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MG MGF Technical - What's the story with lifters ?

Hey All,

Sorry for the second post in just a few hours. My MG-F is in the workshop right now and I'm getting some major problems via my mechanic - apparently.

Anyway, I have found out what the strange "click clikc" noise was. Apparently it's the lifters not working too well and they need replacing. Gonna cost me a packet. What's their purpose and what's the problem if they fail ? I was told all 16 need replacing. Is that normal ?

Excuse my ignorance - but what exacty does this mean ?

At the same time I'm getting the timing belt replaced and also the psark plugs. It's done 82,000 km and thought it was time to do a decent service.

Apologies for the additional post. I'm just very car ignorant.

Thanks

Sonny


Sonny Foster

Hey, Sonny, no apologies,,, please.

Thats what this forum is for. To get help and to help others. :-)

The hyraulic valve lifters also known as lash adjusters or cam followers, keep the camshaft lobes in contact with the top engine valves.
There are solid ones and hydraulic ones.
Not sure what you have in yours.

Engines used to use push rods and the tappitts could be adjusted.....Agggh those were the days.

The ticking you hear is the valve lifters not being able to keep that gap small enough or fast enough. In otherwords they lag in closing the gap.

This lag can be caused by several things.

1: Oil is too thick. ie wrong type/viscosity egs 30W50, so it does not flow easily enough into the lifters.

2: Oil is too thin and so the lifters click because the oil flows out too quickly. egs 5W30

3: Lifters are worn. A spring and ball are in them which can go bung or sides of lifters are qworn as well so thers slack in the guides.

4: Lifters are clogged. A build up of oil deposits, gunk, dirt etc due to an ineffient oil filter.
I have cleaned them out in the past, with good success but not guaranteed.

Here is a link if you want to learn more about "How Stuff Works"

http://auto.howstuffworks.com/engine.htm

And yes if some lifters are gone, chances are very soon others will go, so since the camshafts are out, all lifters should be repalced. Not cheap. :-(
But, you don't want to do the job again soon because of another lifter going bung in the near future.

Cheers.
Branko.
Branko

Usually the reason they replae all 16 is because it is very difficult to work out which one or two are faulty.

It is usual to try a flushing oil and then normal oil at motorway speeds to see if that clears them up (it often does). VVC engines are known to be 'tappety'
Will

If you are lifing the camshaft out it might be worth replacing them with some hotter cams. :-)
Steve Ratledge

Steve, forgot to tell you the part number on the '135 cams I have - it was the same number as on yours: LGC100300

Sonny, sometimes a good oil system flush will restore the normal operation of the hydraulic tappets (see Branko's explanation number #4) - which is a good idea anyway even if you still end up having to replace the tappets.
Rob Bell

You can determine which lifter it is (or there abouts) before you take off the rocker cover.
(or should we now call it "lifter cover" ? LOL)

Use a mechanics stethascope and locate the tapping.
These are cheap to buy ($18Aus) and are very useful in other things, like tracking down any engine noise.
Great for bearing noise diagnosis as well, and you look "professional" in doing it.

Alternatively you can use a long screw driver and place the handle end to your ear and place the pointed end to the engine. Just be careful if near moving parts and if you have long hair, as you don't want a screwdriver in your ear! and become scalped in one foul swoop. :-(

cheers.
Branko.
Branko

Further to what Branko/Rob says, back in the dim and distant 80s, I had a XR2, with the usual Ford CVH engine problem of leaking valve stem oil seals, and noisy lifters.
when I took it in to the garage for the oil seals, the Mechanic also did the screwdriver test, to find which lifters were noisy, removed them,then a good spray with release oil and several blows with a rubber mallet, re-fitted and presto " no noise!".

Poor quality oil, of lack of oil changes causing them to "Gum" up, seemed to be the problem.
Mark.L

"4: Lifters are clogged. A build up of oil deposits, gunk, dirt etc due to an ineffient oil filter."
sound good advice , they can be popped apart and cleaned with success check for carbon deposits inside. Regular oil changes(5-6k) help rather than the 12-15k that seem to be recommended these days.
Mike.
mike

This thread was discussed on 03/03/2005

MG MGF Technical index

This thread is from the archive. The Live MG MGF Technical BBS is active now.