RV8 - Lifters and Rockers

garrycol · Post by **garrycol** » Sat May 14, 2016 4:43 am

In building my RV8 4.6 the block as well as the heads needed some skimming - I do not know how much. The head gaskets are composite and when I put the inlet manifold on there were no issues hence I don't think too much was taken off the heads or block.

At the time of assembly I just assumed the hydraulic lifters would automatically account for any differences in the deck height etc.

However lately I have been reading on a few forums where people have had issues with push rods, lifters etc and noisy valve gear where there was a fair bit taken off in the skimming process. As i said I am not sure how much was taken off with mine.

Now I am not going to take the engine apart at this point (the engine has not been run yet) but if I do get some weird valve gear noises etc and need to take the rocker covers off to get at the valve gear what options to I have to correct the issue.

I understand you can get spacers to go under the rocker shaft pedestals to raise the rocker gear a bit but I do not know much about this aspect.

Other options?

Oh - if the valve gear is too tight - what are the symptoms?

Thanks

Garry

ChrisJC · Post by **ChrisJC** » Sun May 15, 2016 6:00 pm

Basically you have to measure the preload on the lifters, and if it's out of spec, then you have to shim the rocker pedestals to correct it.

Chris.

garrycol · Post by **garrycol** » Mon May 16, 2016 12:06 am

Hi Chris and thanks for that - I will have to investigate that further as the engine rebuilt manual does not cover any of this - but I guess it was assuming that when doing the rebuild all parts would be within specs.

Cheers

Garry

petervdv · Post by **petervdv** » Mon May 16, 2016 10:21 pm

Above the procedure how to check the preload as it is not mentioned in many WSM

Peter

mgbv8 · Post by **mgbv8** » Mon May 16, 2016 10:36 pm

Dont get into a flap over this Gary

Skim the heads and deck the block to make sure all your mating faces are flat and will seal correctly.
Thats the first important thing done.

When this is done fit the heads and get them torqued down correctly.

Then fit the lifters making sure that they have all been drained of oil and are loose to press down by hand.

At this stage I would only fit one set of push rods and one set of rockers so you can measure the pre load to get an idea of how the rods fit with the new build on this engine.

I was where you are now with my first Rover V8 build many years ago and I bought a set of adjustable push rods so I could experiment.

You could possibly make a test rod of your own to check this??

Perry

garrycol · Post by **garrycol** » Mon May 16, 2016 11:29 pm

Peter - thanks for that very informative document.

Perry - yes if I did this again it would have been done during assembly - the engine is all back together and i am not going to pull the covers back off at this stage - if there is an issue when she is fired up I will worry then.

The guy who leveled the heads said there would not be an issue but he was not aware the block had also been previously decked.

Thanks for the input has been really helpful.

Garry