Hammering noise when under power

In the last few weeks I have noticed that my 2000 plate L series is getting noisy. Basically there is like a subsonic thumping that appears to be in time with the engine firing, while the engine is under drive and stops when the power is taken off. It definately is linked to the engine RPM and not with road speed. Further more I can feel the vibration as I drive along. However, the idling engine sounds fine for a direct injection. Also at higher RPM it seems to dissappear. I initially thought it was tyre pressures causing the VC to slip but I've mucked about with the pressures and can safely say its not that. I also wondered if it was the winter diesel mix causing a harder knock but I'm not sure on that. I thought I was imagining it until the family started asking what the noise was all about. Trouble is I am really begining to wonder if its the bottom end of the engine. If so I need to diagnose quickly before something nasty happens. Any ideas out there. Many thanks, Dave

Update. Have replaced air filter element and added injector cleaner to fuel. Checked engine oil level again and is still okay. Considering checking compression and oil pressure, although for the latter I have no basis of comparison. Checked engine mounts and are all okay. Car records 88,000 miles, not high for a diesel.

Anyone else had problems with the big ends / mains on this car, or is this unusual? As far as I'm aware it has been serviced regularly, although ther oil change has been at 10,000 miles instead of the manufacturers recommended 6000 miles.

Further updates.

Checked engine mounts and all okay. Changed engine oil and filter, nothing unusual there. Checked front drive shafts, slight play in on-side CV joint. Not sure this is the reason as the problem seems to be related to engine speed not car speed.

Admitted defeat, car off to LR specialist tomorrow. His opinion is the L series is a tough unit and he doubts the problem is there.

Meanwhile had to go out early this morning on the icy roads. Outstanding performance by the LR. Worth keeping it up together me thinks.

Will report progress.

Well this one is turning out to be very interesting, if it was someone elses car that is. The LR specialist, after an extensive road test and several under bonnet and other checks, concluded that he couldn't tell exactly what was causing the noise but he had the following observations.

# The engine was loud over all, which I was surprised to hear.

# The engine performance is 'flat', it has little 'go'. He did admit he wasn't using the power band much as we were interested in the 2 - 3 thou rev band where the noises are most noticable. However, again I was surprised to hear this as I thought it was going pretty well but there again I have no basis of comparison.

# The sound of the problem is rev related. If it was a petrol it would be pinking. He commented that it sounded like it was exhaust related and suspected the engine was losing compression to the exhaust system, either by a timing error or due to an exhaust valve seating problem or burning.

# The exhaust gases are hotter than expected, also pointing to the engine firing into the exhaust manifold.

# Convinced it is not a bottom end problem.

Primary recommendation is to do a compression test. This might be leading to an 'olf with 'er 'ead' job. Okay, that hell of a lot easier than a bottom end rebuild but not the best news I would have liked. Also noted that the timing belts need changing so that'll roll into one job.

Anyone experienced valve gear problems?

Just for the record, I really like the Freelander and enjoy driving it. Otherwise it would be -

:violent: FREELANDER

injection pump timing

Really does sound like classic incorrect injection pump timing - applicable to non common-rail diesels

I'm not familiar with the L series, but older transits would do this if the cam belt had slipped a tooth

Thanks for your thoughts people. As the L series has two timing belts (First drives crank to cam plus water pump, second drives cam to pump) I assume that the first belt is the most likely candidate to have slipped. I will check both directly as the question has to be asked as to why a slippage occurred.

Could be either belt - might have a broken tensioner

Sheer genius diagnosis!! The crank to cam belt is flapping about in the breeze. The tensioner must have come loose. The belt must have been jumping teeth and the performance is deteriorating as a result. How far off from valve to piston contact are we??? .

Having encountered problems getting the upper cover off I consulted the Haynes manual for advice, which considered both covers.

:screaming_bug_eye_f :wtf: :screaming_bug_eye_f

Time to consult the forum. Surely you don't have to move the engine in the engine bay to get the covers off.......... do you????

Many thanks for your help here. Spot on.

Dave

Glad that was of help

I wouldn't reccomend running the engine.

Afraid I have no experience of the L series engine, but I shouldn't think you have to move it to remove the covers or change the belts, just skinny hands

You will need locking pins - or fabricate your own - for the crank and cam to set the timing etc.

Must be some relief, eh?

The specialist should have picked up on the timing.

The subsonic thump was a lazy piston/con rod, caused by the lack of firing.

Not sure about the l-series covers, more than likely 8mm bolts holding it and lots of em, sometimes more than are needed.

Northern Irelander said:

The specialist should have picked up on the timing.

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There was a passing reference - but I was surprised that they had not featured this idea more.

but then, I am not a "specialist"

The specialist did suggest injection timing but didn't forward the opinion of there being a mecahnical reason. He was happily slagging off the electronic management, probably like most of us, he doesn't understand it. I can't really complain, he didn't charge me anything for his time.

Some relief indeed Mark2 and I am much obliged to STE220 and yourself for both spotting the logical reason. Many thanks once again.

On the subject of the removal of the covers I have had a good look with a torch and as far as I can see there is no access. The bolt heads are recessed so there is no go with a flat spanner, its got to be a socket. There's about 5mm clearance between the cover and the inner wing. It so tight.

I'm going to give the LR guy a call tomorrow to see if he has any tips. I am thinking 'is it possible to bore through the inner wing to give access to the bolts??'. Maybe not but if you don't ask the question.....

The Freelander is officially off the road until I can get this fixed. All I've got to do now is ask the wife if I can use her car for a few days....... :hug: :kiss: :car: :argue:

Have you removed the inner wing access panel?

Mark2 said:

Have you removed the inner wing access panel?

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Not actually removed it but I did pull it back while looking from underneath. It gives plenty of access to the aux drive belt and, undoubtidly the crank timing pully when the covers are off, however the bolts that hold the covers are higher up and behind the structural body work. I need a better look in daylight.

fair enough, best of luck.

grind down an 8mm 1/4" socket, so that it is shorter, then you can get in better, then grip the socket with a pair of mole grips! thats how i did it!

ste220 said:

grind down an 8mm 1/4" socket, so that it is shorter, then you can get in better, then grip the socket with a pair of mole grips! thats how i did it!

Click to expand...

Thanks for the tip. Just been on to the LR guy again. He says that access can be achieved by dropping the engine off the off-side mount. This will give access to the bolts through the wheel arch.

I think I will try your method and his method would be a last resort. Been on to the Land Rover Orphanage in Chippenham www.landroverorphaage.com for a new set of timing belts. Waiting for the quote.

Many thanks, Dave

Good news, I've got the problem bolts out by lifting the engine on the jack. Had to move the power steering pipes to get there and have now got the top cover off.

Bad news. The belt isn't that loose, its not tight but I'm not convinced its loose enough to slip.

Bad news. The crankshaft pulley bolt is solid and wouldn't shift even using a high strength socket and a 2 ft bar. Feared the head was going to sheer so I gave up for now but stuck on what to do next.

Bad news. The PAS pump is now leaking hydralic oil. :hurt:

:violent: FREELANDER