Engine Damage

[ardiesse]

You wrote -

"on the bearing is - 001 - HOLDEN - FR5 RM500 any idea what this is indicating?"

It means your motor has not been rebuilt, and still has its factory bearings (and pistons and rings, judging on the piston size). The crankpin diameter at the factory was at the low limit of tolerance, and so a 0.001" undersize bearing was fitted to achieve specs.

Rob

[Harv]

Oh, and - you can estimate the wear in the cylinder bore with a piston ring and feeler gauges.

Clean the carbon off the top of the bore. Insert a comparatively unworn ring completely, but squarely, just inside the top of the bore. Measure the ring gap. Push the ring squarely down into the bore so it sits just below the ring ridge. Measure the gap again. Subtract first measurement from second measurement, then divide by 3.

So let's say you measure 0.040" gap first and 0.063" gap next. 63 - 40 is 23, divided by 3 is 0.008" approx.

The Last Daughter is doing geometry at school, and was asking for examples of where she could use "circumference = pi x diameter" in real life. Working out bore wear in a grey is a pretty good example

Cheers,
Harv

[59wagon]

The Last Daughter is doing geometry at school, and was asking for examples of where she could use "circumference = pi x diameter" in real life. Working out bore wear in a grey is a pretty good example

Cheers,
Harv

Hahaha. I’ve often done similar with my kids Harv - mind you, I remember asking my teachers the same thing “Why do I need to know that?” If only I knew then what I know now, I would’ve paid more attention back then!

Cheers,

John

[Patrick_R]

I have been reading this with interest.

I now have a headache thinking as to what that large offending piece is.
How this happened & what it is is a real mystery.

I’m looking forward to seeing this go back together with just a clean up.

I’m sure she will run good as new.

Ric.

[RobinGi]

Update …
good news and bad-

Got the engine back together and started up - all fine adjusted tappets and checked timing, sounds good has a mild cam so it was burbling along quite nicely.

went for a drive and same as last time it started knocking after about 5 min, having trouble deciding what the knock is this time, it doesn't seem to change freq much as the rev's go up/down but most prominent with the motor under load and cant hear it if cruising along at 60K's on the flat. thought it might be something hitting with the engine vibrations, double checked every thing I can think of.

got underneath and noticed the clutch slave cyl bolt was too long and wasn't tightened against the cyl so i swapped out for the correct length and fitted return spring also oil filter was very close to steering shaft (rack/pinion fitted) now the knock is more of a rattle.

put the rear wheels up on stands and ran the engine up and down through all the gears and could not reproduce the noise, same as in neutral revving the 202 it sounds great.

tried advancing the timing to see if its pre ignition and didn't notice any change.

but a good point it seems to have a bit more oomph in the top end so gotta be happy with that.

[Errol62]

Good the engine seems okay. I wonder if the bell housing or exhaust is a bit close to the floor somewhere.


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[FJWALLY]

was thinking same - perhaps under load part of engine or suspension/steering coming into contact somewhere - had a 4x4 once that the exhaust was touching only in 4x4 low when the peddle really buried - sounded like the diff was about to fall off but for the life of me could not replicate it any other time - was only when we changed the exhaust we found the marks

Good the engine seems okay. I wonder if the bell housing or exhaust is a bit close to the floor somewhere.


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[RobinGi]

To me it sounds like one of the main bearings but the problem is the knock sounds different every time I change something

Got a mate to jump in the passengers to have a listen and see if he can detect where he thinks its coming from as with my hearing I have trouble with sound direction, and instantly the knock went away, drove up hill down hill fast & slow acceleration and not a squeak !

So to my thinking its lends itself to something knocking on the body, so driving home by myself all was good until I started driving up an incline and the knock came back with avengeance to the point that I had to take an alternate route on flat roads to get home with bit of a clatter all the way.

Once home I checked all round the engine bay for clearances and couldn't see anywhere where the motor/G box/exhaust could be hitting but couldn't see anything that came close.

While under the hood I adjusted the idle and air/fuel mix to get the idle a bit better and got a light knocking noise coming from the engine like a loose rocker/tappet noise, removed rocker cover and rechecked settings and all is good there, so I'm leaning toward pre ignition again so for an experiment I'm going to change the head over and see what difference that makes.

[ardiesse]

Rob,

Main bearing noise is a very deep-sounding grumbly, thudding sound, most apparent at about 40 mph in top gear on very light throttle openings. When the engine's under load, the noise is less; when the engine's under no load, the main bearings make no noise; but if you gradually lift off the throttle and then back on again lightly, you can make the sound come and go at will. Main bearing noise also appears each time you change gears, like a very short burst of machine-gun fire just as you go to disengage the clutch. When your main bearings are worn out to the point of making noise, you get oil leaks at the rear main bearing oil seal and the timing case, free of charge.

I've never yet come across a red motor with rattly mains. So I don't think you have main bearing troubles.

And please don't pull your head off again. It will gain you nothing. Does your engine ping? (by the way, pre-ignition is made worse when you advance the timing.)

It sounds to me like your exhaust system is hitting the underbody as the engine "winds up" on its mounts under power. I had a X2 which did this all the time. You need more than a hand's thickness of clearance between the exhaust and the body everywhere. I'd be inclined to look around the rear axle too. The fact that the noise went away when you had a passenger is significant. Repeat the "passenger test" a few times. Even put a 100 kg load in the on the passenger's side to double-check. It's possible that something's fouling the suspension.

What gearbox do you have, out of curiosity, and what type of exhaust system do you have? Standard manifolds/cast headers/extractors?

Rob

[Mick Jagger]

re first pic
looks like part of o out of Holden badge?
maybe to small

[RobinGi]

Update...
couldn't get a method to make the noise consistent, and the noise would change one moment I would swear bearings then next time flywheel scraping on bellhousing or just a rattle.

setup is 202 with extractors standard Stromberg carb, Toyota 5 speed gearbox, HR disk brake front end with R/P steering at the rear, plenty of room around the exhaust and g/box.

So I replaced the head ( mate can shave head to remove most of damage(cheap)) and of course after that the noise changed from deep thunk to more of a tick tick tick, mounted a go pro in the bay to see if anything moving around but all looked good.

So I ended up pulling out the motor and rechecking the bearing tension in case in missed something, now i found the starter lower bolt was only tightened up hand tight, everything else checked out normal but on reassemble I noticed the all the flywheel bolts were shaved down on the outer edge then inspecting the clutch plate I could see the springs had worn down on the facing surface, thinking about it the clutch plate is clamped to the flywheel while driving along so it couldn't be the offending rattle, I had replaced the clutch plate a while back and looking at the old plate is had suffered from the same problem (has more damage to the springs)



Reassembled and now the noise is gone, best guess is the starter motor was rattling around.
the only other change I made was the engine mount on the drivers side has 2 holes drilled into it to change the height of the motor position by about 15mm so this time I put it on the lower position to give more room to get the bell housing <-> engine bolts back in as their difficult to get too and can only turn I notch on the ring spanner on each movement.

[Errol62]

Something simple as usual, and therefore easily overlooked.


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[ardiesse]

Rob,

Damaged flywheel bolts means the clutch driven plate got installed backwards at some stage?
(I have done this myself, to my great embarrassment . . . )

Rob

[RobinGi]

Clutch plate can only go on one way, the springs are biased to one side so if its on the wrong way you cant bolt up the pressure plate.

[EK283]

I have done the clutch plate the wrong way around as well. It is possible and the damage is exactly the same.

After a few goes it wears the bolts and springs down and the noise becomes less harsh.

It also depends how offset the clutch plate springs are but definitely possible.

Regards Greg