How to Set Hydraulic Lifter Lash/Preload VX V6 n/a Ecotec

[Gw33dz]

I've got a sticky lifter or 2 and I've got some new lifters/pushrods on order.

Was just wondering what the general consensus or what a service manual says about setting the preload on the lifters

I know how to start by setting the lash to zero, was just wondering how much more of a turn I should go to set the preload correctly.

I'm thinking 3/4 of a turn extra, but not 100% sure, any help would be greatly appreciated.

 

[vr304]

Your referring to the procedure for adjustable roller rockers, the ecotec runs non adjustable rockers mate you simply torque them to spec (search what torque setting) when that particular valve is on the base circle of the cam so your not opening the valve when you tighten the bolt and get an inaccurate torque setting

 

[losh1971]

You still need to measure preload. To adjust them generally it's done with different length pushrods. If there is too much preload you could shim the rocker chairs I guess.

 

[Immortality]

If they are standard lifters and pushrods then setting them is as simple as fittings em and torquing the rockers to spec. just make sure the push rods and lifters are the same as the ones that come out.

 

[Gw33dz]

I see cheers.

I found the specs in a service manual (for a VT), says:

"Step 1: Rocker Assembly Bolts 11-19nm,

Step 2: Tighten a further 87-93 degree turn"

So I guess i do that when each valve is on the base circle and voila.

If they are standard lifters and pushrods then setting them is as simple as fittings em and torquing the rockers to spec. just make sure the push rods and lifters are the same as the ones that come out.

I'm installing brand new standard lifters and pushrods all round, about half of the old pushrods were worn when i last looked. Just don't want to have to pull the motor apart again.

Should I use loctite on the Rocker Assembly Bolts? (Just seems weird to me how they don't lock)

Should I soak the new lifters in oil before installation?

 

[losh1971]

Personally I would measure preload. I only say that because I had to pull all mine out again when I just bolted them down and torqued them and measure the preload on each one, because after fitting new rockers and rods I had a rattle. There was another young bloke on here who had a similar issue on his VT and he followed the normal directions of bolt them down to spec and away you go. He had a rattle too. If you measure the preload and you develop a rattle or improper running, you know the issue is elsewhere if they all have the right amount of preload.
I'm no expert but I have had trouble before and now take extra precautions. Also did you buy new bolts? I'm pretty sure the factory bolts are single use.

I used Loctite Blue on my rocker bolts. Torque bolts to spec with each cyl on TDC when you tighten them.

 

[Immortality]

Stock rocker bolts are torque to yield and should be replaced once removed. I'd replace with a set of cap screws, our site sponsor MACE can supply these are alternately you can get em from an engineering shop. You can use loctite if you wish.

 

[Gw33dz]

Thanks for the help. Will order some Mace bolts.

 

[Dak]

Yup, as above, there is no "setting" they are none adjustable. If the block hasnt been decked of the heads planed excessively then its just fit and torque the bolts as per the manual. And, yup I always soak new lifters in oil overnight.

 

[Gw33dz]

I used the Mace bolts. They have an allen key head, so i had to hacksaw an allen key and insert it into a socket so that i could use the torque wrench.

The Mace bolts simply tighten to 23ft/lbs (approx. 31nm). I went to 33 to account for the adaptors etc.

I removed the spark plugs so i could turn the crank manually. When i saw a rocker arm at it's peak height, I torqued the bolt on the other arm in the pair, presuming that it would then be on the base circle of the cam.

When i torqued a bolt, i then marked it with a white paint pen and bam!

She's purring like a kitten.

Thanks so much for all the help, i got wheels again, Yeeew!!