Lifter adjustment

[knockdolian]

Hi all, hope everybody is well and coping during these interesting times. The forum seems very quiet at the moment so thought I’d try and start a chat. I asked some time ago about identifying my engine. I couldn’t find anything that looked like an engine number. Having now pulled the trike apart for some maintenance I’ve realised why. There is a casting number only. I didn’t know there was such a thing as a crate engine and assumed the early stuff would have come with reconditioned engines !! Anyway to my question. It has a ZZ4 roller cam. Am I right in assuming that if it has a roller cam it has roller lifters. If so, is the adjustment of the lifters the same as for flat lifters. I have no tappet noise but would like to A check and B learn something. Thanks all .

[Paul H]

OK, lets start with roller lifters. The roller part is on the bottom of the lifter and in our case it is a hydraulic roller.
As with flat tappets and roller, solid tappets and hydraulic
are both available. The fact that you state no noise
would tell us that you have hydraulic roller lifters.
Solid lifters, flat or rollers, would be noisy, You could hear them tapping and they require routine adjusting. There are also roller rockers where you do the lifter adjusting.

Paul H

[knockdolian]

Hi Paul. Hope your well. I think there is a brake down in trans Atlantic translation. What I think I know.
There are solid lifters that you set a gap at the tappets (rockers) like British classic cars
Hydraulic lifters as in our engines can be flat at the contact point with the cam or have a roller. These have no gap. They are pre loaded. How am I doing so far ?

[knockdolian]

I. Know I have hydraulic lifters. My question really is do hydraulic lifters need periodic check and adjustment and would that adjustment be the same for roller lifters and flat. Thanks

[Paul H]

That OK, I may have the wrong name of some of the items. Solids are set with a feeler gauge as you say.
Hydraulics are set with a preload. If and when the Hydraulic lifters are pumped up you screw down the rocker
to zero lass then 1/4 or 1/2 turn more to preload the
lifter. This is all to allow for heat expansion of the block and head...

Paul H

[knockdolian]

Thanks Paul, what is the difference between a 1/4 and a 1/2 turn. Please don't say 1/4 !!! Most of the Utube videos show remove free play (lash) then as you say 1/4 or 1/2 depending on who you are watching. One video mentions that the procedure for rollers is a bit different to non rollers. If my engine has ZZ4 roller cam does that mean I would have roller lifters. Hope that makes a bit more sense. Thanks again

[V8Bikers]

Under normal circumstances the hydraulic lifters do not need adjustment.

[knockdolian]

Thanks Bill, that’s just the answer I was looking for !!!

[Paul H]

Yes, the ZZ4 has hydraulic roller lifters and as Bill
said they usually don't need adjusting...

Paul H

[knockdolian]

Thanks that’s good enough for me I’ll leave well alone.

[Orlando606VetteTrike]

Hydraulic lifters whether flat or roller only require an adjustment when assembling the motor, cam change, lifter change, rocker change, etc. Once that initial adjustment has been made, you no longer need to worry about checking. Beauty of hyd lifters compared to solids.

[knockdolian]

Thanks all. That’s what I wanted to hear. While in lockdown I’m making an effort to tidy the poor old as she’s now 25 years old. While the rockers are off and the headers I want to check the torque of the head bolts. I now know I have 193 heads. I have read the internet and can’t find a definitive answer on head bolt torque. Now while people may say again after 25 years this won’t be necessary it is useful information to have. Thanks

[Orlando606VetteTrike]

zz4-engine-long-block-installation-guide-24502609.pdf

(497.99 KiB) Downloaded 202 times

[knockdolian]

Thanks for that Orlando. Hoover my engine isn’t ZZ4. This is. What I’ve been trying to find out . Is the torque setting the same for aluminium heads as steel heads ?
Thanks again

[Orlando606VetteTrike]

[knockdolian]

Annotation 2020-04-30 071157.jpg

That’s spot on mate. Thanks for that. Your first image says for ZZ4. Am I right in thinking they are Aluminum heads. Hope you can see how confusing a complete question can be. Thanks again
Stay safe.

[Orlando606VetteTrike]

Take a picture of your engine/heads and post it.

[knockdolian]

I have identified the heads as 193 heads

[Orlando606VetteTrike]

The casting number of those heads ends in 083, and yes they have 1.94/1.50 inch dia valves. The chamber is identical to the 350 iron heads that has casting suffix 193. The 083 were used in Fcars and the 193s were used in light- and medium-trucks and fullsize passenger cars. The 193s use a swirl ramp under the intake valve so they flow slightly less that the 083s, but the 193s flow better on the exh side. The 083 flows approx 185 cfm intake and 120 cfm exh. The 193 flows 175-180 cfm intake and 140-145 cfm exh. The 193 was called a fast burn head by GM back in the mid 1980s, because the swirl induced demanded less ignition timing due to the faster burn front convection.

The alum version of the 083s was used in the Vette only. When they first issued, they didn't flow any better on the intake side but did flow better on the exhaust. That head, 113 casting suffix, has been steadily improved since so now they flow very well out of the box for both int and exh.

[knockdolian]

Thanks Orlando, that is a lot of very useful information. More than I could find on the net. The casting numbers on my heads do finish 193. Just been doing some work on the trike while I’m in lockdown and just trying to find out as much information as I can.
Thanks a lot.

[Orlando606VetteTrike]

My pleasure.