1946-1949 Lifter adjustment

[49 Caddy]

  I am in the process of re-assembling the heads on my 49 Cadillac 331 motor.  Is there no adjustment of the rockers for this engine? 

[Rossoroo]

No, the hydraulic lifters do all of that

[Jay Friedman]

No, the hydraulic lifters do all of that

Nonetheless, in certain cases where a '49 cylinder head has been milled to take surface off, the push rods in effect can become too long and thereby cause one or more rocker arms to not allow their valves to completely close.  When this occurs the solution is to install sufficiently thick washers under the brackets which support the rocker arms, thus "shortening" the push rods so the valves will close.  This happened to my own '49's motor when it was last rebuilt and it could be said that it was "sort of an adjustment".

[49 Caddy]

  Thanks for the responses.  Should I fill the new lifters with oil or just soak them in oil for a couple of days?  Also,  I did not install the felt washer on the oil pick-up like I should have.  Do I need to pull the oil pan and install it or is it not that big a deal?  Thanks in Advance for the responses.

[Jay Friedman]

Thanks for the responses.  Should I fill the new lifters with oil or just soak them in oil for a couple of days?  Also,  I did not install the felt washer on the oil pick-up like I should have.  Do I need to pull the oil pan and install it or is it not that big a deal?  Thanks in Advance for the responses.

After installing the lifters in their place in the block and before installing the push rods, I usually just put a few drops of oil in the cup-like area on the top of the lifters where the push rod sits. You could soak them in oil a few days, too.

I've never not installed the felt washer on the oil pick-up, so don't know what would happen without it.

[Roger Zimmermann]

I've never not installed the felt washer on the oil pick-up, so don't know what would happen without it.

Loss of suction, resulting in a low oil pressure.

[49 Caddy]

  Thanks again for the responses.  Guess I'll pull the oil pan and use up that extra oil pan gasket set I have.  I'm sure I will be contacting you guys again. This forum is awesome! 

[Brad Ipsen CLC #737]

Checking the valve clearance is very important even with hydraulic lifters.  I did not and it is frustrating to do it out of sequence after you have put the engine all together.  It is not mentioned in the shop manual because it is for new engines and new parts.  The hydraulic lifters have enough range to cover all cases then but when you start rebuilding engines now you don't have new factory parts.  It is a long story on how to do it but check online.  There is a good u-tube on doing it on a Rover V-8 (formerly GM engine). 

[49 Caddy]

  I'm not sure I understand, Brad.

[Bob Kielar]

When I had my 55 Cadillac 331 engine rebuilt we had to use .030 shim's under rocker shaft brackets. This was because the heads were milled and the block decked making the push rods too long. Also make sure the rocker brackets are to correct side down we had one wrong and torqued the rocker arm assembly down. This resulted in bending the shaft unusable and not being able to adjust the lifters. 🤦�♂️ Fortunately I had a good spare shaft lesson learned.
Keep Cruzin,
Bob Kielar

[Brad Ipsen CLC #737]

I looked for the u-tube on the Rover V-8, old GM engine that has the same valve train setup as the Cadilac.  Here is a link.

https://www.bing.com/videos/riverview/relatedvideo?&q=Rover+V-8+lifter+clearance&&mid=01AADAB13906B187922C01AADAB13906B187922C&&FORM=VRDGAR

This is still not easy to explain without going back and forth.  If still having trouble find on old machine shop mechanic that worked on rebuilding engines.  It was a routine procedure.

[Jay Friedman]

I looked for the u-tube on the Rover V-8, old GM engine that has the same valve train setup as the Cadilac.  Here is a link.

https://www.bing.com/videos/riverview/relatedvideo?&q=Rover+V-8+lifter+clearance&&mid=01AADAB13906B187922C01AADAB13906B187922C&&FORM=VRDGAR
...........

Brad, I watched the video. When a friend and I rebuilt my '49's engine in 2007, including milling the cylinder heads, we had to do the same thing.  Instead of shims, we found washers of a suitable thickness which worked perfectly. We had to unbolt the head bolts to remove the rocker arm assemblies in order to install the washers under the brackets (pillars).  I think by doing that we avoided any possibility of the oil passages being blocked, as the video's narrator said was a danger with shims. In any case, compression on my motor is perfect.  The engine now has 30,000 miles on it and runs like a Cadillac should.

BTW: the Range Rover V8 engine shown in the video was first used in 1961 on the Oldsmobile F-85 and a similar Buick model . 

[49 Caddy]

  Awesome video on the subject.  Thanks for your help, guys.  Hopefully I won't have to add anything, neither heads or block were milled.

[Roger Zimmermann]

To help a friend who has problems with his 1955 engine, I watched the video. Oh boy! so much unnecesssary explanation and at the end I still not understood well what he tried to explain. My ears don't have the habit to hear English from the UK, this may be one reason. On the other side, the next video was how to adjust the lifters from a Chevy engine. Even if the construction is different, the result is the same.
Anyway, on the Chevy engine, once the push rod is contacting the lifter and the rocker, 1/2 turn at the self locking nut is the way to adjust the lifter. How easy! As most lifters are more or less the same, what would represent 1/2 turn at the nut: about 1mm (0.04") or less? Or, said differently: what should be the distance between the "C" clip and the plunger at the hydraulic lifter?
I have to give an answer to that friend the next few days; he let restore his engine at the end of last year; the repair shop screwed up and he must begin from the start with new pistons, regrind the crankshaft...

[The Tassie Devil(le)]

......Anyway, on the Chevy engine, once the push rod is contacting the lifter and the rocker, 1/2 turn at the self locking nut is the way to adjust the lifter. How easy! As most lifters are more or less the same, what would represent 1/2 turn at the nut: about 1mm (0.04") or less? Or, said differently: what should be the distance between the "C" clip and the plunger at the hydraulic lifter? ...   

I always thought it was 3/4 of a turn for the V8 and 1 1/2 turns for the Inline 6.   That is what comes from reading the Shop Manual.

Bruce.

[Roger Zimmermann]

In the small film I saw for the Chevrolet engine, it was 1/2 to 3/4 of a turn. As I don't have Chevrolet shop manuals, I still don't know which distance would correspond to 1/2 or 3/4 of a turn...

[The Tassie Devil(le)]

I will have to measure it for you.

Bruce.