ENGINE NOISE...

[matbor]

I'm not sure if i'm hearing things, but my v8 is making a noise, like a constant tapping noise, this only happens while it is warming up (about 5 mins then disappears, well nearly completely !!)

I have just change the oil about 3,000 kms ago (did most of those km's in the last week !!!) Use Penrite HPR15, engine has done 128,000km's now.

any ideas ??

[defute]

Hey Matbor,

it sounds as though you have noisy hydralic lifters.

If the oil you are using is too thin - causing the lifters to bleed down while the engine is switched off, the lifters are worn or the engine's oil pressure is low - it can take longer than normal to fill the lifters full of oil on start up. This will cause a tapping / knocking noise. This noise will normally be isolated to the top half of the engine.

It may pay to check the engine's oil pressure and possibly try running a slightly thicker oil.

[matbor]

thanks, how would i find out the enigne's oil pressure ?

[bigbugga]

I had this same problem and was told the same this from my LR dealer.
$x amount of dollars to fix, was a big number too


But
He then turned about and for $10 ran a cleaning agent through the oil for me.
After 4 days no more tapping on start up, and that was 8 months ago.

[matbor]

do you know what sort of cleaning agent they put though the engine ?

Has anyone done this before ? What do u have to do to flush the engine ?

I have read a little up on this, but not what products are available in australia ! Also any suggestion's on what oil i should put in after this ? Have been using Penrite HPR15 (every 5000kms, new oil and fliter) with no problems until now. Should i put that in again to see if the flushing agent fixes the problem or change to a different brand oil !!

I have also read somewhere that changing to a thinner oil will help fix the problem, because more than likely the oil passages are blocked up and if you run a thinner oil though the system the degrent in the thinner oil will help break down the blockage. Is this true ?

Sorry for so many questions.

matt.

[matbor]

has anyone got any ideas ?

Thanks

[Defender200Tdi]

I've read a bit about this on other forums (fora?) in the past. It was suggested that rather than using a flushing agent, you could try a normal diesel engine oil for a few thousand km's. The diesel oils are very high in detergents & dispersants which will achieve much the same thing as a cleaning agent, but be a bit more gentle and take more time. My only concern with flushing agents (or even diesel oil) would be if your engine was badly worn and the cleaning removed carbon deposits from your rings which were keeping the compression up, but at only 128,000km I wouldn't have thought that your engine would have that sort of problem.


Paul style_emoticons/<#EMO_DIR#>/biggrin.gif

[Defender200Tdi]

I just had another thought on this. I seem to recall that the 3.9 V8's went through a stage where they were developing excessive end float in the cam shaft. This produced a knocking noise that was a bit deeper and slower than the tappet rattle. I think Landrover developed a fix for it in the mid 90's. I'm sure Defute would know more about it. You there Marcel???



Paul style_emoticons/<#EMO_DIR#>/biggrin.gif

[LandyAndy]

Hi
Wyyns "Tune Up" works a treat on the same problem in sticky lifters in Falcon 6 X flow motors.
I have the same problem at the moment in my 202 powered Ser3,that has developed since the weather has cooled down.Im running penrite HPR50 and suspect its too thick till warmup.I bought diesel oil to do an oil change last weekend for the exact reason in the last post.Perhaps your HPR15 is a little too thin,maybe use the "Tune Up" for 500ks or so then the Diesel oil??????????
My 202 only runs LPG and the oil is as clean as the day it went in so I dont think carbon is a problem for me.
Does your oil blacken up quickly? If so diesel oil may increase your oil consumption,this may not be that bad as you are using a very light grade,going up to HPR20 or 30 would cure that.I had a falcon that was using up to 4 lts of GTX a week,changing over to HPR50 droped it to 4lts a month and I got another 18 months out of the motor till I re-built it.
Andrew

[defute]

Hey Matbor / Paul,

sorry for the delay guys - I'm working on the Press Launch of the new Jaguar XJ6 into our market in Melbourne - we've just finished preparing the vehicles for tommorow's round of journos!!

The knocking noise that Defender200Tdi has mentioned effected 3.9lt V8s and was caused when the camshaft moved backwards and forwards in the cylinder block due to excessive end float.

Camshaft end float can be measured by either removing the inlet manifold or front timing cover and checking the cams extremes of movement with a dial guage.

From memory (and I stress 'memory' - and I can confirm this when I get back to the office) there were 3 possible fixes that could be employed depended on the amount of end float that the camshaft had and the vehicle's engine# -

1. fitting a 'button' to the nose of the camshaft and machining (filing) it to the appropriate / calculated thickness to bring back within spec 'camshaft end float'. Fitment of the 'button' reduced cam end float by allowing the button to butt against the inside of the engine's front timing cover as the cam moved within the cylinder block. This contact was not audible due to the type of material that the button was constructed from and did not cause any damage to the timing cover. This is the cheapest fix!!

2. fitting a 'camshaft retaining plate' which was bolted to the front of the cylinder block and machining it to the appropriate / calculated thickness to bring back within spec 'camshaft end float'. The fitment of the retaining plate is not much more expensive than the 'button' fix but requires more effort to machine to size due to it's design!!

3. fitting a new camshaft, lifters and camshaft retaining plate. This is by far the most expensive fix and still requires the retaining plate to be machined to the correct thickness!!

I hope this answers your questions!!

[matbor]

Thanks guys, will go down to the auto shop tonight or on the weekend and get some Wyyns "Tune Up" or something similar. Not to sure about using diesel oil yet.... but wil try using HPR20.

Will let you know how i go.

Matt.

[crawfy]

Can remember having the same problem on our V81 Disco and I can remember a mate putting a Nulon or Morey's product in? Check these two out, I know our Disco made the same noise until warmed up, and it only had 139,000klm on the clock, and we traded the Disco in with around 190k so check it out it worked for us style_emoticons/<#EMO_DIR#>/smile.gif

[Phoenix]

Originally posted by LandyAndy
I have the same problem at the moment in my 202 powered Ser3,that has developed since the weather has cooled down.Im running penrite HPR50 and suspect its too thick till warmup.

I had that problem before I changed to penrite, but I use HPR40 in the 173 now, and since I changed it doesn't do it at all anymore. It used to before warm up, but not now.

[RichardK]

Some years ago when I was running the 3.5 in the RR I had a considerable amount of sludge buildup under the rocker covers, having been around for some time I recalled "flushing Oil" but it is no longer available so I rang Shell and they advised me that the use of deisel oil would do the job of cleaning the internals of the engine. They suggested running it for around 1000 Km's and replacing with the recommended oil.
I did this and was surprised at the amount of gunk that the deisel oil removed from the engine.
Hope this is of assistance.

[LandyAndy]

Hi Matbor
Have a look at the specs on both petrol and diesel oils,I think you will find they"overlap".The main difference is diesel oils contain detergents to remove the soot in the diesel burning process.These detergents can be usefull in a petrol engine as long as it isnt badly worn.
I once worked on a huge market garden,the young blokes always pinched oil(diesel for the tractors) for thier thrash heaps.When they blew their motors up they wouldnt belive it was due to using diesel oil in a worn out motor and thrashing it.The oil removes the carbon build up in the motor which is actually providing connpression via the rings.
In a health motor the diesel oil will only do good if used for short periods
Andrew

[matbor]

Spoke to my mechanic friend today and he wants to have a quick look at the car on saturday morning, but he thinks it just needs a clean out, as you all have just suggested.

Very interesting about diesel oil and using it in a petrol engine, will have to remember that. Do you think it would be a good idea to do that every say 20000km's for example, on a engine that isn't wore of course !!

matt.

[matbor]

Well lucky i went to my mechanic, all it was the exhaust manifold bolts where a bit lose, he nipped them up and all fine !!!

Thanks again for the info guys.

Matt.