Discussion
What are the tell tell signs of a loose liner? I have a 500 engine which has a rattle when I lift off the throttle and let the revs decay back to idle. For example, if I rev the engine to 3.5k rpm and then lift off the rattle starts at about 3k rpm and sounds like a shaken bag of marbles until 1k rpm and then disappears at the idle of 900rpm. It only happens when the engine is hot which makes me think it’s possible a liner! Any thoughts?
Thanks for the reply. I'm not aware of coolant loss but will keep an eye on that and also no over heating. Must be something else. I was thinking of removing individual plug leads while its ticking over to see if its cylinder specific. Could be a little end or would that rattle at all rpm?
lancelin said:
Thinking about this, removing plug leads while engine is running could be VERY dangerous - is there a best method or not?
Is not the best idea with coil packs Owen so leave the leads on the plugs, but you could safely and temporarily kill the fuel cylinder by cylinder by disconnecting one injector at a time at its electrical connector.Personally I wouldn't bother though as it's not going to tell you much, little end issues normally show themselves up on the overrun so this is one potential theory, but I could give you 5 such theories, these of course all remain theory and speculation until you commit yourself to an engine strip and inspection.
And if you're using the services of a professional to strip and inspect, don't be surprised if you very quickly find yourself involved in a full rebuild, I know its not what you want to hear but the truth is tearing down the engine, or at least the top end in the first instance is the only definitive way of seeking out the true cause of your engine noise and finally eliminating the issue.
I was always taught the engine will tell you if the situation is something you should really worry about:
1. Horrific noises that make you cringe = Very serious, don't drive it, strip the engine and inspect immediately
2. Intermittent and sometimes hard to discern mild noises = Probably nothing to worry about in the immediate, drive and enjoy, if it starts to gets worse investigate further
I know the above seems like an over simplification, but the occasional light tick and rattle while not ideal isn't usually something significant that demands immediate attention, just keep an ear open for it getting worse and try to enjoy the car.
In summary and being completely honest with yourself, which of the above two best describes your situation?
When it happened on my Chimaera 450 the symptoms were like very loud tappet noise but from deeper in the engine and only occurring intermittently. What was happening was that the liners on two cylinders temporarily attached themselves to the piston rings. They then moved with the pistons slamming into the cylinder head causing the loud noise. The cause of the temporary attachment was engine temperature related. When the engine temp dropped the liners unattached themselves and the noise stopped. There was no loss of power at all and the car drove perfectly normally. The temperature gauge showed the normal running temperature and there was no loss of oil or coolant. The answer was to have the engine rebuilt using flanged or "top hat" liners. Mine was done by V8 Developments and a very good job they made of it too.
Good luck with your engine. I am told it's not the easiest thing to diagnose.
Good luck with your engine. I am told it's not the easiest thing to diagnose.
Dont think that the other engine capacities can not be affected with this issue its just that the 5.0 is stressing out pistons that are shortened 
so we hear more feedback from these 
waiting for customers so thought I would post up this paper weight a 4.6 high miler if the steel pin as this wear ridge (you can see the impression/wear in the pic) you can imagine that the piston pin bores have also taken a kicking too 
not the greatest design to be frank far better to have bushed con rods & fully floating small ends I consider the factory RV8 method crude but its all a compromise at the end of the day I suppose 
Must get some O'Keeffe's on those hands
so we hear more feedback from these waiting for customers so thought I would post up this paper weight a 4.6 high miler if the steel pin as this wear ridge (you can see the impression/wear in the pic) you can imagine that the piston pin bores have also taken a kicking too not the greatest design to be frank far better to have bushed con rods & fully floating small ends I consider the factory RV8 method crude but its all a compromise at the end of the day I suppose Must get some O'Keeffe's on those hands lancelin said:
Would like to know?
Cheers
Found it Cheers
https://www.pistonheads.com/gassing/topic.asp?h=0&...
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