The dreaded Rover V8 500 engine rattle
Discussion
I’d really appreciate peoples thoughts on the best solution to rectifying the dreaded engine tick/rattle that has plagued so many Rover V8 500 engines. The problem is described in the post below but it’s not conclusive after 8 pages of discussion:
https://www.pistonheads.com/gassing/topic.asp?h=0&...
To summarise, the rattle starts when you lift off the throttle and let the revs decay from anything above 2000rpm to 1000rpm but it disappears at idle. The rattle is not present when the engine is warming up from cold or under acceleration. It sounds like a shaken bag of marbles! Most folk are suggesting it’s to do with the pistons and little ends.
I had my engine rebuilt over a year ago but they decided to keep the old pistons and little ends as they appeared to be in perfect condition!!! The piston rings were obviously replaced. The odd thing is the engine didn't make the noise pre rebuild! I noticed the engine made this noise soon after the rebuild but they said it was probably the upgraded fuel injectors! but the noise is getting slowly worse and its annoying!
Has anyone really found the root cause and what’s the most cost effective way of fixing it? Has anyone fixed it by replacing just the pistons and little ends? What stops it happening again?
https://www.pistonheads.com/gassing/topic.asp?h=0&...
To summarise, the rattle starts when you lift off the throttle and let the revs decay from anything above 2000rpm to 1000rpm but it disappears at idle. The rattle is not present when the engine is warming up from cold or under acceleration. It sounds like a shaken bag of marbles! Most folk are suggesting it’s to do with the pistons and little ends.
I had my engine rebuilt over a year ago but they decided to keep the old pistons and little ends as they appeared to be in perfect condition!!! The piston rings were obviously replaced. The odd thing is the engine didn't make the noise pre rebuild! I noticed the engine made this noise soon after the rebuild but they said it was probably the upgraded fuel injectors! but the noise is getting slowly worse and its annoying!
Has anyone really found the root cause and what’s the most cost effective way of fixing it? Has anyone fixed it by replacing just the pistons and little ends? What stops it happening again?
I think it’s simply big cam related on most occasions, if I had the answer to your question I’d be rich but if I was to start this topic and mines a 4.6 my post would read like yours, rebuilt engine and it’s done it from day one.
Listen to one with a really hefty cam and it’s much worse so I think it’s connected to follower action.
On a couple of occasions I’ve now used a drop of Classic 20/50 mineral in my oil changes and most of the rattle has gone away but still there when it gets hot.
Maybe that’s exactly what it is
Tolerance built into it for when things are most expanded and very hot!
It is very annoying.
Ask QBee what his new engine rattles like as he has a very Rover Based small cam so if any will be quiet it should be that one if my theory has any credence.
Interesting thread and well worth revisiting this issue
I don’t think it’s just a 5.0 problem
Listen to one with a really hefty cam and it’s much worse so I think it’s connected to follower action.
On a couple of occasions I’ve now used a drop of Classic 20/50 mineral in my oil changes and most of the rattle has gone away but still there when it gets hot.
Maybe that’s exactly what it is
Tolerance built into it for when things are most expanded and very hot!
It is very annoying.
Ask QBee what his new engine rattles like as he has a very Rover Based small cam so if any will be quiet it should be that one if my theory has any credence.
Interesting thread and well worth revisiting this issue
I don’t think it’s just a 5.0 problem
I’ve been looking for a solution to this problem too
Mine’s a 98 500 with exactly the same old symptoms, only does it as the revs drop, most noticeable when slowing for speed humps etc. It feels like there isn’t a simple and cheap fix for this and it’ll keep bugging us all then
Following with interest and hope though
Dave
Mine’s a 98 500 with exactly the same old symptoms, only does it as the revs drop, most noticeable when slowing for speed humps etc. It feels like there isn’t a simple and cheap fix for this and it’ll keep bugging us all then
Following with interest and hope though
Dave
I think that guy in the other tread has the answer half good
https://www.youtube.com/watch?v=XbCEYmtLPoQ
Its probably the adjuster, why only with certain rpm? probably has to do with the oil/lubrication system of the things...if it can not go fast enough or if it goes to fast out/in? then...
example, you see the oil hole in such thing, second from the right down>>
https://www.youtube.com/watch?v=XbCEYmtLPoQ
Its probably the adjuster, why only with certain rpm? probably has to do with the oil/lubrication system of the things...if it can not go fast enough or if it goes to fast out/in? then...
example, you see the oil hole in such thing, second from the right down>>
I was told that the design of the 500 crankshaft, to create the 5 litre capacity, causes the pistons to slap around more than usual and cause wear to the bores and piston rings, leading to oil in the bores and smoke.
My 5 litre engine went that way, hence why I didn’t just build and fit another 500 engine to replace it.
My 5 litre engine went that way, hence why I didn’t just build and fit another 500 engine to replace it.
Your forgetting to mention all the trackdays and flatout driving though bud.
Do you think your engine would be ducked if it had been used as most actually are, for plodding about with the odd acceleration thrown in.
The difference is extreme when you add all the times you lapped flat out which must be a life time of acceleration on many engines. You just did 15 years of that in about 3
You have hit the nail on the head in some ways as the little end or piston slap can be caused through worn bores.
I was reading about pistons, as you do, and modern ones ( probably all of them) and I assume ours are modern enough to be similar are actually wider at the bottom than the top which is why often you can move the top of the piston in the bore when cold. The extreme heat the crown takes expands it to its correct size when in operation so if the bores are worn this slap is more likely.
The more pronounced tap/ knock/ rattle I tend to hear on deceleration at around 1800 revs does sound more like cam related as I’d expect piston slap to occur on more than one piston if it’s general wear and be more of a vibration rather than specific tapping but I’m guessing.
Mines the 4.6 so I don’t think it’s just 5.0 related although the longer throw might add to that problem.
Mine can be a bit erratic in that sometimes I don’t hear it, if it was piston slap I’d expect to hear it constantly.
Im sure I read that it’s the piston base because its wider is what causes the wear in the bore from the slapping or rocking effect.
There’s also the little end which is supposed to get a poor oil feed but rarely does anyone seem to mention it as a problem on Rover forums or is that just cos know-ones looking!
If peeps with new con rods get it i’d say it’s not little end related.
Just noisy old design engines that don’t really like big cams or revving very high.
Do you think your engine would be ducked if it had been used as most actually are, for plodding about with the odd acceleration thrown in.
The difference is extreme when you add all the times you lapped flat out which must be a life time of acceleration on many engines. You just did 15 years of that in about 3
You have hit the nail on the head in some ways as the little end or piston slap can be caused through worn bores.
I was reading about pistons, as you do, and modern ones ( probably all of them) and I assume ours are modern enough to be similar are actually wider at the bottom than the top which is why often you can move the top of the piston in the bore when cold. The extreme heat the crown takes expands it to its correct size when in operation so if the bores are worn this slap is more likely.
The more pronounced tap/ knock/ rattle I tend to hear on deceleration at around 1800 revs does sound more like cam related as I’d expect piston slap to occur on more than one piston if it’s general wear and be more of a vibration rather than specific tapping but I’m guessing.
Mines the 4.6 so I don’t think it’s just 5.0 related although the longer throw might add to that problem.
Mine can be a bit erratic in that sometimes I don’t hear it, if it was piston slap I’d expect to hear it constantly.
Im sure I read that it’s the piston base because its wider is what causes the wear in the bore from the slapping or rocking effect.
There’s also the little end which is supposed to get a poor oil feed but rarely does anyone seem to mention it as a problem on Rover forums or is that just cos know-ones looking!
If peeps with new con rods get it i’d say it’s not little end related.
Just noisy old design engines that don’t really like big cams or revving very high.
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