I am getting a lifter tick on my fresh rebuilt 350. My builder recommended I run 20w-50 oil in the engine. That is what was put in for the break in and it I still have it in there. I know that is not what is recommended to run from the factory manual and although my engine isn't a completely stock rebuild it is a pretty mild build about 325 horse. It has stock lifters that are not adjustable and I have read that sometimes these engines have been known to have a problem pumping oil up to the lifters. So my question is could this thick oil be the problem here? Is it necessary to run that thick of oil, or should I try running some 10w-30 and see if the tick goes away? My builder said he is willing to take care of the problem whatever it takes but I thought maybe this would be an easy thing to try first. I don't want to drop my car off to him and not get it back for a couple weeks. Any thoughts would be appreciated. And just to be clear we have pin pointed it to a lifter tick and not leaking headers.

 

20W-50 is too thick for this motor. 10W-40 would be better, though straight 30 weight is what you should use for break-in. Did you use any kind of zinc additive or high-zinc oil for cam break-in? Were the lifters pre-lubed before installation? Did you properly prime the oil pump before any new start? Did the machine shop properly set the valve stem heights to factory spec?

 

My builder put the engine together so I assume he did everything correctly. Yes it did have the zinc additive for the cam break in. He also gave me another bottle of the additive for my first oil change. He has built olds motors before and was doing a big block at the same time as he did mine. I am no expert but I thought that seemed like too thick of oil to run. The tick seems to go away as the RPM's go up. Although I am at around 50psi at idle for oil pressure

 

I have a similar issue with my 350 as well. My issue though is with the rockers. I have adjusted them at least three times and after a few miles they start clacking again. I have been told to run a heavier 50 weight oil too because of oil pressure issues. I have noticed that there does not seem to be a lot of oil making its way to the heads when we were adjusting the rockers.

This build was a little more agressive than stock. The engine builder says this is all normal but I'm not buying it.

 

My builder also said mine was a common issue but mine are not adjustable. I have plenty of pressure though, about 50psi at idle

 

You apparently missed my "trust but verify" quote in another thread recently.

 

Agreed. This is not normal. A tick is too much clearance period. Whether it be a collapsed lifter, bad rocker bent push rod or incorrect stem height. That shouldn't/cant be made up with oil viscosity. 20W50 is too thick. 15W40 is about as heavy as one should go on a street driven car in a moderate to hot climate. On a brand new motor 10W30 to 10W40 for break in depending on how tight the clearances are. Never have I run 50 weight on anything for break in period or any other time. That even applies to the 10K & 20K CI engines.

 

I think I understand what your saying Joe, but if I knew how to do this myself I would. Meaning all I can do is trust that he knew what he was doing, not sure how I can verify that? Assuming your talking about the engine specs and not just the oil. Just to be clear there is no sarcasm meant here just wondering what I can do to verify.

 

Sounds like I should just bring it to my builder and let him take care of it. I think I will change the oil first though. Just for my own knowledge what are the issues caused by running too thick of oil in an engine?

 

I'd be leery of an engine builder that told me to run 20-50 in a new engine. My builder told me to use Joe Gibbs straight 30 brake in oil for the first 500 and then change over to 5 or 10-30, I used 10-30 oil in it and it carries 60 PSI with a stock pump. I had a couple of ticks from the valve train on start up when the engine was new, now that it has 2500 on it, it never makes any noise.

 

Ya, after seeing the comments from you guys I am a little confused why he would recommend that? My engine was broken in, but I have only put maybe 10 miles on it after that. Should I change the oil and drive it for a while first to see if it clears up?

 

This comes up a lot due to the large number of Chevy-centric machine shops out there. Since they are used to Chevy's adjustable rockers, few take the time to ensure that the valve tips on Olds heads are set to the factory spec necessary to work with the non-adjustable valvetrain. Of course, this could be caused by a different problem, but this is a common one.

 

Ok, I see what your saying. I think what I will do is change the oil, pull the valve covers and make sure they are torqued correctly and go from there. My builder said he would correct the issue, I just wanted to see if it was something I could maybe take care of so I didn't have to be without my car for a while. My main concern is just that it is taken care of correctly.

 

When he rebuilt the engine, did he replace all the rockers and perches? Were the heads milled? X2 on Joes question, did he cut all the valve stems to the proper length and are they all the same?

I agree with everyone else on the 20-50 oil also.

 

The head work was done to accomodate big block valves, they were not milled. He said the rockers were in great shape so he reused them. Not sure about the perches.

 

If you're going to pull the valve covers, I would also pull the rocker arms and lay a straight edge across the tops of the valve tips. They should all be in line with no gaps.

 

My builder recommended Joe Gibbs 10-30 as well. Only thing I've ever seen using 50 is a control differential on a Sherman tank

 

Not replacing the perches and rockers assy's can lead to your problem.

 

So are you guys saying that even on an older motor with 30-40k miles one shouldn't be using 20w-50? I use it right now on my 69 350 2bl stock and it seems to quiet down the motor quite a bit. Should I go to a 10-40 instead as I may be damaging the motor? not meant to hijack just a query.

 

I have a little lifter noise in my engine also. My guy said he could mill the rocker pivots down a bit and eliminate it. '67 442.

 

Oil which is too thick for the engines designed clearances can have a harder time getting into tight clearances especially on start up when cold or if the engine wasn't built "loose" to handle the thicker oil. It will hamper horse power some too because the rotating assembly has to deal with thicker viscosity. Some will put thicker oil into a higher mileage engine with low oil psi to deceive or just to get more time out of it before it grenades..
If the valve train is not set up correctly it will be nothing but trouble. As many have mentioned if the machinist inst knowledgeable on Olds specific valve trains it will never be right. You could have something else going on so some good trouble shooting will find where the problem is.

 

Yes IMO too thick. Dry starts are the enemy there. 15W40 is as thick as Id go. Again if the engine was built loose specifically for 20W50 then fine, but who does that anymore. That's way old school.

 

Are they all clattering or just one or two? You could just have a bad trunnion or lifter? Trouble shoot before R&R.

 

It is only coming from the passenger side, not sure if its one or two haven't pulled the cover to see yet

 

Figured out the issue last night. Pulled the valve cover and one of the rockers was very sloppy. Turned out my builder had put the wrong length push rod in on one of them. Got the correct one and the tick is gone.

Question on the oil now though, I did do an oil change to 10w-30. I'm at 50 psi pressure at start up, once warmed up to temp the pressure is around 25psi at idle, around 40 when cruising. Does that seem too low? should I run something thicker?

 

"I'm at 50 psi pressure at start up, once warmed up to temp the pressure is around 25psi at idle, around 40 when cruising. Does that seem too low? should I run something thicker?"
In my opinion you're fine with those oil pressures.

 

sounds good, thank you