Stuck Rocker arms :S

[GreenVan]

Good news everyone!

I got myself a replacement 850cc engine for my 4F4, and after fitting it I tried starting it...without luck. After alot of ignition timing adjustment, I thought of checking if the valves played ball. I found that 4 (yes 4) of the rocker arms were stuck. I guess the engine has been sitting for some time.

How do I get these rockers moving freely again? They can be tapped lightly with a small hammer, and they move when the pushrod is on them, but still too tight for the valve-return spring to budge them back. I reaaaallly do NOT want to dismantle the head. Help is much appreciated

Kenneth, Denmark

 

[kevinandkate]

First of all make sure its the rockers that are sticking and not the valves, if it is the valves you will probably have to remove the head and dismantle it all. If it is the rockers they are heavily coated in oil deposits, usually dark grey, try removing the rocker shaft and soaking the whole shaft in diesel fuel for a couple of days then wire brushing it off. If not then a good penetrating oil and repeated movement of the rockers by hand may free them off. I'm sure the whole shaft can be dismantled and freed off at the same time. Don't use abrasives on the shaft as this will cause wear.

 

[Steve Hennessey]

Just be aware that if the rocker arms and / or valves are sticking then that engine has been standing for a very long time and there may be other problems as well such as stuck piston rings and rusty cylinder bores.
I really do agree that the cylinder head should be removed, even just to inspect the bores.

 

[GreenVan]

The valves and pushrods are in good order, and the cylinders had a small amount of what seemed to be wd40 in them.

The slugde on the rockers appear rather thick and has a rubbery consistency.

I did fire a good amount of WD40 on them last night, and I will try to get them going again today, hopefully with a subsequent clearance adjustment.

Kenneth, Denmark

 

[GreenVan]

My little green 4F4 is running fine now, and it just passed the MOT

 

[jjad]

Good news - well done on getting it fixed