Periodic loud ticking immediately after oil change M50

[rob101]

could be some sludge. maybe run an oil flush just before your next change. thats what I plan on doing.
Jon you mentioned using 10W-50, do you find that otherwise you get valve train noise on start up if you use lower than 10W for the winter grade.

Mine has sounded like a diesel on warm up when using 5W oils for quite a while.

[repenttokyo]

It could be sludge. I think the previous owner was running 5 or 10w30. The oil I took out of the motor was a bit blacker than I would have liked when 5w40 was put in the second time. Perhaps the 40 cleared out some of the sludge that was thickening things up.

[rob101]

It could be sludge. I think the previous owner was running 5 or 10w30. The oil I took out of the motor was a bit blacker than I would have liked when 5w40 was put in the second time. Perhaps the 40 cleared out some of the sludge that was thickening things up.

most likely, what could have happened is.

sludged oil system resistance has a high resistance to pumping and thus the higher viscosity is needed to maintain a higher pressure to get enough flow of oil into the lifters.

*puts in quality 40 weight less viscosity and less oil pressure (hence initial ticking because not enough pressure IF the system has the sludged resistance). BUT has new detergents which break up the sludge gradually. now less resistance means less pressure needed to get enough flow to pump up the lifters. so now 40 weigh is A-okay.

[ryan roopnarine]

running 5/10w30, thrusting up to 10w40 diesel when i run out of the aforementioned here in the oppressive florida sun and 90% humidity. high mileage m50. 30 weight shouldn't make it do anything, and ontario doesn't get that (relatively speaking) hot. sounds like something got flushed out of its hidey hole and needs to get cleaned out.

[repenttokyo]

ticking is coming back every once in a while. I am going to try a different weight of oil. I can't located 15w50 in Montreal. Would 5w50 be an acceptable substitute? Also, which would be better for a very cold climate (-40): 15w50 or 5w50 ?

[ryan roopnarine]

you need to clean it out first before you put new expensive oil in there and get your heart broken. if you change the oil yourself, try doing some 1600km or less oil changes on the cheapest xw40 or 50 weight that you are comfortable putting in there. i'd say try the 15w40 diesel oil for short bursts. if that doesn't fix it, i'd try to find a reeeall trusted chemical and clean it out. ticking hurts your car a great deal. stopgap measures that will only drown out the ticking or "fix" the problem with pressure are not the things you want to try initially.

[mikeythekidd]

Did ya check the dipstick? Not everyone looks up the crankase capicity on every car. The guy could've stuck 5 Qts. in there and called it good. I would think a Qt. low would cause the racket.

[repenttokyo]

dipstick was good, checked it twice after the oil was initially added and once yesterday.

[repenttokyo]

Could my oil pump be on the way out?

[ryan roopnarine]

as someone that ends up changing the oil on their m50 every six weeks (used atleast 4 cases of 40+30 wt oil in the e34 last year), i'd say no, your oil pump is probably not going out. either the fancy pants synthetic dislodged stuff that is now blocking a passage, or you had a gradual build up that required relatively thin 30 or 40 weight oil to "get past" and get into the places that needed lubrication. the timing of the tick with your oil change is too suspicious to be co-incidental. clean with 30+40 changed very often, chemical if you desire/are willing to risk, then seek out a fatter oil.