300TDI Clatter

[LR1953]

Hi Guys, My wifes 1997 300TDI Disco has just developed an awful engine clatter. Can a 300TDI sound any louder, I hear you ask. It can disappear then re-occur. So Ive removed the heater plugs and valve cover to see whats going on when the engine is turned over with a socket on the crankshaft pulley. Result is No.1 exhaust valve springs shut with a click at one point and exactly one crank rotation later No.3 inlet valve springs shut with the same click noise. Timing belt is slightly overdue for replacement.
Would you suspect sticking valves (? bent stems) or worn timing belt and or gears. Your learned opinions please?

[BigJon]

It might have worn through the caps on the tops of the valves. Pop the rocker cover off and look at the valves / rockers / check the clearances.

[LR1953]

Thanks BigJon, I'll get the feeler gauge out. The valve (rocker) cover is already off. I'll need my reading glasses, but!

[AndrewGJones]

Timing belt is slightly overdue for replacement.


It's about to get a whole lot noisier if you don't get this sorted out, then it'll stop all together and be nice and quiet for a long time!. I would be suggesting put away the feeler gauges and reach for a socket set. when you say slightly over, what K's do you mean over?

[AndrewGJones]

really cool tutorial for a disco timing belt replacement...

300TDI timing belt replacement - Land Rover Technical Archive - LR4x4 - The Land Rover Forum (http://forums.lr4x4.com/index.php'showtopic=22319)

[Judo]

I'm no mechanic, but I would be fixing the noise by looking at the simple things first, like rocker clearances and caps. Timing belt maybe due and it's very wise to do it ASAP, but it doesn't sound like your problem and diving in to change the timing belt while you already have another problem is asking for confusing results. Fix one thing at a time!!

Let us know how you go in the rocker cover! :)

[LR1953]

It's about to get a whole lot noisier if you don't get this sorted out, then it'll stop all together and be nice and quiet for a long time!. I would be suggesting put away the feeler gauges and reach for a socket set. when you say slightly over, what K's do you mean over?
Andrew, odometer is 336 thousand Ks, last changed at 232 thousand. I wont be running the engine until its fixed. I have 2 Defenders with 300TDIs and never had an internal problem - plenty of alternators and water pumps of course but who hasnt? always keep a spare of eack on the shelf

[roverrescue]

Lift off the rocker gear and have a close look at all the bits that go up and down
You have all but diagnosed the problem
You need to assess whether the free play that is allowing the valves to snap shut is in the roller/follower/pushrod combination or the rocker arm valve and spring

Perhaps a check of the pushrod lash cap to rocker arm (valve) clearances before pulling the rocker arm would be in order????

S

[AndrewGJones]

Andrew, odometer is 336 thousand Ks, last changed at 232 thousand. I wont be running the engine until its fixed.

that's 104K which is around the official LR 'best case scenario" figure, but I've read a fair few opinions to change them at 70K to be safe regardless.

Stop/start driving is not best case scenario, the lower figure they give is 60K for adverse conditions, which if you think about it is closer to Oz conditions (dust, heat etc)

It says 200tdi in the link, but it has the 300tdi data as well.


http://www.landroverweb.com/Pdf-files/Timing_belt_200Tdi_interval.pdf

[Nomad9]

Hi LR1953,
If you give the engine a turn, by hand and just rock the rockers this will tell you if you have anything terminal in the rocker assy. A couple of push rod ends might have "gone soft" and worn, is the clatter at engine speed or half engine speed this will tell you where to look first, the valve train goes half the speed of the engine. At engine speed could be something amiss a bit further down.
As mentioned before could be an issue with the caps that sit on top of the valves, I had a consistent clatter at one point and found one cracked. If the noise disappears, could be a partially blocked oil feed to the head, rocker clearances don't usually fix themselves.

[LR1953]

that's 104K which is around the official LR 'best case scenario" figure, but I've read a fair few opinions to change them at 70K to be safe regardless.

Stop/start driving is not best case scenario, the lower figure they give is 60K for adverse conditions, which if you think about it is closer to Oz conditions (dust, heat etc)

It says 200tdi in the link, but it has the 300tdi data as well.


http://www.landroverweb.com/Pdf-files/Timing_belt_200Tdi_interval.pdf
This vehicle is used mainly to commute between home and the nearest train station 25ks away, 1 T intersection and 2 sets of traffic lights. Mostly a steady 80ks per hour 4 days per week. Cam belts always changed around 100 thousand ks.

[LR1953]

Thanks Marty, the curious thing is that the "click" occurs alternately with no.1 exhaust, and no.3 inlet, at exactly the same point of rotation of the crankshaft. I have the cover off the injection distributor, so will check if it "jumps"at the same point. That would lead me to assume the belt is jumping as well, and suspect the driving gear on the crankshaft "has issues" with the woodruff key. Hmmmmm.............

[wrinklearthur]

Hi LR1953

Beside those checks the other's have suggested, I would also do a check on the vacuum pump.

The gasket between the vacuum pump and the block can crush over time causing a few problems, fit a new thick gasket or a couple of thin gaskets and try that.

To find and locate the source of a noise, I would use a poor man's stethoscope, use a length of plastic tube or garden hose up to your ear and poke the other end around the running engine, you will soon find where the noise is the loudest.
.

[scanfor]

The big-ends in my 300Tdi started "rattling" at high revs, seemed strange to me no knocking at lower revs. The hard-facing was just starting to break down in a few spots. Apparently a common issue at 150k-200k on these motors.

[Blknight.aus]

have you checked the fuel filter?

[LR1953]

Hi All, just over a week ago I posted re "300TDI Clatter". I now have the answer (cause) and hopefully the extent of the results. Pulled the timing case cover off and discovered that the bolt holding the drive gear to the front of the camshaft had worked loose. This allowed the cam a small amount of uncontrolled rotation, ie was moving in and out of synch with crankshaft and injector pump. See attached pictures of worn/damaged boss still bolted to the pressed steel gear and the replacement boss. Wear is apparent on both front and back of the boss. The pin (not shown) which locates the boss on the front of the camshaft appears OK. Pushrods all look straight and I'm told they bend before valve stems in this kind of situation. So....... a new cambelt kit and all should be good!

[Scouse]

Threads merged.

If you manage to resolve an issue, just carry on from the original thread. That way the symptom, cause & solution are all in one place.

:)

[AndrewGJones]

;) I guess we won't be seeing you in the isuzu section asking about replacing a blown engine then?

these belts are the reason I have not been able to enjoy my LR's; such a bloody stooopid idea to put a lacky band in control of the most important job in the engine. Also the reason I was bluntly insisting you check it first; despite assurances otherwise, I just do not trust them at any Km mark, though not entirely sure why that is considering I've never experienced one snapping.

i suppose they are like the damocles sword of landrover ownership.

[Scouse]

these belts are the reason I have not been able to enjoy my LR's; such a bloody stooopid idea to put a lacky band in control of the most important job in the engine. Also the reason I was bluntly insisting you check it first; despite assurances otherwise, I just do not trust them at any Km mark, though not entirely sure why that is considering I've never experienced one snapping.

To be fair, it wasn't a belt issue with the car. It was a loose bolt on the camshaft gear - the same bolt that secures a chain driven gear.

[AndrewGJones]

The belt causes that wear. that's why the full 'belt kit' includes a new gear and tensioner.

i think the belt resonates at approximately 'A flat', which has always been a particularly difficult key to play in. :cool:

[DeanoH]

The belt causes that wear. that's why the full 'belt kit' includes a new gear and tensioner............................. :cool:


errr.................................How exactly does the timing belt cause the retaining bolt to come loose to create this wear. :confused:

Perhaps if it 'resonated' in common as muck C major all would be good. ;)

The reason the full 'belt kit' includes a new gear, tensioner and idler plus retaining bolts is because it is an upgrade from the original design. :) These parts are different to the original.

Deano :)

[AndrewGJones]

errr.................................How exactly does the timing belt cause the retaining bolt to come loose to create this wear. :confused:

Perhaps if it 'resonated' in common as muck C major all would be good. ;)

The reason the full 'belt kit' includes a new gear, tensioner and idler plus retaining bolts is because it is an upgrade from the original design. :) These parts are different to the original.

Deano :)

It causes it the same way it will wear out the new ones in time; by being fundamentally a bad idea. the physics of shaking bolts loose is not something even I could pretend to know (and I quite liked the Pretenders, always played songs in happy keys..).,The how is not probably as important as the why;and that 'why' is because it was holding a lacky band in place that really should not be in there to start with if they had not been so worried about getting there arse kicked by accountants and salesmen (this is too noisy and expensive -put a rubber band in it will ya?).

[AndrewGJones]

it took me a little while, but I finally got the metaphor for what I'm saying;

"the fact that is was the bullet killed the bloke doesn't excuse the smoking gun'

If we had been talking face to face then I would have said something like "what you are saying is like a..um....<insert hour long pause here>...yeah, it's like blaming the bullet not the gun" :)

[LR1953]

Gentlemen, its all fixed and good. A new belt kit plus replacement boss, bolt and locating pin for the camshaft sprocket. Job done. purrs like a happy erm,.....cat. For those who dont like the lacky band thingy, there was a replacement gear kit available in the UK for about 1,100 quid sterling. All sorts of claims for improved power and efficiency - and not much more noise.
My other car, the going-to-town limo, is a W124 Mercedes 300D: straight 6 naturally aspirated diesel with single overhead cam, double roller chain driven, hydraulic lifters - Bewdiful! and quiet, with over 500,000 ks on the clock.

[rick130]

Gentlemen, its all fixed and good. A new belt kit plus replacement boss, bolt and locating pin for the camshaft sprocket. Job done. purrs like a happy erm,.....cat. For those who dont like the lacky band thingy, there was a replacement gear kit available in the UK for about 1,100 quid sterling. All sorts of claims for improved power and efficiency - and not much more noise.
My other car, the going-to-town limo, is a W124 Mercedes 300D: straight 6 naturally aspirated diesel with single overhead cam, double roller chain driven, hydraulic lifters - Bewdiful! and quiet, with over 500,000 ks on the clock.

The Zeuss timing gear kits were bad.

Very few who fitted them didn't end up regretting the decision.

The timing belt is OK if done when it's due.

[justinc]

Absolutely nothing wrong with the Tdi using a cambelt, if fitted corrctly and all fasteners correctly torqued and the belt changed at the right interval FOR THE CONDITIONS then they are no worse than any other camshaft drive IMO.
At least when / if they fail they generally only bend a few straight things, a gear set or chain will do far more damage if failure occurs.

I disagree about the belt design being the cause in this case. I have replaced many hundreds of tdi belts I would estimate, and the only instance where I have seen a bolt come adrift and cause problems was one that wasn't tightened correctly in the first place....

JC