Outer Limits 4x4 Board

G'day all,

Was look for the oil leak on my Rangie yesterday and noticed the inlet manifold gasket that covers the top of the cam and push rods was not sitting down in the nice curve shape it was when I fitted it. It had been pushed up and hit the bottom of the inlet manifold. I assume it has cracked the tin and thats why there is oil coming out and running down both ways. I have seen this happen on another Rover V8 before. Is this common? I don't want to replace it and have it happen again, any idea's why it would do this??

My thought was crank case pressure build up due to blocked PCV or flame trap?? It's a 1988 3.5L EFI

Probably sump backfire. Gas?
Maybe excessively rich mixture if petrol.
Didn't you hear it?
Could be blocked flame trap, as they do not have a PCV.But in my experience there is not enough pressure for that to happen.
Also maybe blocked hose stub from crankcase ventilation at the throttle body.
But I reckon that it is usually a sump backfire that causes this.
Long shot is a blown headgasket into the valley.
Regards Philip A

^^^^^^agree completely

Also seen excessive blow by pop the valley cover up

Nope didn't hear it

motor doesn't seem to have any real blow by.

head gaskets were done only 3k ago with the inlet manifold.

Well the motor doesn't run rich at all, although I did have the cold start injecter hooked up to begin with and it may have overfueled it long enough to cause this to happen??

G`day

Is this the car that went to melbourne not long back ?

When you did the heads did you fit and torque to specs the 8 lower head bolts ( 4 per side ) ?

Did you see much gunk inside it when the valley was off ?

The oil leak is also relieving any pressure so hard to suss out unless it can be blocked , without replacing the gasket .

Give it a comp test , see if any are down ?

When you replace the inlet gasket if the problem is gaskets head you will be able to see the new one going up and down , like lungs breathing .

If it leaks oil again after the new gasket or raises the gasket and you found nothing with the head gaskets , i`d look at the crankcase vent .

Most of the vent system is obvious as far as cleaning it out .

There is one spot that requires removal of a welsh plug and use of a drill bit to clear the port but no point explaining unless you work out it`s the vent system .

Go with the sump ignition if you`re happy with that but the other 2 are common .

Cheers

yeah this is the one that went to melbourne.

yeah I torqued all the head bolts including the 4 down each side at the lowest point.

Car had been sitting for ages so there was some build up dust. But i cleaned this off.

Yeah thats what i figured. will do a comp test but the Rangie is running the best it has been, doesn't miss a beat and has heaps of power for a 3.5

GURU wrote:yeah this is the one that went to melbourne.

yeah I torqued all the head bolts including the 4 down each side at the lowest point.

Car had been sitting for ages so there was some build up dust. But i cleaned this off.

Yeah thats what i figured. will do a comp test but the Rangie is running the best it has been, doesn't miss a beat and has heaps of power for a 3.5

Doesn't mean it doesn't have blow by

most engines perform there best as there about to go pop....

G`day

Reasons for the Qs

The 4 lower bolts if tensioned to spec can be the cause of pressure leaking into the valley .

Common to pull the head off and see on the upper edge of the head gasket where the pressure is making it`s way , there will be carbony/varnish looking dark stuff that tells .

Were the ones replaced like that ?

They can sort of rooster the head a little but it doesnt` need much .

I`d expect it`s one of the reasons they are deleted in the cross bolted engines .

The usual thing to do is either leave them out all together or only set them at about 15 ft/ibs .

After a nice long run like it did the problem is more likely to surface .

Possibly a leak down test may tell something but probably just using a compressor if you have one that will put in enough pressure may find something .

Listen in all the relevant places for air escaping .

If that is the problem .

I`d probably investigate the head gaskets as best i could , clean all of the crankcase vent system then put a new or seal the inlet gasket .

I quess a crankcase ignition is possible but if the engines is half decent it would be hard pressed to find an ignition source and if the vent systems working any unwanted vapours should be purged .

Cheers