Thread: 07 Puma Engine Rattle

Originally Posted by solmanic

OK, how about the possibility that it is somehow related to the fuel pump not working correctly when cold? Or a seal

somewhere along the fuel line that's leaking air into the system whilst cold?

The thing is, maybe the rattle isn't only happening between gear changes or at idle/overrun, but maybe it is also happening under load and we can't detect it then with all the other noise? Once recently I was accelerating uphill about the same distance from home when the rattle usually occurs, and I got a brief, distinctly harsh spot of revving - like the rattle only different because the driving scenario was different.

This is what Ian suggested initially to the dealer.....unfortunately they don't really listen to us and go by what they know and what LR UK tell them.

I don't believe it is doing it when under load......as I think if it behaved the same way it does it when its cold it would lose power..
When it does it when its cold, if its bad you can not accelerate!

Ours has happened more so when coming on boost. So engine noise is already elevated and we can definitely hear it.

Originally Posted by Captain_Rightfoot

My apologies for the hi-jack!

From page 73 of my manual...

"Warming-up
DO NOT (manual uses caps for emphasis) warm-up the engine by allowing it to idle at slow speed. However remember that the diesel engine must not run above idle speed until the oil pressure light extinguishes.

In the interests of fuel economy, it is advisable to drive the vehicle straight away, as soon as the oil pressure warning light extinguishes.

Remember that harsh acceleration and labouring the engine before the normal operating temperature has been reached can damage the engine."


Me, because of what it says in the manual...

Without wanting to add to a highjack - but I thought this was an interesting aside....

There is no such warning anywhere in the Puma's handbook - so LR have taken it out of the new manual.

I have Googled the topic and the majority of answers I can find suggest that, in cold operating temps, warming up at idle for up to 5 minutes, or more specifically, to (160F) is optimal, although Blknight disagrees with this (PM).

Another reference suggests that all modern engines are "run in" at manufacture time - in that they are operated over the rev range (flogged I gather). According to this source, cylinder glazing cannot subsequently occur and the engine can be idled to warm up without any adverse effect. My engine uses no oil, has never exhibited the issue originally discussed, and appears to use less fuel than most other Pumas. Again, not gloating - just my simple observations.

At any rate - LR have taken this advice out of the manual. I was pretty sure I read the thing like scripture when I got the vehicle and followed all instructions to the letter.

Originally Posted by Scallops

Another reference suggests that all modern engines are "run in" at manufacture time - in that they are operated over the rev range (flogged I gather)....

At any rate - LR have taken this advice out of the manual. I was pretty sure I read the thing like scripture when I got the vehicle and followed all instructions to the letter.

Yes, they are indeed flogged in the factory. I have witnessed it - quite impressive. At the end of the Defender line there is a rolling road in a booth. Each vehicle is driven onto it and they rev the snot out of it. Then they jam on the brakes - to test ABS etc - and the machine bucks and jumps before they then calmly drive it out into the yard.

The "no warm up" info wasn't in the manual I didn't think. It was posted from some other source, but heavily backed up by the gurus on here. It's not that you just turn the vehicle on and drive off at full speed, it's more that you don't just leave it sitting on idle for ages.

As for your vehicle using less fuel... you drive like my grandmother so it's no surprise .



...Although she did drive a Hillman Hunter, and rarely off-road.

Originally Posted by Scallops

At any rate - LR have taken this advice out of the manual. I was pretty sure I read the thing like scripture when I got the vehicle and followed all instructions to the letter.

I don't know

Maybe they did it to try and cause heated discussions on the internets There is someone back at LR HQ right now chortling to him/herself

Originally Posted by Solmanic

As for your vehicle using less fuel... you drive like my grandmother so it's no surprise .

When we meet you on a AULRO drive and we come to that big hill.... we'll be chanting.. go on Scallops... drive it like your grandma borrowed it to drive to church on sunday...

Originally Posted by solmanic

The "no warm up" info wasn't in the manual I didn't think. It was posted from some other source, but heavily backed up by the gurus on here.

Read between the lines - I think this needs more answers from our dealers...

[I]Title: 2.4 Puma Engine Knock Noise.
Type: LD - Defender - All Years - Special Service Messages - Engine
Name / Part No: SSM38792
Info Type: Service Bulletins
Version No: 1
Date Uploaded: 21 Jul 2008
Models: LD - Defender
Title: 2.4 Puma Engine Knock Noise.
Last Modified: 21-JUL-2008 09:44
Category: Engine
Symptom: 497000 Engine Noise

Content Issue: Heavy audible knocking heard on start up.
Cause: On start up oil pressures can cause the piston cooling jets, (PCJ), to latch into a zero flow condition. Due to hysteresis effect in design the jets do not unlatch until the engine is warm and the oil pressures lower again. During this time with no pressurized oil jet flow to the lower pistons / cylinder bores, overheat and scuff conditions / damage can occur.

Action: Replace the engine assay but ensure only engines post serial # ELD00080707063602 are used.
This condition will not occur on vehicles post assured Vin# 9A767162.
Engines post the info above are fitted with modified PCJ internal springs and this issue is now closed.

Now I'm no expert (clearly ) - but I don't want to start driving a vehicle with no pressurised oil jet flow to the lower pistons etc etc.

Perhaps this has happened to vehicles that make this rattle.

PS - One final point from me on this - I rang the dealer to ask them their opinion on warming up the Puma engine as I'm doing - for what it is worth, they said it was, "a good idea and to continue doing so". Then I rang MR Automotive - their advice? "Warming up the engine as you're doing will cause no damage and is the best thing you can do".

And as to driving like a Grandpa - guilty as charged, but I'll have a crack at driving it anywhere.

I have already presented this TB to the dealer with several pointed questions - naturally they dismissed it as irrelevant. I have to admit though, I can't say I've experienced a "Heavy audible knocking heard on start up" like the one referred to here. The rattle has existed pretty much from new and has only ever been a "rattle" which never occurs immediately on start-up, but always a few minutes later. Besides that , we now have evidence of 2009 spec vehicles exhibiting the same rattle (One Iota).

as said before...it is not on start up and its not a knock its a rattle.

Got same Rattle in my Puma this morning. First time I have heard it. This morning it was cool and damp in Perth. Noise only lasted a couple of seconds but code warning light went on. I drove the vehicle for about 1 hour with no other symptems. Took it to Barbagallo's to get code cleared, sevice sugested if it happens again book it in. Could not red code, machine was being used. will and wait and see
Allan