[Makie43]

I got my Sierra about a month ago, (Swapped it for a tinnie I wasn't using!) it's an '89 model (In good condition , no rust etc. Done about 160,000km.) which had been left sitting for about twelve months. I took the tank off and disposed of the petrol which was black and thick! Cleaned the carby, gave it an oil change and it runs fine except for a knock/ rattle coming from somewhere, when it's cold it sounds like a diesel but after it warms up it seems ok. I took the tappet cover off and the rocker arms and inside the cover the oil coating seems really thick and dirty?? The noise isn't loud and using the old screwdriver stethoscope method the noise doesn't seem to be coming from the crankcase???? I know it has a leaky gasket where the exhaust pipe connects to the manifold but I don't think that would cause the noise. What do I check next? Put flushing oil through the motor? Or try adjusting the tappets??????

[foolsp33d]

a knock you say.. im going to guess its piston number......3..no 4.. no no 3... yes 3... get a VRS kit and new timing belt, rip the head off, least that way you know A: the head gasket will have been changed, B: its got a new timing belt, and C:.. if its cyl 3

this kinda knock!??

[Makie43]

No it doesn't sound as bad as that thank god!! The only way I can describe it is a mechanical rattle not a deep knock like the video. No miss in motor but it does sound like the rattley knock a diesel has.

[royce]

I would flush the oil again with some propoer flush and put some good oil in and adjust the tappets, they always sound a bit rattly though so if its all in spec jsut learn to enjoy it

[paulv]

foolsp33d, what did you end up doing to fix the knock on that one?

[foolsp33d]

took the engine out and put in a secondhander for 12 months lol.. this one is still sitting under the house yet to be investigated ie: back up parts lol..