Jump to content

300 TDi tappet clearances


Recommended Posts

My son's TDi developed some tappit noise recently. When we checked clearances, they were all a bit loose, but no 7 had quite a big gap

We adjusted them, rechecked, and they were fine. Today he complained about another loud tapping sound on the right hand side of the engine, and some loss of power

I took it for a short ride, the sound of the engine changed suddenly and sounded like it was running on 3 cylinders. And then the loud tapping sound made itself heard, as well as a knocking sound towards the front of the engine

We towed the Disco back home, and just removed the tappit cover to see if anything looked out of place. That self same no 7 tappit has a clearance of about 2mm !

We removed the injectors as well, but visually they look OK, although they have done 300 000km

Any idea why the tappit clearance has increased ?

Any idea on what might be wrong with the engine ? (Yes, I know it's difficult to identify the problem from the above description, but maybe somebody had a similiar experience ?)

All help appreciated

Link to comment
Share on other sites

are the valve caps in place, 8 little discs in the spring retainer centre,

valve clearance is 0.20mm all 8 valves cold engine.

if it's changing maybe the ball of the adjuster is worn or the nuts are not holding when tightened.

I do not know what the valve caps look like. I had a look, below every lifter sits a little round object on top of the valve stem. All the valves have that

Link to comment
Share on other sites

I set mine at 0.015 - sert with the engine stone mother-less cold I found 0.20 was too much and when hot (normal running temperature) there was around 0.02-4 clearance, a good gap for occassional high revs.

Yes, I set the valve clearances at 0.2 with the engine cold. (I think the owner's manual state the same clearance for hot and cold)

Link to comment
Share on other sites

Check that the rocker shaft is not broken. If the threads in the head for the rocker shaft studs strip, the rocker shaft can move and break, giving erratic clearances and valve overlap.


Thanks Mo, I just checked that, and the shaft is still OK

Link to comment
Share on other sites

Did you actually take the shaft out to check?

Definitely check the shaft mounts haven't come loose too.

OK feedback on this.

I took out the rocker shaft, pulled, twisted, nothing ! OK, now that I have determined that the shaft was intact, and nothing else showed up, we decided to go deeper. Removed the head. Pistons 3&4 were quite clean, with whitish markings on the top. I took out the pistons (the bores are so good, honing marks look like they had never seen a piston !), still nothing.

I then found a local guy that works on LR's and who knows the TDi's well. I told him about the strange noise and loss of power. "Oh", said he, "You got a broken rocker shaft" I told him that the shaft was removed, checked, shaken, nothing. "Take it apart" said he.

So into the garage I went, picked up the rocker shaft, and................. it fell apart in my hands !!!!!!!!!!!!! Broken off clean in one of the landings

OK, "I told you so" is in order now :D. I never knew I could feel so relieved to find a broken part :i-m_so_happy:

What this has taught me is to add a spare rocker shaft to my spares bin when I go bushcamping

And to believe the good advice that the fudi's on this forum give :rtfm:

Link to comment
Share on other sites

  • 5 years later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy