On Wed, 29 Nov 1995, Denise Thorpe wrote:
> > I posted earlier about what I thought was bearing noise. "Tock tock tock
> > tock tock" once per second. I just tried using a mechanic's stethoscope
> > to pinpoint the location of the noise. No luck. Either I haven't found
> > the right spot or a sound from deep inside is just hard to locate. Any
> > ideas?
> >
> > Otherwise I'll try to drop the pan tonight and have a look at the
> > bearings. What should I expect them to look like? If they look bad is
> > there a marking to tell if the bearing shells are other than standard
> > size? Or should I try to get a micrometer and measure? Or just order the
> > standard set, get some plastigauge, and pray that everything will be
> > alright?
>
> Arrgh... Don't drop the pan until you've eliminated the other
> possibilities. A rod knock goes knack-a knack-a knack-a; it's a two
> part sound. Lots of other stuff goes tock tock tock. It could even
> be your water pump or generator. Try listening to other parts of
Nope. I thought of that too. Took the fan belt off so the water pump
and dynamo and fan were out of commission: noise was the same.
> your engine and if it still sounds like it's coming from inside the
> engine, adjust the valves. If you've got a bad cam lobe or lifter,
> excessive valve lash (too much clearance) will tell you.
Valves are adjusted to spec and tick quietly. I'm not sure I understand
your last sentence. How do I tell if I have a bad cam or lifter?
It does sound like it's from inside the engine, not in the rocker area,
so I thought I had it narrowed down to rod or main bearings. A friend at
work listened to it and said it sounded like rod bearings. What do worn
main bearings sound like? Cam bearings?
> In answer to your question, you measure the crankshaft to find the
> size of the bearings. However, replacing the bearings requires that
> the head be off, too. If it turns out to be the cam or lifters, the
> cam, and therefore the lifters, can be replaced with the head on, the
> pan on and the engine in the car. Once you find out what's making
> the noise, tell the list so we can tell you how to fix it. Good luck!
>
> Denise Thorpe
> thorpe@kegs.saic.com
Thanks for the help, advice, and patience.
Kevin Sullivan -- sick MGA 1600 :(
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