Hydraulic valve tick when engine is cold

[Bigtrain]

Deve,

Had the 235 out of my 58 Apache (T/F trespasser) O/H last summer by a reputable local machine shop. The shop assembled the engine and set the valves. Had them install hydraulic lifters thinking them to be an upgrade and would quite the engine down. The engine runs great and is a heck of a lot quieter.

I have 1200 miles on the O/H now and I noticed the last two times I've started it, when the engine was cold, it has a slight tick coming from the valve train. Once the engines is warm, the tick goes away.

I reviewed your note on Jeff's hydraulic valve adjustment procedure where you state that machine work has to be completed when changing from solid lifters to the hydraulic lifters for them to work correctly. What does this machine work consist of? I'd like to have some insight on what exactly needed to be done before I call the machine shop. My guess is the shop did the required machine work and that the valve train just needs a little adjustment after break in.

Have you had to adjust hydraulic valves on any of your engines after break in?

Thanks

[Deve]

I will be corrected if I am wrong guys.. I have an ace in the hole who reads every post and corrects me, so I will tell you what I think...

The hydraulic engine differs from the solid lifter engine in that the Hydraulic engine block is drilled especially for pumping oil into the hydraulic lifters. When getting your machine work done, and you prefer hydraulic lifters, ask the machine shop to do the proper machining for this. Now if all you do is just put Hydraulic lifters into your 235 without any machining, it very well may work anyway! This has to do with enough oil being in the vicinity to keep the lifters pumped up with oil. This is not ideal because every now and then you may hear a ticking sound until the lifter is fully filled with oil. Ask your machine shop if they can drill the proper holes for Hydraulics. I am sure they can. They did it to my 261. I am a hydraulic fan. I do not get any machine work done that doesn't include that modification. Once you go to hydraulics and hear that beautiful sewing machine sound of pure QUIET, you will never go back. Silence is a beautiful thing!

But there is more! Hydraulic lifters provide a cushion that is much easier on the push rods, rockers and rocker shaft. You will find less bent rods, less misery with a Hydraulic lifter engine. Everything is much nicer running as a result. As far as adjusting after breakin, YES, that is a very good idea. If that ticking goes away, you win! To tell if your engine is a native hydraulic engine, usually from a car, write down all of the numbers.. on the flat of the Distributor, above the Starter, just below and to the right of the Distributor and then go to the Casting Number Database to see if your block is already drilled for Hydraulics. Car engines with Powerglide transmission had hydraulic lifters. All original truck engines had solids. There is a VERY slight horsepower loss with hydraulics. But none of you who run a 235 or 261 would notice it, but you WILL notice the noise!

[Bigtrain]

Thank you for your prompt response. That's why I enjoy this site.

From what I can tell from the casting numbers, it's the original truck engine, hence solid lifters. Doing some body work over the winter so I won't get to the valve adjustment for a while. I'll get back to you with some feedback when I do.

Thanks again Deve!

[Pre68Dave]

A few things,
Numbers are to the left(toward rear of engine) of distributor.
All 235's starting in 1958 are drilled to supply oil to hydraulic lifters.
I would suggest reading my blog post about 235 hydraulic lifters, especially near the bottom.

[Bigtrain]

Took a look at your blog. Sounds like I have a new lifter that needs a little more time to wear in. Thank you!

[Deve]

And there ya go folks! My GREAT friend Dave knows this stuff so well, and please heed his advice every time! Dave, is that also true for the 58-62 261? The Cam is different for hydraulics vs solids?

[Pre68Dave]

261 are a strange breed, I have not been able to confirm when they started drilling them, most likely in 1959.
Hydraulic cams have equal lift on both intake and exhaust lobes, solids are taller on the exhaust to makeup for the extra valve lash.
You stated above that solid cam engines had more horsepower, I am pretty sure it is the other way.

[Deve]

What I like about these encounters on THIS site is, questions are asked and answered with clarity. It just doesn't get better than this. Thanks again Dave!

[mfahrbach]

I have a 1958 261. I am assuming if it was originally drilled for hydraulic lifters, I would have hydraulic lifters, which I don't. The engine was harvested out of a farm wheat truck. Is disassembly the only way to determine whether it was drilled for hydraulics?

[Deve]

No domestic 261 had hydraulic lifters in them. But I had my machine shop give me hydraulic lifters and hydraulic cam. What I do NOT know for sure is when GM drilled the 58-62 235 engines for both kinds, did they also drill the 261's? My 261 has been sitting here for over 10 years and I do not remember for sure if I had it specially drilled for hydraulics. The engine runs great and its very quiet. Oil Pressure is great. So since my 261 is a 1964 replacement block, I cannot speak for 58-62 261s. Anyone have any thoughts? Since Mike's 261 IS 1958-1962, I wonder if it is already set up. Still have to tear it completely down since the Cams are different.