adjustable rockers?

[DragCamaro]

hey everyone, i just got my gn and its got some nasty valvetrain noise, is there anyway to make the stock rockers adjustable? if not what are my options for an aftermarket adjustable valvetrain? it has a 206 cam in it supposidly as well
thanks a lot, Mark

btw: you guys were right, these bastards pull hard!

 

[DailyDrifter]

I dont think there is a way to adjust the stock ones, I would go with T&D's for around $500. Make sure the rockers are the problem before you start throwing money at it. Congrates on the car, they do pull like hell.

 

[turbofabricator]

You have a few options. T&D roller rockers, or Harland Sharps. Very expensive, though, because you will not only need the rockers assemblies, but you will also need either valve covers or valve cover spacers.

Another viable option is to purchase a set of adjustable push rods. They run approx. $125. They work real well, though, they are a bit of a hastle to adjust on the car. You will need two high quality 3/8" open end wrenches to adjust them. Dont use el-cheapo tools to adjust them, or you might round off the adjusting nuts.

The other option is to use shims between the rocker pedistal and the shaft. This will help you determine the exact cause of the lifter/valvetrain noise. Use a .016", .032" 5/16 AN washers to decrease lifter pre-load. Place them between the shaft and pedistal, and torque them down. Start the engine and see if it improves the valvetrain noise. If it doesn't, install the .032" washers and repeat.

It might be a bad lifter or two. REAL common, with a flat tappet cam. You will have to pull the intake and pull each lifter to verify. If the lifters and cam are in good shape, install adjustable push rods before you install the intake back on. It will make your life MUCH easier to adjust the pushrods. You are shooting for .020-.060" pre-load. You can measure the actual preload with a wire feeler gauge. Slide the small hooked end of the feeler gauge between the retainer clip and the lifter piston. By feel, adjust the push rod to zero lash, then add 3/4 turn. (on adjustable pushrods ONLY) If you buy roller rockers, you adjust them 1/2 turn past zero lash.

I use Smith Bros. pushrods. Smith Brothers Pushrods Just give them a call, and they'll send them that day. I have a set of adjustable push rods, if you need them. They are used, but in good condition. $65 shipped in the continental US.

Roller rockers are the best way to go, though.

 

[DragCamaro]

thanks for the help. ill probably end up doing the adjustable pushrods, the shim idea isnt bad either i didnt think of that. im thinking its a bad lifter, i just havent taken it apart yet to verify.

what are my options for lifters?

i may take you up on the pushrods
thanks, Mark

 

[bison]

Verify you have the correct length pushrod before you waste any $. Most likely a junk comp 853 lifter

 

[turbofabricator]

Verify you have the correct length pushrod before you waste any $. Most likely a junk comp 853 lifter

.......IF it has a hydraulic roller. I assumed it was a flat tappet 206/206. I could be wrong, though. If you have a flat tappet going bad, you will need a camshaft, too. I've never had success replacing a lifter in a flat tappet arrangement. If you want to stay flat tappet, go with factory GM lifters-ONLY. Also, pay the extra bucks for the cam to be nitrided, too. If you want to step up to a hydraulic roller (good idea) be prepared for a few lifters to be bad out of the box. (the infamous Comp 853 lifters named above) There is a new kid on the block for Buick roller lifters, though. Morrell. Might be worth trying.
A friend of mine just called Comp about their quality of thier lifters, and the tech stated that he was unaware of any problems with the 853 lifters. My friend said "WHAT!?!?! It's ALL over the internet!!!" He said "I dont check the internet." SO............just be aware that there ARE bad lifters out there in the hydrualic roller world. Not to mention bad flat tappet lifters and poor oil additives, that will KILL a flat tappet cam in short order. Buick valvetrain has always had issues. They just seem impossible to completely cure these days.:frown: I've tried alot of different ways to improve the valvetrain in a Buick. Notched lifter bores, sotchbrite the face of lifters and cam, (to hold oil better on break-in), light breakin springs, different addative concoctions, But nothing seems to solve "all" the problems. Good luck.

 

[DragCamaro]

yea its a hydraulic flat tappet. i was going to go hydraulic roller if it came down to the point of replacing lifters.
206/206 cam is what i was told it has, i dont know if thats 100% true though.
ill take the intake off and check everything out sometime soon, hope its nothing too serious

 

[Just a Six??]

Do like Ken said & get the adjustables first before you tear it down. To set preload a large Paper clip is about 35 thous & thats what I use. bend it & slide it in under the clip thingy & works every time for me.

 

[not a v8]

confused

where is the paper clip/feeler gauge going into/between? also is this with the rocker arm all the way up? (lifter on the base circle of the cam). sorry i am a chevy guy, i ve never done a buick.and my lifters are loud. my buddy sez: is there any oil in this thing?

 

[DragCamaro]

i havent ripped it apart yet. i dont know what its clearing ill find it out later, i have gauges

 

[Just a Six??]

where is the paper clip/feeler gauge going into/between? also is this with the rocker arm all the way up? (lifter on the base circle of the cam). sorry i am a chevy guy, i ve never done a buick.and my lifters are loud. my buddy sez: is there any oil in this thing?

When you take a lifter & apply pressure with a pushrod or whatever the cup goes down. So you want to have it go down to 35 thous preload. When you push down on the cup there is room between cup & top lip of lifter, so measure there with the little end of bent paper clip & set to your 35 thous preload. I know this Explanation SUCKS but just take a lifter & push down the cup & you will see what I mean.

PS: The paper clip has to look like an L shape but the bottom of it will only be maybe 1/8" long to fit inside the lifter with a pushrod in there & then get under the lip.

 

[MSDGN]

First and easiest thing to do is remove the valve covers and either run the motor or just spin it and watch the rockers...just look for any rockers that
aren't moving very much...it could be a lifter but more likely cam lobe going or gone...have seen it many...many times...I refuse to run a flat tappet in these motors anymore...JMO...

 

[not a v8]

adjustment

when setting preload, is the rocker arm up (valve open)or down(valve closed).

 

[pacecarta]

adjust only when on base , pushrod down - valve up (closed)
easy way is just look for other lifter on that cylinder to be up(valve open) and adjust the one thats down (valve closed) .

when using t+d rockers one turn is approx 50 thousandths so loosen let sit a little for lifter cup to rise and then tighten lightly feeling for zero lash than go 1/2- 5/8 turn down (clockwise )and lock it down

there is a list that when at tdc 6 lifters can be adjusted (depends on whether your at tdc compression or tdc exhaust which ones to adjust )and then turn engine one full turn and do the other 6

 

[DragCamaro]

First and easiest thing to do is remove the valve covers and either run the motor or just spin it and watch the rockers...just look for any rockers that
aren't moving very much...it could be a lifter but more likely cam lobe going or gone...have seen it many...many times...I refuse to run a flat tappet in these motors anymore...JMO...

yea i was afraid it was the cam as well. ill get back to you guys when i open it up. like i said it runs fine so i kinda doubted the cam being a problem, but it could just be wearing down slowly.

 

[DragCamaro]

i had oil pan off fixing the last owners mistake, and i looked up at the cam through that opening and it looked pretty good from what i could see.
thing im scared of though is there was a good bit of metal in my oil, i had the valve cover off on one side and everything looked real nice under there, it was very clean and the pushrods looked great. it has some kind of double valve spring in it, im not sure of the brand.
also when i had the pan off i figured out i have JE pistons, what appear to be stock rods that have been rebalanced, and it looks like a stock crank, but it was green... idk what the deal with that was. also has some brand of machined main caps, they have the power 6 logo on the bottom of them, i dont know of the brand either.
im going to open the other side up tomorrow mabe and hope to figure some more stuff out.