I have a 2006 Buick Lucerne with the Northstar V8 122,000 miles. Lately after it starts, there is a ticking like a lifter noise, after it warms up a little it quiets down. Question for any Northstar tech here is, do these engines have any adjustment for the valve clearance if this is a lifter problem. If not a lifter, what other noise could this be? I know nothing about these engines except I love the car and this thing is really a hot rod in disguise.

 

The N* is overhead cam and doesn't use lifters in the conventional sense. It has roller rockers that ride on the cams and actuate the valves. The pivot end of each rocker sits on a hydraulically-actuated lash adjuster. The lash adjuster functions similarly to a hydraulic lifter in that it uses oil pressure to take out clearance in the valvetrain, however it is fixed in the head and does not move up and down like a lifter. Like a hydraulic lifter, the lash adjusters can get gummed up, causing the ticking. The rockers and lash adjusters can be replaced without removing the cams. There are videos on the web that show how to do this. Here is one comprehensive how-to article.

 

Thanks Joe, I think I will just let it click for the short time it takes for the engine to warm up. With 122k miles there might be something else show up. Not something I can't do, just don't want to get into it now. Unless more start making noise, I can live with just one.

 

are you doing the recommended northstar cleanout procedure? climb on a highway at 30mph, cobb it and hold it to 75. (only takes a few seconds so dont blink) repeat. they say it seems to cure a lot of ills and it is more fun than a barrel of monkeys.

(PS: dont discount excessive wrist pin clearance when cold as a source for the tapping.)

 

I do this nearly every time I drive it. Like I said the car is a hot rod in disguise. Surprises lots of new Mustangs and Camaros by staying up with them.

 

they are meant to open up they (other owners) say. I dont open mine up so much as I do the down hill manual downshifts to hold back because of the injector shutoff program - almost feels like a jake.

anyways, these motors are full floaters and if after start the tap comes in and goes away when warmer or revved up - suspect wrist pin clearance issues. gm managed to issue a couple many dozen tsbs for this on most families.

SHLA issues can be cleaned up, and they start immediately on start, no delay, but very very rare - so how does yours come in? immediately, as you are starting it?

how is your oil consumption?

 

Ticking is immediate, Starts as soon as engine fires. Goes away pretty quickly. Oil consumption is nil except for minor leaks. I understand these are known for their leaking issues after lots of miles. I think mine are coming from the valve covers. There are no hills to do the jake braking operation around here.