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Major Black
13th February 2011, 03:22 PM
I have just replaced the head in my car due to a crack between the valves in number 6 cyclinder. Put new head back on the patrol & now have what appears to be a loud knocking noise, possibly a piston slapping.

I have checked all timing & this appears to be all okay.

Any suggestions on what this maybe or has anyone had similar problems.:blowup:

Bob
13th February 2011, 04:47 PM
Diesel or Petrol

If it is Petrol just for the heck of it check that Plug Leads are on the correct cylinders

Finly Owner
13th February 2011, 09:19 PM
did you seat all the push rods correctly?

Major Black
14th February 2011, 08:17 AM
No its a Diesel! Over head cam, so no push rods....Have spoken to a few people & could possibly be the timing is wrong!

YNOT
14th February 2011, 03:56 PM
How does the engine run otherwise?
It could be cam timing related or something to do with the assembly of the rocker gear.

Just a tip but if your going to ask a question about your engine, tell us what engine it is - or put it in your signiture like some others have done.

Tony

Major Black
14th February 2011, 07:01 PM
Thanks for that, have checked the timing & all is good there. One would hope that as the new head was done at a local business they would have done it all properly. Hubby is going to check the assembly of the rocker gear. Just hoping for an easy outcome! If there ever is any!

Major Black
14th February 2011, 07:16 PM
and sorry its a 2.8l Diesel

Major Black
14th February 2011, 07:20 PM
YNOT- the Engine appears to be running fine otherwise, no other issues at all. I think its a case of one by one elimination with what could be wrong with it.

YNOT
14th February 2011, 07:45 PM
As soon as you mentioned it was overhead cam I figured it was an RD28, a look back at your introduction confirmed it.
I'm assuming the noise was not there before the head came off because you did not mention it? At the moment I'm thinking the most likely cause is a valve lifter not set correctly.
With the bonnet up and the engine idling does the noise seem to be a deep knock from low down in the engine, or more of a loud tap from the top end?

Tony

Major Black
14th February 2011, 07:52 PM
The noise wasn't there before we had our head replaced. With the bonnet up the noise is a loud tap in the top end, this tap doesn't start when turning over just when its running.

the ferret
14th February 2011, 08:45 PM
Is it a clack clack clack, nung nung nung, a gnuck gnuck gnuck or a clunk clunk clunk, don't laugh, the answer will help Tony a lot to identify the problem.

YNOT
14th February 2011, 08:58 PM
The noise wasn't there before we had our head replaced. With the bonnet up the noise is a loud tap in the top end, this tap doesn't start when turning over just when its running.

In that case I will stick to my earlier train of thought and suspect an incorrectly set lifter. I would take the car to the local business that reco'd the head and let them have a listen to it.

Tony

Major Black
14th February 2011, 09:21 PM
the sound is more a slap slap slap! And a bloody loud one at that!

YNOT
14th February 2011, 09:27 PM
Can you feel it through the plastic timing belt cover?

Try using a short length of garden hose as a stethascope, hold one end to your ear and touch the other end on different parts of the engine ***be careful to stay away from fan belts etc*** and listen for where the noise is loudest.

Tony

YNOT
14th February 2011, 10:29 PM
Thread cleaned up to keep it on track.

Tony

Major Black
15th February 2011, 08:03 AM
Thanks, Tony. I am getting hubby to put it all together at some stage today to organise a tow truck over to the place in which we had the new head come from. Its going to be a clash as they are adamant that there is nothing wrong with it! Fingers crossed for our sake that its an error on their end, as paying out $2600.00 for new head & over haul has hit the pocket hard.

Kat

Bigrig
15th February 2011, 08:23 AM
Thanks, Tony. I am getting hubby to put it all together at some stage today to organise a tow truck over to the place in which we had the new head come from. Its going to be a clash as they are adamant that there is nothing wrong with it! Fingers crossed for our sake that its an error on their end, as paying out $2600.00 for new head & over haul has hit the pocket hard.

Kat

Good luck with it mate - don't take a backward step on it either. You paid for service and sounds like you ended up with more problems ...

Major Black
15th February 2011, 08:26 AM
I did well I have the company coming over today to check it out...will let you all know the outcome to it!

Major Black
15th February 2011, 05:55 PM
well the guys came to have a look today & as soon as it started he knew straight away that is was an injector. Its the #1 injector too which is the electrical one. As they tested & checked them all they are going to redo this tomorrow & fix the problem!!!! Man I am so happy as its not going to be a major problem for us!

Bigrig
15th February 2011, 05:58 PM
well the guys came to have a look today & as soon as it started he knew straight away that is was an injector. Its the #1 injector too which is the electrical one. As they tested & checked them all they are going to redo this tomorrow & fix the problem!!!! Man I am so happy as its not going to be a major problem for us!

Good stuff mate - nice to have a win every now and then!!!

Major Black
16th February 2011, 02:02 PM
Great to hear that Kat. Top stuff :thumbup:

You got no idea it was a huge relief! Although took the #1 injector in there today to have it checked again & its a huge flow coming out! So she is buggered! They rung Nissan who advised that they still don't think the electric injectors can be repaired. Got a quote for a new one of $650.00. It floored me, I was shocked that such a small part would be so expensive! Anyways they had seen the look of shock on my face at the mechanics & they gave me a second hand one from their parts department! Fingers crossed this arvo when she is all put back together that we will be back on the road again! A month with out my trol has been a nightmare!