...maybe just pull the engine as it is and send it to Tony and have him rebuild it.

Heck he can probably get it back to you in a couple of weeks...well maybe a month...or two or...just how long has it been Eddie?

Seriously, a lot of us have rebuilt and never looked back!

 

[FastRam]

Reading your Post it seems you have tried the following checks but here's some service text to help diagnose valve train noise. Also for the compression test, minimum result should be 689kPa (100 psi) and values should not vary by more than 25% from cylinder to cylinder. If results indicate abnormally low values, perform the test again to validate the first set of readings. The second test will help also to pin point the problem cylinder(s).

HYDRAULIC TAPPET NOISE DIAGNOSIS
PRELIMINARY STEP TO CHECKING THE HYDRAULIC TAPPETS

Before disassembling any part of the engine to correct tappet noise, check engine oil level and oil pressure.

1. Check the engine oil level. Oil Level Check: stop engine after reaching normal operating temperature The oil level should never be above the FULL mark on dipstick, or below the ADD mark. Either of these two conditions could be responsible for noisy tappets. Allow 5 minutes to stabilize oil level, check dipstick.
2. Remove oil pressure sensor.
3. Install a reliable oil pressure gauge at oil pressure sensor location.

The oil pressure should be 206.8 - 551.6 kPa (30 - 80 psi) at 2000 rpm.

OIL LEVEL TOO HIGH
If oil level is above the FULL mark on dipstick, it is possible for the connecting rods to dip into the oil while engine is running and create foam. Foam in oil pan would be fed to the hydraulic tappets by the oil pump causing them to become soft and allow valves to seat noisily.

OIL LEVEL TOO LOW
Low oil level may allow pump to take in air which when fed to the tappets, causes them to become soft and allows valves to seat noisily. Any leaks on intake side of pump through which air can be drawn will create the same tappet action. Check the lubrication system from the intake strainer to the pump cover, including the relief valve retainer cap. When tappet noise is due to aeration, it may be intermittent or constant, and usually more than one tappet will be noisy. When oil level and leaks have been corrected, engine should be operated at fast idle to allow all of the air inside of the tappets to be bled out.

VALVE TRAIN NOISE DIAGNOSIS
To determine source of valve train noise, operate engine at idle with cylinder head covers removed and listen for source of the noise. NOTE: Worn valve guides or cocked springs are sometimes mistaken for noisy tappets. If such is the case, noise may be dampened by applying side thrust on the valve spring. If noise is not appreciably reduced, it can be assumed the noise is in the tappet. Inspect the rocker arm push rod sockets and push rod ends for wear. Valve tappet noise ranges from light noise to a heavy click. A light noise is usually caused by excessive leak-down around the unit plunger which will necessitate replacing the tappet, or by the plunger partially sticking in the tappet body cylinder. A heavy click is caused either by a tappet check valve not seating, or by foreign particles becoming wedged between the plunger and the tappet body causing the plunger to stick in the down position. This heavy click will be accompanied by excessive clearance between the valve stem and rocker arm as valve closes. In either case,
tappet assembly should be removed and replaced.

I hope this helps.

 

[WOT]

The easiest way to see if the noise is coming from a main bearing is to put the mechanic's stethoscope on the side of the oil pan or on the block immediately above the oil pan. The knocking sound will be fairly pronounced at those locations. Works every time.

I had 2 motors with bad mains (not viper motors). I hestitated to put the stethoscope on them for fear of confirmation that my motor would have to come out. With my hand shaking, I would start up the motor, warm it up, and then climb under. It sounded like the noise could be coming from anywhere. Then, as I pressed the little rod from the mechanic's stethoscope up to the bottom of the block, my worst fears were confirmed. The knock was the telltale sign of a bad main bearing, and the motor would have to be rebuilt. Sucks, but you have to do it.

 

[VENOMOUS1 RACING]

Help me help us think this one out!

GUYS!!! Noone has commented on the 4 cylinders other than them being low. I am not in front of my truck, but can someone tell me if those 4 cylinders happen to be firing from the same pack? I am thinking to check whether the new coil packs ( if he got them) are firing now. It seems that if driven for awhile on 6 supercharged cylinders you would have a negative effect. Ringwash = lower oil pressure and ringwashed oil will cause knock in a heartbeat as the gasoline cleans the oil off the bearings and piston rings and cause bottom knock and a lil piston slap. It only explains the lower pressure on those cylinders vs. the rest and had to have been happening for awhile. IF those cylinders weren't firing for say....60 miles and the gas continually injected into those cylinders washing the oil splashed on the pistons off each time it came round. That'd for sure wear the rings out in a likety split second.
I would personally drain the oil, smell it, look at it in the sunlight for metal, refill with correct oil. Ensure you are getting fire to those 4 cylinders. If it wasn't, could be a coil pack, a fuse, relay, ECM signal to coil pack for firing? Those 4 cylinders are to suspect as to the problem.

 

[WOT]

If there were 4 cylinders not firing for 60 miles., a code would be set for misfire, a code would be set by the O2 sensors for the ridiculously rich mixture, and if there are cats in place they would be glowing bright red, and the oil level would rise above the dipstick mark, and the truck would run like 6-cylinder -- it would feel slow as hell.

 

[71dusterjon]

before i parked it, it never felt slow or set a code. i'm going to try to get prices for gasket set, crank and rod bearings plus rings. My boss thinks the main bearings sound good but it could be rod bearings or even a piston pin.

If i can get some money, i'll try to pull the motor and fix what's needed. We dont have a bore scope so i don't know how the condition of the pistons.

Whats the easy way to pull these motors; where to put straps around? How much should i take off the engine (heads, intake, ...)

 

[VENOMOUS1 RACING]

If there were 4 cylinders not firing for 60 miles., a code would be set for misfire, a code would be set by the O2 sensors for the ridiculously rich mixture, and if there are cats in place they would be glowing bright red, and the oil level would rise above the dipstick mark, and the truck would run like 6-cylinder -- it would feel slow as hell.

I am not convinced of the first 2 things you said. I (think) I have a coil prob that bogs down on power and feels like 6 cylinders then goes away and pulls like a MOFO like nothing happened. Most of the time if I just crack the throttle a lil more it instantly goes back to normal. I've also let it do this for minutes to try and produce a code to help me find the culprit and it will not although obviously running like crap. The O2s won't set a code unless there is a fault in the heater or O2 itself. It will just send the info to the ECM that the bank is running lean and add more fuel which makes things worse. I do agree that the Cat should be glowing red though from the uinburned fuel it's burning.

 

[WOT]

I am not convinced of the first 2 things you said. I (think) I have a coil prob that bogs down on power and feels like 6 cylinders then goes away and pulls like a MOFO like nothing happened. Most of the time if I just crack the throttle a lil more it instantly goes back to normal. I've also let it do this for minutes to try and produce a code to help me find the culprit and it will not although obviously running like crap. The O2s won't set a code unless there is a fault in the heater or O2 itself. It will just send the info to the ECM that the bank is running lean and add more fuel which makes things worse. I do agree that the Cat should be glowing red though from the uinburned fuel it's burning.

It takes a lot of misfires before it sets a code, but it should do it if it misfires continuously. If you had an actual Dodge scan tool, you could read the misfire count live.

The O2's won't set a code, but the ECM will set a code if the O2 continuously reports a rich mixture. If 4 cylinders were misfiring, you would have 40% of your fuel going out the exhaust pipe. I would think that would be beyond the limits of short term and long term fuel trims and would set a code, but hey anything is possible.

Hmm, now that you mention it, a misfire does show up differently on some type of oxygen sensors: yes there is a ton of fuel going out the exhaust, but there is also the oxygen going out the exhaust since the misfire was due to a no-spark condition. I believe that most 4-wire sensors will actually see the unused oxygen in the exhaust stream and not see the extra fuel as being overly rich.

This is one of those cases where an O2 sensor probably does not behave well because there is excess oxygen in the exhaust stream (which makes it think the motor is lean), but there is also raw fuel in the exhaust stream which will dilute and mask some of the oxygen.

I know that if just one cylinder has it's wire pulled, the 02 sensor will only see the extra oxygen, and the extra fuel that is blown out the exhaust port is not enough to mask the oxygen so the sensor will show that the motor is running too lean on that side. I'm not sure how it will respond to 4 dead cylinders though. So for now, the jury is out on what it will actually do. But it is probably showing the motor to be lean, not rich.

 

[VENOMOUS1 RACING]

It takes a lot of misfires before it sets a code, but it should do it if it misfires continuously. If you had an actual Dodge scan tool, you could read the misfire count live.

The O2's won't set a code, but the ECM will set a code if the O2 continuously reports a rich mixture. If 4 cylinders were misfiring, you would have 40% of your fuel going out the exhaust pipe. I would think that would be beyond the limits of short term and long term fuel trims and would set a code, but hey anything is possible.

Hmm, now that you mention it, a misfire does show up differently on some type of oxygen sensors: yes there is a ton of fuel going out the exhaust, but there is also the oxygen going out the exhaust since the misfire was due to a no-spark condition. I believe that most 4-wire sensors will actually see the unused oxygen in the exhaust stream and not see the extra fuel as being overly rich.

Being that fuel is raw and unburned I'd think it'd just pass out the exhaust unknown to the ECM being as the O2 sensor reads only oxygen content of the exhaust. Even if the oxygen is coming out with fuel vapor or liquid it shouldn't have an effect on the oxygen measured and still report lean back to the ECM and dump gas like a MOFO.

This is one of those cases where an O2 sensor probably does not behave well because there is excess oxygen in the exhaust stream (which makes it think the motor is lean), but there is also raw fuel in the exhaust stream which will dilute and mask some of the oxygen.

I know that if just one cylinder has it's wire pulled, the 02 sensor will only see the extra oxygen, and the extra fuel that is blown out the exhaust port is not enough to mask the oxygen so the sensor will show that the motor is running too lean on that side. I'm not sure how it will respond to 4 dead cylinders though. So for now, the jury is out on what it will actually do. But it is probably showing the motor to be lean, not rich.

Being that fuel is raw and unburned I'd think it'd just pass out the exhaust unknown to the ECM being as the O2 sensor reads only oxygen content of the exhaust. Even if the oxygen is coming out with fuel vapor or liquid it shouldn't have an effect on the oxygen measured and still report lean back to the ECM and dump gas like a MOFO. Not sure if the fuel content would mask the oxygen content?:dontknow:

 

[FSTJACK]

I had an intermitant misfire on the silver truck when it was almost new.

It would drive the wide band O2 sensor on that side crazy, it would swing from lean to rich constantly.