Hlux knocks at startup

[Yumsylux]

Hey guys,
I've owned my LN106 dual cab for almost 12 months and the last few months. (yes it's slack)
Whenever I start my motor, hot or cold for the first 5 secs or so the oil light stays on and there's a knocking sound that's coming from the motor. Once the oil light goes off the knocking stops. It's only a slight quiet knock but when you know what sounds your car normally makes you do notice it. Does this happen with anyone else's Lux? Is it a big job to fix? I can only think it's building oil pressure at startup, and the oil is probably too thick. I change it every 4500ks and use 15-45 diesel oil. That's good oil right? Thanks guys.

[Yumsylux]

I forgot to mention it's a 2.8 diesel. With nothing done to it except 240,000 kays. Injectors at 200k and pump at 225 when I bought it.

[+dj_hansen+]

I know here in melb mine makes that noise coz its so damn cold and the revs are very low until it starts to warm up... would probably just be low iol pressure for the first minute or so until the internals warm up and the oil gets flowing... also check your glow plugs, they should read ~0.5 ohms resistance if they are working properly, not sure how to check them tho.

Best person to answer this would be dumbdunce, he seems to have answers to any hilux question you could possibly ask

[mechtech]

just a thought, but a few of the cheaper oil filters do not have an anti drain back valve in them, helps with quick delivery when started, i know the ryco oil filters have them, but as i said - just a thought, that is the correct oil, but maybe try an additive like friction proofing (wynns) when your tolerences increase (K's) the thiner oil will take longer to build up pressure, otherwise, as old matie said, glow plugs, could be a cylinder taking a bit longer to fire,, does it idle rough when it knocking?

[BadLux]

yeh mine knocks when its cold... How bad is that???

[high n mighty]

Mine knocks for a few seconds on thicker oil, I put 20-50 in this time as an experiment to stop smoke and some LucasOil. Can't remember it doing it before but I havent had this engine long enough(or driven it long enough) to know if this is its normal behaviour. I know my old engine never done it.

My call is a slow oil pump though but I don't think a few seconds is really going to hurt it in the scheme of things.

[Yumsylux]

I'll try a different oil filter. It is actually a supercheap crapjob. I thought since I'll change it so often what's the difference... I'l go the ryco's next time. The glow plugs do take a while to warm up too. Almost 10 secs so you're right it's probably that too. Yes is does idle rough at the start but it's okay when the oil light goes off. Some reason when i had the injector pump rebuilt the idle was up around 750-800rpm but it's dropped to around 600. It's definately slower but I'm not game enough to mess around with diesel pump. It should be up around 7-800 right? Will that affect it? Thanks for replies too.