Noise at idle (1 Viewer)

[Hodgy]

Hi everyone, bit of a problem for you all......

We have a HZJ75 here in the lodge which is making a noise at idle.

The noise is a deep, harsh sounding hollow rattle, louder underneath than above the engine and seeming to come from the sump or the bellhousing. It's there at idle and still there when I raise the revs a little but can't be heard above about 1000rpm....whether this is due to louder engine note or because the noise goes I don't know. It's undriveable at the moment as the rear springs are off so that course of diagnosis is unfortunately out.

I've changed the clutch throw out (release) bearing and the pilot bearing for new ones as these were the first parts suspected.

I've run the engine with no ancilliary belts, so it's not the water pump, AC pump or alternator. I removed the vacuum pump and ran the engine, noise still there.

While the clutch was apart I checked the flywheel bolt torques ( - all fine) and inspected the flywheel itself ( - also fine).

Depressing the clutch makes no difference, selecting gears with the clutch in also makes no difference.

The timing belt and tensioner are fine and the injector pump has recently been reconditioned....no obvious change in noise when resting a screwdriver on each injector pipe in turn.....

I've had the sump off today and checked the crankshaft end-float with a lever, tiniest, tiniest bit of movement, only noticable due to the oil between the faces sticking and unsticking. Checked all the connecting-rod bolts and the main bearing carrier bolts for tightness - all fine. Levered, pulled, wiggled and otherwise made move every big end, all seem ok, tiny bit of lateral movement - sliding on the crankshaft - but no looseness sideways or up and down. Little ends similar.

I've just about had enough of the thing to be honest!!


The things I ain't checked yet are the PAS pump (will try to run the engine with it removed) and I want to remove the gearbox again and make the engine run without it fitted to completely isolate the engine.


If anyone has any ideas, please....let me know....




Before I set it on fire....


Joe

 

[Cruiser70]

mmm you might not like it.
Big end Bearings?
YouTube - Big End Failure

YouTube - 205 gti 1.9 engine problem big end bearings?
Have a listen...sound the same?
If so do not run it anymore, whip the sump off and take the sump off and remove one of the bearing caps and have a look, you will need a huge breaker bar to remove the caps, specially if you are a weakling like me, its easy enough, I dont know the HZJ75 engine, so i could be wrong
They usually go at one end first nearer the clutch housing if I remember could be just some new shells a cheap fix, if crank is scored then it will probably be a strip down gulp.
Of course do the obvious things first, although it should only take an hour or so to check, providing you can the sump off.
Remember to do the bolts back up like you undone them, when my old motor was checked we needed a 2ft breaker bar with a 3ft pipe on the end to get enough leverage!
whats the oil pressure like?

Martin.

 

[Cruiser70]

Doh, I should read more before posting.
Still you could whip a cap off and have a look at a shell or two...

 

[inkpot]

Howdy! Had a similar sound once on an old Chevy V8. Long story short, the top of the flywheel dust cover had gotten bent just enough up near the rear main seal on the engine, that the ends of the flywheel bolts that go thru the crankshaft were rubbing on it. Thoght I had ruined an engine, but a 5 minute fix to bend it out took care of it. Good Luck. John

 

[Radd Cruisers]

Check your BEBs by taking them out and inspecting.

The other source of a deep, harsh, hollow rattle can be piston issues - cracked piston, broken rings/rings lands going (often isn't too noisy until it's bad), wrist pin area coming apart.

~John

 

[Hodgy]

Thanks guys, I dropped the sump and got the head off yesterday.

Had a look at the shells...hopefully 1, 2 and 3 should be attached here...

 

[Hodgy]

.... and 4, 5 and 6 here.

The upper shells are slightly scored on some, but mainly 5 and 6. All the upper shells are worn smoother in the 11 and 1 o clock positions.

Could that slight scoring make the noise I've been hearing??

Crank is smooth with no scoring on all big-end journals.

 

[Hodgy]

Also found this in the oilway at the rear of the head, any ideas what it is??

Thanks

Joe

 

[Aussie 25]

Hi Joe, that little thing is the oil restrictor it goes in the oil hole at the bach of the block. Just an odd sugestion the harmonic balincer hasent come loose and floged out the keyway?. Ian.