Intermittent clacking sound

[Lawrence]

Hi fellows, there seems to be an intermittent loud clacking sound coming from my engine. It makes the sound once in a while. If i hear it today, i may not hear it for a couple weeks or longer. It makes the sound for about 5 seconds, during which time the engine also shakes, and then goes away. What could be the cause of this sound? Could it be bearings, or the fuel system?

[Robo]

Sound like sticking valve hitting piston.
turbo fins breaking up and being sucked back into cyl, and being crushed/hammered against head.
worst case scenario, not good.

[Lawrence]

Sound like sticking valve hitting piston.
turbo fins breaking up and being sucked back into cyl, and being crushed/hammered against head.
worst case scenario, not good.

Thanks Robo. No turbo (not yet). Would the sticking valves be sometimes or would it be constant?

[threedogs]

Could be staving for fuel every now and then,,, change the fuel filter and inspect, or,,,
Drop the oil and change it checking oil for metal contaminates,
That's all I have

[Lawrence]

Could be staving for fuel every now and then,,, change the fuel filter and inspect, or,,,
Drop the oil and change it checking oil for metal contaminates,
That's all I have

Thanks threedogs, will try both of those. Havent changed the fuel filter in quite a while.

[threedogs]

What motor and year is your Patrol ,helps with all the info.

[Col.T]

G'day Lawrie,
can only hope it's not Robo's prediction 'cause that would suck big time.
Are you absolutely certain the noise is coming from the engine rather than somewhere in/around/near the engine bay?
Does it happen at particular revs or speed? Under load or cruising easy? When it stops is there any noise/shudder and then all O.K.or does it just fade away? Could you stop when it happens and get your head under the bonnet, even with the dopey looking old trick of a long screwdriver on various parts of the donk and the other end in your ear to get a good idea of location? (By the way, it's best not to stick the sharp end in your ear).
Seems to me a bit unlikely that there's bits of metal banging around on pistons. Would have thought that sort of noise would stick around and have a very definite effect but I dunno as it's never happened to me.
Keep us informed
Col

[Lawrence]

Its a 1989 Y60 lwb wagon with the td42 engine. It comes suddenly and goes just as quickly as it came. I am not sure that it is coming from the engine, but it makes the vehicle shake a bit while it is there. And it doesnt seem to move with the revs. I wondered if it might be the vacuum pump on the alternator. I did have an mk that had that sound and I rebuilt the engine as it was the bearings, but that sound was constant and got louder with the revs.

[Robo]

Thanks Robo. No turbo (not yet). Would the sticking valves be sometimes or would it be constant?

Can be either.
I said worse case, ( hope it's not, fingers crossed Threedogs is on the money ).
otherwise you can take an pro-active approach and get someone qualified to take a look at it.
On the chance it's a valve you don't want that to continue to happen.
best of luck with it

[Col.T]

G'day again Lawrie.
guess by now it's either fixed or you're riding a push bike.
If neither, can you clarify the '...it doesn't seem to move with revs.'
There aren't many engine internals which don't change up/down with revs... Trans./drive train will vary with revs/gears... Suspension/wheels etc. with speed.
If it's ongoing, when it happens next, if manual, clutch in and rev it/idle it....... What do you do with auto? Maybe drop it a gear to get a rev change. Be useful to see if the noise varies with revs or not.
By the way, what do you do for 4X4 sport in the beautiful Carribean? Apart from drinking rum that is?
regards,
Col

[Lawrence]

G'day again Lawrie.
guess by now it's either fixed or you're riding a push bike.
If neither, can you clarify the '...it doesn't seem to move with revs.'
There aren't many engine internals which don't change up/down with revs... Trans./drive train will vary with revs/gears... Suspension/wheels etc. with speed.
If it's ongoing, when it happens next, if manual, clutch in and rev it/idle it....... What do you do with auto? Maybe drop it a gear to get a rev change. Be useful to see if the noise varies with revs or not.
By the way, what do you do for 4X4 sport in the beautiful Carribean? Apart from drinking rum that is?
regards,
Col

Engine running quite smoothly, As i said the sound happens once in a while. Been happening over a year now. it doesnt speed up with revs, but i might be mistaken there as it comes and goes so quickly.
We offroad here mostly in the mountains. Its not as big here as it is in the US and Australia as yet. Mostly farmers offroad at the moment, but it is building slowly mostly with jeeps and samurais. I havent been able to take mine offroad yet. I plan to do so later this year though. Drinking rum? I never touch the stuff, but the rum is great from what i understand :)

[threedogs]

Any up dates , interested in what caused the noise
For others the Samurai is a Suzuki I think

[philfree]

im just gona through this out their could it be from the fuel pump ive seen some sick trucks come through work (i work for a truck repair place) and their making all sorts of noises witch got traced back to fuel related eg not enough to the pump or the pump and i know someone with a gq td42 that he brought for a steal because when he went around a corner it would make clouds of smoke and funny noises and stall witch was a blocked orifice in the pump it's just a thought thats all

[Lawrence]

Any up dates , interested in what caused the noise
For others the Samurai is a Suzuki I think

None yet. and yes the Samurai preceded the Jimmy here.

[oncedisturbed]

And the Katana was our version of the sierra


Sent from my iPhone using Motorculture mobile app

[Col.T]

Hey there Lawrie,
reckon you've got the mother of all mystery sounds. Got us all stumped. Seems to have you as well.

By the way, I must say I also generally never touch rum or for that matter any of the other beverages myself, even if I've washed my hands first. Find it much simpler to work from bottle to glass to mouth to swallow. Eliminates all complications.

Just another thought. IF the prob. is not actually in the engine but for example in the transmission or wheel/suspension assembly, you may still feel something when it played up.
Can you put a place or time or road surface or speed or steering wheel angle or rev range etc. etc. on the effect?
Probably a toughie but it may point you in another direction.
Good luck,
Col

[Lawrence]

Hey there Lawrie,
reckon you've got the mother of all mystery sounds. Got us all stumped. Seems to have you as well.

By the way, I must say I also generally never touch rum or for that matter any of the other beverages myself, even if I've washed my hands first. Find it much simpler to work from bottle to glass to mouth to swallow. Eliminates all complications.

Just another thought. IF the prob. is not actually in the engine but for example in the transmission or wheel/suspension assembly, you may still feel something when it played up.
Can you put a place or time or road surface or speed or steering wheel angle or rev range etc. etc. on the effect?
Probably a toughie but it may point you in another direction.
Good luck,
Col

yes i will check that out, whenever i hear the sound again. It came on so suddenly and went, i cant remember the conditions, i know it has come at idle and also while driving.

[Col.T]

Lawrie,
nothing beats the 'intermittent' problem, does it. It's really the very very best isn't it.
How you nail it, nobody knows but you've just got to keep at it.
All the best
Col