Land Rover noises after a day of offroading, Chev engine experts please chime in

[Redlyne_mr2]

Hey guys,
So I have a 98 Discovery with 130K kms and after a day of dirty, dusty offroading I began to noticing a knocking noise as I was driving back from the trail on the dusty access road. As I got onto the highway and got up to speed (65mph) the knock got worse.
For those unfamiliar with the Discovery they use an old 4.0L Buick V8 so it's a relatively simple design.
I got the truck home and checked the oil.
-Oil level was fine
- Engine was REALLLLLY dirty, covered in mud, dust etc.
- Coolant level was fine

The noise appears to be coming from the top of the engine, almost as if it's in the plenum (intake manifold) area.

Could this just be really dirty lifters from sucking in dirty and grime?

Any help is really reallly appreciated.

Thanks gents.

[Alak]

I'd maybe take a drive to the rover shop, vern would know what it is. I could probably take a look since I have the exact same engine (albiet with better fuel injection hahaha).

Could be something, could be nothing. I remember one time I thought my alternator bearing was going. $600 alternator. Turns out it was the $35 pulley next to it.

[dsr7723]

Originally posted by Redlyne_mr2
Hey guys,
So I have a 98 Discovery with 130K kms and after a day of dirty, dusty offroading I began to noticing a knocking noise as I was driving back from the trail on the dusty access road. As I got onto the highway and got up to speed (65mph) the knock got worse.
For those unfamiliar with the Discovery they use an old 4.0L Buick V8 so it's a relatively simple design.
I got the truck home and checked the oil.
-Oil level was fine
- Engine was REALLLLLY dirty, covered in mud, dust etc.
- Coolant level was fine

The noise appears to be coming from the top of the engine, almost as if it's in the plenum (intake manifold) area.

Could this just be really dirty lifters from sucking in dirty and grime?

Any help is really reallly appreciated.

Thanks gents.

Could very well be sticking lifters, all older V8's get that every now and again when they get worked. Even if you're not due, I'd start with a good flush and oil change and take it from there.

[Redlyne_mr2]

thanks guys, yah well start with an atf flush, maybe a sea foam. it could even be an alternator noise or pulley bearing but well see. Damn knocks.

[Redlyne_mr2]

So ATF flush did it. Basically drained all oil, added 6 quartz of atf. Idles truck for 10 minutes then let cool for 5. Repeated this 3 times, drained atf added new oil and filter. Truck runs like new... !

[Alak]

ATF has some powerful detergents. I have a slight tick, I might give it a go for the heck of it.

[turbotrip]

What is this atf flush you folks speak of?

[sneek]

Originally posted by turbotrip
What is this atf flush you folks speak of?

Some people like to use ATF as a detergent in the oil. In this case Redlyne flushed completely with ATF and idled the car a few times?

It is an old school trick to run say 4L of oil + 1 L ATF if your vehicle needed 5L and you needed some sort of engine cleaning.

[PulsePro]

Disco 1 or Disco 2? Both of them were in 98

[Alak]

Both of them were in 99. Accually.


He has a D1. 98 was all D1.