M271 - Rattly tappets ???

Remmoc

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More issues although im not unduly worried as such . I think ive got a rattly tappet or two . When its cold its quite bad but once warmed up after a few miles its gets much better although still audible .

Its NOT the chain as it rhythmic and rises and fall with engine revs , very much a rapid tap tap tap sound .
Cam magnets were changed 6 months ago , oil is 5W 40 Merc spec and that was changed in September.
Is it OK to just keep driving the thing ???

No codes on the engine at all at present and its running fine .

I guess its a huge job to sort

Engine is the Pile of rubbish known as the M271
 

Petrol Pete

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If you are convinced it's not the chain/sprockets then just drive on .Happy motoring :thumb: But this engine is known for destroying itself due to timing chain/sprocket wear, usually preceded by a warning rattling sound on cold start up. Yours seems to have all the symptoms, what makes you say it is not the timing chain ?
 
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Remmoc

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I get a 1/2 second slight rattle on start up - apparently this is normal when the cars been stood a while - i still get this but now its followed by the rapid tap tap tap sound which ive had before on other engines , it gets quieter as you drive and after a few miles its gone . I cant justify spending anymore on this car - i seem to have a bad one as just last week the starter motor failed.
All joking aside but from what ive read these engines are by all accounts a bit rubbish . Only 128,000 miles , being a Merc id expect something far better . My Hillman imps on 400,000 miles and still runs fine
 
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E55BOF

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You say: "...after a few miles its gets much better although still audible" and "...after a few miles its gone". Which is it?

If the well-known timing gear problem is raising its ugly head, does that give a regular rattle that quietens down after the engine warms up? I don't know, but somebody will. On most other engines, it could well be just a 'lazy' cam follower.
 
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Remmoc

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You say: "...after a few miles its gets much better although still audible" and "...after a few miles its gone". Which is it?

If the well-known timing gear problem is raising its ugly head, does that give a regular rattle that quietens down after the engine warms up? I don't know, but somebody will. On most other engines, it could well be just a 'lazy' cam follower.
My bad , 2 miles still audible , once fully warmed up around 4 or 5 miles its silent
 

E55BOF

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If it wasn't an M271, I'd suspect a lazy cam follower. Somebody will be along soon to tell us whether your symptoms fit the timing gear problem; there's a lot of knowledge on this forum, and we're pretty helpful too.
 

markjay

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Unfortunately the only way to know for sure is by removing the cam cover. And if you are not able to do this DIY, you'll need to pay a garage for the inspection.

You could try Wynn's Hydraulic Valve Lifter Treatment , I doubt it will help, but for the price (under a tenner) it must be worth a shot.

The other alternative is WBAC - my experience is that they check for stone chips and kurbed alloys with a magnifying glass, but do not care much about anything mechanical in the car, i.e. as long as it gets into their car park on its own steam they'll take it .
 
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Remmoc

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Update , poured some Wynns hydro valve cleaner in it , fired it up , it rattled for 2 seconds then went completely silent so if nout else it proves its a lifter , the silence is lovely BTW :)
 

Gazwould

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Wynns hydro valve cleaner .

You mean ,

268607


?
 

Gazwould

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Actually different or marketing ?
 
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Remmoc

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Says leave in , anyway the rattles still there below 2,500 RPM although it is quieter , after 2,500RPM it shuts up . not sure what to do now but i think il just drive it til it grenades itself then scrap it off
 

E55BOF

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The rattle may well continue to diminish as you drive the car, as the more stubborn deposits are removed. I'd do exactly what you intend - just drive it and see how you get on.
 

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