rockerarms 1955 Rocker arms

[Kanne]

Hi

I am doing a total rebuild on my 1955 331 cui engine.
During that work I saw, that there were some shims placed under the rocker arm assembly.
They do not look like something original, and I wondered if they have to be installed again, when mounting the rocker arm assembly to the cylinder heads.
What are they good for?
I can only see, that they are making the distance between the valve lifter and the rocker arm longer?
Could that longer distance cause problems with the valve lifters (they are all new by the way).
If I remove these shims, could that result in a too short distance between the valve lifter and the rocker arm, and how do I check, that I have the correct distance?

I hope my English writing is understandable, and that someone can tell me what to do.
Looking forward to some assistance.

Best regards
Per Kanne
Denmark

 

 

Edited June 2, 2019 by Kanne

[BodybyFisher]

Hi Kanne, @Kanne

Your English is perfect.  My parents actually owned a 55 Fleetwood with a 331 ci engine when I was a child we went across the country in it in 1964,

I think that this thread may shed some light on your shim issue. Let us know how we can help,  See this

http://forums.cadillaclasalleclub.org/index.php?topic=149020.0

 

[Kanne]

20 hours ago, BodybyFisher said:

Hi Kanne, @Kanne

Your English is perfect.  My parents actually owned a 55 Fleetwood with a 331 ci engine when I was a child we went across the country in it in 1964,

I think that this thread may shed some light on your shim issue. Let us know how we can help,  See this

http://forums.cadillaclasalleclub.org/index.php?topic=149020.0

 

Hi again.

Thank´s a lot for the link. I have read it, at it make sense for me.

I will try to install the rocker arms without the shims, and see how it looks regarding the length of the pushrods, clearance and preload on the valve lifters.

Thank´s again.

Regards, Per

[BodybyFisher]

@Kanne. Sounds like a good plan.  Be sure to check the clearance when hot also as the pushrod will change in length

Do you have a 55 service manual?

[BodybyFisher]

Per, This problem would be eliminated with adjustable rocker arms.  See this

https://www.jalopyjournal.com/forum/threads/stude-adjustable-rocker-arms-as-used-for-early-cadillac-v8-engines-331-etc.1093340/

 

 

[Kanne]

15 minutes ago, BodybyFisher said:

@Kanne. Sounds like a good plan.  Be sure to check the clearance when hot also as the pushrod will change in length

Do you have a 55 service manual?

Yes I do, but I haven´t seen anything related to that issue.

[BodybyFisher]

19 minutes ago, Kanne said:

Yes I do, but I haven´t seen anything related to that issue.

It seems that it is related to non adjustable rocker arms so shims are used to get proper clearance.  This is no doubt the reason for the Studebaker adjustable rocker arms.  

[BodybyFisher]

@Kanne. Hi Per, what is the status, hows it going?  Mike

[Kanne]

Hi Mike

At first (a couple of weeks ago) before I actually started this thread, we installed new valve lifters and mounted the rocker arms with the shims. (because they were there when we disassembled the motor)

At first start-up of the engine it made a terrible noise, and we stopped the motor. One push rod had popped out of the lifter and it was bend.

We checked the liftes, and found out, that (although they were new) the had were much "slack" at the top piston, where the push rod is placed. We then purchased a new set of lifters from a different manufacturer (Elgin), and they looked much better, (a different construction).

We installed the new lifters, replaced the bended push rod, and installed the rocker arms without the shims.

Now the motor is running as good as ever. Also when it is warm. So I think we should have left out the shims in the first place.

It seem like the engine rebuild is going to be a success.

Thanks for all the help.

Best regards Per