Thread: Replacing big end bearing on 4ltr V8 series 2

Originally Posted by skymack

Could someone give me any indercation to how long it would take from start to finish replacing big end bearings V8 4 ltr series 2 - small knocking noise when starting in the morning - 5 seconds then goes away

If the noise goes what makes you think its big ends? Sounds more like a slipped liner.

Re the big ends change out i recon you could do it in a weekend comfortably

Hi lucus,

Why big end bearing? oil could have leaked past the bearing over night? then once the preasure builds up and tempeture it goes away?

Originally Posted by skymack

Could someone give me any indercation to how long it would take from start to finish replacing big end bearings V8 4 ltr series 2 - small knocking noise when starting in the morning - 5 seconds then goes away

The oil will bleed out overnight in a bearing with healthy clearance. A worn bearing normally knocks worse when the eng is hot and the oil thins out.
A worn bearing in my experience will continue to knock not disappear after a few seconds.

It could also possibly be camshaft end float, although I think that problem was fixed by Disco II.

I've done it and it's an absolute pain setting the big end bearing torque from under the car unless you have the correct tool - an angle torque wrench. The cheap option of an angle meter is almost impossible to use. I've tried, even with the car on a hoist so I wasn't working on my back.

This is hopeless:



You need one of these - a Snap-On Techangle wrench:

wonder if its not a bit of tappet noise, not having played with the 4.0 but assuming its essentially a massaged 3.9 what if the oils lost some of its visocitsy and is leaking out of the tappets on start ups after sitting?
oh and

bugger the torque angle wrench...

grab a printer that can print onto sticky labels and print out a graduated circle in the size that you need.

to work that out just make an inner circle 1-2mm bigger in diameter than the point to point width of the bolt and then the outside cirlce whatever size you can fit out past the bolt head.

to use it tighten your bolt to the preset torque with the torque wrench and then put the sticky label over bolt head,(preferabley with the start point lined up with a point on the bolt) then paint the side of your socket and once dry scribe a line into the paint that lines up with one of the internal points on the socket.

now all you do is put on the big ass breaker bar and pull the socket around till it lines up with the stop mark on your template.

as most angles are in multiples of 30 degrees you dont even really need the template once your used to doing it. a bihex socket is offset at 30 degrees per "tooth" and a bolt at 60 degrees. count it around on the points of the bolt and then if you need the extra 30 degress offset the socket one position. on the face that the bolt will pull against mark out the start point and the destination point in paint and then with the painted and scribed socket scratch the start point then remove and replace the socket in the finish position.. Remember to hold the socket in the direction of tightening when you make the marks as you can be off by a couple of degrees due to the slop in the socket.

Another tip is to set your ratchet to undo and then with a bar on it that makes it the same length as your breaker bar (or whatever else your planning to use to tighten the bolt) ratchet it around in the direction of tightening so you can check that you can get a good pull and full turn on the socket. nothing worse than having to stop mid pull becuase the bar is fouling on something....

I think it's tappet noise.
I have rarely heard of a Rover V8 having big end noise unless it has been run out of oil or done several 100K.
The answer to tappet noise is often to change the oil filter, as even factory filters sometimes come with a faulty drain back valve. This allows the oil in the tappets and passages to run back to the sump, so the tappets rattle until oil fills them.
The 4.0 tappet gear is identical to the 3.9.
Regards Philip A

Originally Posted by PhilipA

I think it's tappet noise.
I have rarely heard of a Rover V8 having big end noise unless it has been run out of oil or done several 100K.
The answer to tappet noise is often to change the oil filter, as even factory filters sometimes come with a faulty drain back valve. This allows the oil in the tappets and passages to run back to the sump, so the tappets rattle until oil fills them.
The 4.0 tappet gear is identical to the 3.9.
Regards Philip A

What filter do you recommend Phillip?