View Full Version : 300 tdi pushrods popping out of place
ScottW
28th August 2010, 02:04 PM
After getting the car running again --> 300tdi misfire (http://www.aulro.com/afvb/technical-chatter/111999-300tdi-misfire-smoke.html),
it seems pushrod number 3 has once again popped out of place at the bottom this morning, leaving the car to run on 3 cylinders.
I'm guessing that the little lifter bit that sits on the cam roller is collapsed/broken and so is letting the pushrod slide down the side somehow.
Is there a way to rectify this without removing the head? Does this sort of thing happen often?
Obviously whoever put the new head on the engine overlooked something or not checked the condition of the old (or new) lifters as they went in. We might have to ring the guy who sold him the car to see if he paid a shop to do it or if it was a diy job. (Not really that keen on ringing the guy we bought the car off to tell him it's broken though.)
Once again my father has had to revert to the old reliable P38 for transport. :D But Mum will want that back come monday.
clean32
28th August 2010, 02:19 PM
After getting the car running again --> 300tdi misfire (http://www.aulro.com/afvb/technical-chatter/111999-300tdi-misfire-smoke.html),
it seems pushrod number 3 has once again popped out of place at the bottom this morning, leaving the car to run on 3 cylinders.
I'm guessing that the little lifter bit that sits on the cam roller is collapsed/broken and so is letting the pushrod slide down the side somehow.
Is there a way to rectify this without removing the head? Does this sort of thing happen often?
Obviously whoever put the new head on the engine overlooked something or not checked the condition of the old (or new) lifters as they went in. We might have to ring the guy who sold him the car to see if he paid a shop to do it or if it was a diy job. (Not really that keen on ringing the guy we bought the car off to tell him it's broken though.)
Once again my father has had to revert to the old reliable P38 for transport. :D But Mum will want that back come monday.
check that the rocker arm shaft isint broken under the caps.
check that the cap thingys havent droped down and are sitting ontop or under the lifter
ScottW
28th August 2010, 02:23 PM
We have watched the engine kick over. The 3rd rocker doesn't move. The pushrod doesn't come up to push the rocker arm. We have pulled off the rocker shaft and it's all good. It is definitely the pushrod not lifting up.
The pushrod is straight and looks 100% normal.
clean32
28th August 2010, 02:26 PM
We have watched the engine kick over. The 3rd rocker doesn't move. The pushrod doesn't come up to push the rocker arm. We have pulled off the rocker shaft and it's all good. It is definitely the pushrod not lifting up.
The pushrod is straight and looks 100% normal.
50 bucks says that some one droped one cap thingy down the hole before droping in the cam follower
ScottW
28th August 2010, 02:48 PM
50 bucks says that some one droped one cap thingy down the hole before droping in the cam follower
Now, that would suck. But it wouldn't explain why it runs fine and gets normal lift, them all of a sudden, no lift.
I think a bright torch and some careful examination may be required.
clean32
28th August 2010, 05:47 PM
Now, that would suck. But it wouldn't explain why it runs fine and gets normal lift, them all of a sudden, no lift.
I think a bright torch and some careful examination may be required.
$50 bucks.
another $25 says she did a cam belt at some time.
roverrescue
28th August 2010, 09:33 PM
To answer this:
"Is there a way to rectify this without removing the head? Does this sort of thing happen often?"
In order to get the slides, rollers and followers out you need the head off.
In regards to happening often...
In my limited experience the cam follower assemblies are pretty hardy. Im sure anything can happen though and some part of the follower assembly on pot2 inlet may have collapsed. I wouldnt think that a falling lash cap would cause too many troubles? More than likely just end up in the sump kissing the cam on the way down?
Hang on a minute just realsied... if its the third pushrod/ follower assembly from front (Pot 2 inlet valve) well you may be able to at least have a gander at the problem by removing the oil filter assembly/ baffle mount. Once this is off from memory you can at least see into the cam lobe and maybe see some damage. When it all boils down though I can see an engine pull in your future!
Steve
ScottW
30th August 2010, 07:49 AM
My father had a look at it this morning. It looks like the edge of the brass piece has broken off inside there and that is allowing the pushrod to slip down the side a little. Today will be spent putting the P76 back into his rangie to drive in the meantime (leaking oil from the small welsh plugs at teh back of the cam) and then the rest of the week will be spent making sure the disco gives him no more problems for the next 80 000km.
ScottW
31st August 2010, 08:24 PM
Looks like the lifters have deformed and chipped.
Not a common problem from what I hear. I'm guessing the very slack valve clearances have allowed the pushrods to hammer the lifters and deform them, and eventually break the side out.
Pulling the head was very easy. The head is brand spanking new. There are also cross hatch marks on the bores from where they have been machined, so it really doesn't look like a 300000km engine. Hopefully with a new set of lifters in there, the car will be running sweet for a long time. :D
roverrescue
31st August 2010, 08:54 PM
Thanks for the followup. Thatll do it!
I guess thats why the valve clearances are a 10,000km service item.
Keep an eye on the clearances and the lash caps.
Steve
MinniTheMoocha
31st August 2010, 10:06 PM
Sorry to see the damage done you your motor. Glad you are getting on top of it.
I remember when replacing the head on my 300Tdi a warning about fitting the pushrods and that is to make sure that they are seated correctly in the lifter depressions.
If they were just sitting on top and tappets adjusted in that position then when it lifts it could have caused the type of damage shown.
Did you find the metal fragments in the sump?
It might be advisable to replace the pushrods just to be safe that they are not bent.
Interested to know how you get on.
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