3.5 litre cylinder

[MoodyBlue]

Any one agree or disagree that if the 3.5 litre motor is overheated that they are liable to loosen a cylinder liner?

Mine is currently rattling like loose tappets but the rattle is very throttle sensitive.

Have been told that it most likely has a loose cylinder liner that is now clicking up and down?

Cheers
Jeff

[Blknight.aus]

yes and no...

not likely in a brand new motor...

given that they havent made one for ages.

yes, over heating it can loosen the liners as can prolonged full load operation

[mike 90 RR]

Just a thought ...
Another part to look at is a worn rocker

Mike

[RoverP6B]

If a liner is going to move, the time when the noise will be most noticable is when the engine is cold and first started. Once up to temperature, the block expansion will hold the liner still and the noise will no longer be evident.

I would lean towards worn lifters / rocker assembly as being the most likely cause.

Ron.

[barney]

sounds like pinging to me.
get your timing checked.
once the sleeve slips, it stays where it ends up, it doesn't bounce up and down even when cold.

[MoodyBlue]

Ron,
Cam, Lifters, and rockers & shafts were all brand new 20,000k ago. I have had the rocker covers off and checked all including bolt torques).

I have got the motor bloody hot twice over the last 12 months through water pump corrosion.

Definitely not pinging, and much louder and more serious rattle than pinging.

I have bought another block off E-Bay and plan to transfer all parts into that.

Will be pulling off the suspect side head first though,

Many Thanks
Jeff

[mike 90 RR]

Ron,
Cam, Lifters, and rockers & shafts were all brand new 20,000k ago. I have had the rocker covers off and checked all including bolt torques).


Definitely not pinging, and much louder and more serious rattle than pinging.



On the Suspect head side ..... ... Start motor .... USING a hose for listening to your ear ... Identify the position of the rattle




Take the rocker cover off.....

I'm still going for a dud rocker .... Have a real GOOD look at the depth of the (push rod) ball sitting in the hollow of the rocker // (Compare it to the others)

Mike
:)

[RoverP6B]

Hello Jeff,

Were the parts that you used, cam, lifters, rockers and shafts genuine Land Rover items or Britpart pattern parts?

I have heard of the latter failing in a very short space of time, with the distance that you have covered since fitment being more than adequate.

Ron.

[p38arover]

If a liner is going to move, the time when the noise will be most noticable is when the engine is cold and first started. Once up to temperature, the block expansion will hold the liner still and the noise will no longer be evident.

The other way around. Aluminium expands at a great rate than steel thus expands away from the liner.

A hole in a block increases in diameter when hot, not the other way around.

[PhilipA]

X2.
I didn't want to dispell dreams.
Also IMHO the sleeves do move when hot and the movement up to the head and down to the ledge is what makes the noise.
The gasket does not cover the sleeve so there is 30 thou or so to move plus the distance down on a composite gasket engine.
Regards Philip A

[Jhonno]

Hi Jeff

Had the same symptoms a few years ago in my old 2door with a 4.4 in it, after much searching isolated it to No5.

Found on close inspection to have a 2thou gap between the liner and block adjacent to the rear inner head bolt drilling on No5.:eek: Don't Know the cause but suspect it could have been a combination of oversize boring to fit flat top holden pistons and block corrsion or just plain material fatigue,:o there was no evidence of vertical liner movement, didn't cut the block to check the corrosion theory

JML

[p38arover]

If a liner is going to move, the time when the noise will be most noticable is when the engine is cold and first started. Once up to temperature, the block expansion will hold the liner still and the noise will no longer be evident.

The aluminium block expands at a faster rate than the iron cylinders so it loosens off the liner when hot, not the other way around.

I don't think the 3.5 is prone to having loose cylinders as the block is a lot thicker in the walls than the 3.9/4.0/4.6.

[PhilipA]

Yes AFAIK the tension of the sleeve is lost usually when the block cracks behind it. That is why water comes out.

The 3.5 does not have such a problem as the block is thicker behind the sleeves.

It has also been proposed that the stretch bolts used on 4.0 and 4.6 put much more tension on the block and may contribute to the problem.

Regards Philip A

[justinc]

I have heard of 3.5's in early P6B's slipping liners, not common though but has been known to happen, AFAIR they were Hi comp engines, 9.25:1 and 10.25:1.

I have never had or seen a low comp 8.13:1 3.5 do this.

JC

[classic84]

Hate to be the bearer of bad news. I have 3.5 and on two occasions have liners work loose. currently have to decide what to do as the last rebuild was only 70,000km ago. Liners don't move when cold by the way, only after some 10-15km to full temp. I spent zillions on temp control; radiators, water pump,electric fans after the last rebuild. Engine runs at 80-85degC, below 80 the liner doesn't move. And yes, they do move up and down, hence the quite loud banging that occurs! I don't tow anything either. If I get this re-built I will get top hat liners installed!

[bee utey]

Hate to be the bearer of bad news. I have 3.5 and on two occasions have liners work loose. currently have to decide what to do as the last rebuild was only 70,000km ago. Liners don't move when cold by the way, only after some 10-15km to full temp. I spent zillions on temp control; radiators, water pump,electric fans after the last rebuild. Engine runs at 80-85degC, below 80 the liner doesn't move. And yes, they do move up and down, hence the quite loud banging that occurs! I don't tow anything either. If I get this re-built I will get top hat liners installed!

You are right, it does happen, albeit rarely. I would consider another second hand engine/block, there are many around. The risk would be small for you to be hit again, and far cheaper. If you go top hats you might as well do it to a 3.9/4.6 and make your spend worthwhile.