If lucas is supposed to thicken up the oil than why does my engine have a slight knock at idle? I'm using castrol 10w30 oil. I put in 1 quart lucas and 4 quarts oil. It used to just knock on a cold start but now it knocks all the time its not a bad knock but you can hear it from out side the car. The knock goes away after the engine revs higher than 2,000 RPM. should I change the oil and just use 10w30 oil?. The strange thing is that my oil pressure is a little bit higher and the engine hardly knocks from a cold start where as before it would knock for sevral seconds and it would be a little louder.
2007-09-25 11:45:31 · 6 answers · asked by CAPTAIN GENIUS !! 5 in Cars & Transportation ➔ Maintenance & Repairs
The engine is a 1993 pontiac 3.1L V6 with 163,000 miles. the knock is fast but it sounds like a light knock I dont think is a rod knock. the knock gets faster with engine speed and goes away after 2,000 rpm.
2007-09-25 12:02:10 · update #1
th knock is coming from the bottom of the engine.
2007-09-25 12:02:59 · update #2
I do not use that junk for nothing in the world. I use the recomended by manufacturer the 5W30 weight on Synthetic. That is all about it. The knocking could be the ignition is not advancing, bad antiknock sensor, or even a bad O2 sensor. The thing is, it could be a timing or a lean running issue. Get it to a diagnostic machine for a troubleshoot.
The oil the thicker the worst.
Oils do...
Cool : Carries heat from parts
Preserve: Prevent rust and keep clean the engine
Cushion: Creates a barrier for parts to ride and absorbs loads
Seal: Seals around bearings and piston rings
Lubricates: Keep the friction to a minimum
If you use thicker oil it will not flow as easy as thiner will do and the engine will "run dry" when is cold, overheating components and creating gunk due to break down of the oil due to heat.
Too thin will not have enough time to soak up the heat from parts since it moves too fast and will not seal properly, cushion can not be made and parts will suffer from loads.
Also on a Knocking issue on GM V6s
On my 94 Grand Prix was the coils. I changed Plugs, Cables and the 3 coils that seats by the manifold. That cured the problem. I believe is #3 piston plug. If you remove the plug from the coil it might be rusted. If you power break the engine, rev it on Drive with the brake applied it will start to miss fire. That was my issue on my SFI 3.1 V6
It quits misfiring when you pump the throttle. At steady speed start to buck.
Also could be dirty injectors.
2007-09-25 12:03:48 · answer #1 · answered by spammer 6 · 0⤊ 3⤋
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RE:
Lucas oil stabilizer question.?
If lucas is supposed to thicken up the oil than why does my engine have a slight knock at idle? I'm using castrol 10w30 oil. I put in 1 quart lucas and 4 quarts oil. It used to just knock on a cold start but now it knocks all the time its not a bad knock but you can hear it from out side the...
2015-08-10 19:47:21 · answer #2 · answered by Lelah 1 · 0⤊ 0⤋
I have no idea what were working on here. Year make model miles engine size ETC. Any play in pistons bearings can cause knock. Cold knock that gets less might be piston slap speed of knock where it is the loudest. top of motor or bottom. Does the knock go away when a spark plug wire is removed or coil is disconnected? Yahoo Answer mechanics are ready to help. Lucas oil treatment is good stuff. Sounds like you might be in for some serious diagnosis and future engine replacement. More info please!
2007-09-25 11:53:29 · answer #3 · answered by John Paul 7 · 2⤊ 0⤋
Lucas oil treatment stays on parts when the engine is turned off. It eliminates friction on cold starts.
I had the same problem with a minivan and it spun a rod bearing.
It sounds like your car is headed down the same road.
Try a 20W50 oil and change it every 2000 miles.
Cold weather you should use 10W40.
Keep the Lucas in it it can only help.
2007-09-25 11:59:34 · answer #4 · answered by CARL B 4 · 1⤊ 0⤋
O.K your oil pressure is now higher and the knock is less. I hate to break it to you but you have a main bearing that is going bad. The reason it gets quiet if you rev it over 2000 r.p.m is ..the oil pressure goes up higher. The thicker oil has reduced the knock at start up but it hasnt solved your problem.
2007-09-25 12:02:15 · answer #5 · answered by Anonymous · 1⤊ 0⤋
The 3.1 is noted for piston slap, mine has done it since I got it used at 54,000 miles and now has 144,000 and is still running strong and sounds the same as the day I got it.
2007-09-25 12:16:08 · answer #6 · answered by mister ss 7 · 0⤊ 0⤋