Noisy engine.

[It's just a six]

Re: Noisy engine.

Rod knock sometimes only knocks when there is a load on the engine, like opening the throttle.

You should be able to hear the knock more when driving & opening up the throttle. The knock is load sensitive it seems.

 

[Quickstop [UK]]

Re: Noisy engine.

No it won't. Compression reading won't change if they don't open at all. Try it sometime.


A compression test might show if the valves aren't closing all the way, but has nothing to do with opening.

I stand corrected.

Any other ways to diagnose or detect a collapsed lifter?

 

[DaveP]

Re: Noisy engine.

......................

 

[ty166]

Re: Noisy engine.

Rod bearings....... cut open the filter.....

 

[jusssi]

Re: Noisy engine.

Thanks for responses. Engine runs pretty well, idles good higher rpms no rattling. Noise is dependent to load like when open throttle. I know it's not easy to analyze from phone recorded video.

Rod knock sometimes only knocks when there is a load
on the engine, like opening the throttle.

You should be able to hear the knock more when driving & opening up the throttle. The knock is load sensitive it seems.

Rod bearings....... cut open the filter.....

This is what I'm gonna do next.

 

[Eric Fischer]

Re: Noisy engine.

My engine makes EXACTLY the same noise. So hopefully we can all work together to figure this out. Is your bottom end stock? Does the noise get better when hot? Is yours a balance shaft motor?

My short block is a balance shaft block with JE forged pistons. I always thought mine was due to piston slap.

 

[drturbo69]

Re: Noisy engine.

My engine makes EXACTLY the same noise. So hopefully we can all work together to figure this out. Is your bottom end stock? Does the noise get better when hot? Is yours a balance shaft motor?

My short block is a balance shaft block with JE forged pistons. I always thought mine was due to piston slap.

sounds like upper cylinder to me-piston slap or wrist pin.Forged pistons?

 

[jusssi]

Re: Noisy engine.

Some update here. I took engine from truck and rod caps off. Saw some copper on couple bearings and metal in pan. I swept finger in pan and feel grains in oil.
Bearings didn't seem wery bad so is this my problem or could there be something more what to check when engine is open?

 

[jusssi]

Re: Noisy engine.

Pulled crank and check mains, all ok. Pistons and cylinders good, no play on wrist pins. Only some wear on rod bearings, but not much that causes this noise, though.
Crank is in .010 undersize.

 

[Eric Fischer]

Re: Noisy engine.

Pulled crank and check mains, all ok. Pistons and cylinders good, no play on wrist pins. Only some wear on rod bearings, but not much that causes this noise, though.
Crank is in .010 undersize.

My guess is still that it is piston slap. With the pistons at TDC, did you measure how much they rock in the bores?

 

[Damian]

Re: Noisy engine.

Some update here. I took engine from truck and rod caps off. Saw some copper on couple bearings and metal in pan. I swept finger in pan and feel grains in oil.
Bearings didn't seem wery bad so is this my problem or could there be something more what to check when engine is open?

It doesn't take much for them to make noise, is say that is the likely culprit. I'd have the crank machined and replace all of the bearings and the rear main seal.

 

[IGottaSy]

Re: Noisy engine.

Any other ways to diagnose or detect a collapsed lifter?

Most obvious indication of this is the difference in lift to adjacent push rods. I saw it once on a wiped cam lobe in a Grand National I used to own. Effect is similar for collapsed lifter.
I would measure that lift with engine running but it's gonna be messy.

 

[It's just a six]

Re: Noisy engine.

Some update here. I took engine from truck and rod caps off. Saw some copper on couple bearings and metal in pan. I swept finger in pan and feel grains in oil.
Bearings didn't seem wery bad so is this my problem or could there be something more what to check when engine is open?

Grains in the oil does not sound good, especially if you can feel the grains.

Were the rods bearings snug in there places? Or did they fall out easy?

 

[jusssi]

Re: Noisy engine.

Thanks for responses. I didn't notice anythin unusual when took rod caps off.
I thin I'll disassemble entire engine and check out all, incl. crank, rods, pistons cylinders... etc. So I can be sure for it.

 

[Eric Fischer]

Re: Noisy engine.

Thanks for responses. I didn't notice anythin unusual when took rod caps off.
I thin I'll disassemble entire engine and check out all, incl. crank, rods, pistons cylinders... etc. So I can be sure for it.

Before disassembling the engine, I would measure the piston rock. Follow this procedure and let us know if your pistons have excessive rock. That would explain why your engine seems to have what sounds to me like excessive piston slap (which is a result of pistons too small for the bore).

The best way to measure a non flat top piston is, after zeroing your indicator, to set your indicator on the flat or quench part of the piston, rock it all the way to one skirt or side, record the measurement. Rock the piston against the other skirt & record the measurement.
Divide the total of these numbers by two & that is as close to what your piston to deck height will be.
Do it a few times & you will get a "feel" for when the piston is "rocked" over all the way
If you have a flat top piston then you can use the center of the piston.

 

[jusssi]

Re: Noisy engine.

Ok, Now I've made some research wit hthis. I'm pretty sure that it's pistons. Pistons felt loose in cylinders, I took them out and measured bores, all ok. Bores are in good shape; can see honing grooves except area where skirt meets cylinder. Pistons are good too, except some wear at skirt, not much, but still.
Pistons are JE extreme duty which are requiring more wall clearance than stock or some forged.
Is there way to increase cylinder wall lubrication? Or how about piston skirt coating?

 

[Damian]

Re: Noisy engine.

I have the same pistons and I just accept the fact that they are loud. I pulled the heads off not long ago and the cylinders still look great. I wouldn't worry about it too much.

 

[Jkanser]

Re: Noisy engine.

JE's are known for piston slap. Had them in a DSM I built many years ago and got rid of them after growing tired of the noise and tuning issues it causes.

 

[Damian]

Re: Noisy engine.

Once my engine warms up, it quiets down quite a bit.

 

[Eric Fischer]

Re: Noisy engine.

JE's are known for piston slap. Had them in a DSM I built many years ago and got rid of them after growing tired of the noise and tuning issues it causes.

I had reported earlier in this thread that my motor is just as noisy as the OP's. Not surprisingly, I am using the same exact pistons as him. It sounds like a diesel on startup but as Damain stated, it gets better when it warms ups.