On my way to a job interview today my car started making an unwanted noise (ended up parking the car on double yellows and running to my interview ). Ended up coming home on a breakdown wagon
The noise is similar to the noise I heard when the crankshaft cracked on the old engine, that time the noise was constant when the engine was running. This time it only occurs when the engine has warmed up and I rev the engine. Sounds more like a tapping than a banging from the bottom end though this time.
I have no luck
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The guy started asking hours I'd like to work so I think so
Five minutes before the noise started I was traveling down the by-pass at about 50 and the oil pressure was sitting around 50 as well. No smoke at all.
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Hope you have better luck than my brother. He had the same symptoms in his Spitfire on Friday. Stange thing was, when we started it next morning, after an initial rattle, it ran sweet as a nut, no tapping. When we took the head off though, the no 1 bigend had about 2mm drop! Still can't understand how it ran so quiet immediately before the stripdown!
Thick cold oil!
No - head gasket won't cause bottom end rattle - it makes the whole engine rattle! If you really think it's bottom end - then off with it's sump for a look see. But if it had 50 psi oil.......
The car felt like it still wanted to go when it got going - although when the clutch was in it cut out - it sounded like there was something loose in the engine that rattled the more the car revved.
Last edited by MColes on Wed Oct 28, 2009 10:52 pm, edited 1 time in total.
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If the oil pressure & coolant levels are still OK (and oil & water haven't mixed) could you let the engine warm up then look for the noise. Try simple things first, loose bolts, radiator fan touching something, water pump. Obviously be very careful around a running engine don't get snagged in the fan or pulleys.
Unless you are really sure it is the bottom end I would take off the rocker cover and make sure nothing is loose or broken.
While I was waiting for the recovery guy - in my best suit I might add - I took the rocker cover off and made sure the tappets were tight and hadn't worked loose as I adjusted them recently. They were fine. Will take a proper look on Friday or Saturday (got uni tomorrow and it will be dark by the time I get home )
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I had a very similar problem a few years ago, very loud rattling on acceleration. Thought it might have been a big end bearing gone, but as BM suggests, turned out to be a blown head gasket and a crack in the head between two of the chambers
MColes wrote:On my way to a job interview today my car started making an unwanted noise (ended up parking the car on double yellows and running to my interview )
MColes wrote: This time it only occurs when the engine has warmed up and I rev the engine. Sounds more like a tapping than a banging from the bottom end though this time.
Are you sure it isn't the timing? If my moggie is too far advanced, it makes all sorts of unpleasant noises when I rev it.
Head gasket gone between 2 and 3 can sound uncannily like a shot big end.
Replaced one on the MOT that sounded like bottom end damage.
What a relief that was
Matt,
Try the manifold nuts too. If they're not tight its possible for an exhaust pulse to push the manifold just enough and "fire" thro' the gap and produce a noise just like a duff big end. As I found out after pulling the sump, findind all the BEs OK, etc. It clatters in time with the engine speed and, of course, is much worse the wider the throttle opening.
Either way, the best of luck, MikeN.
Morris Minor, the car of the future. One day they will all look like this!
). Ended up coming home on a breakdown wagon 
