Took the V8 out for a run recently and it sounded like I had left a bag of spanners under the bonnet. Turned around as soon as I could and went home slowly.

It sounds like one of the Rhoads lifters has failed and is not pumping up. No probs I thought, I will identify which one and replace it. Err no, can't do that. Not good practice to put new followers on an old cam or visa versa. So I either take the lifter out and try and fix it, or buy a new cam and new lifters at a cost circa £400!

And I need to have it all done before Stonleigh so I can give it a few test runs beforehand.

I'm only familiar with Redtop hydraulic tappets,

but IIRC they can be disassembled?

Can you buy one new one, strip it & put the new innards

underneath the original follower?

I have re used lifters on Ford v8s before. All i done was got some fine wet n dry with a load on 3 in 1 oil and polished the mating surface in a figure of 8 untill it was mirror like. Worked fine and still is.

 

To clean them i just left in a bath of petrol and scrubed clean with a tooth brush. Amazingly a ton of old oil came out.

Edited March 5, 20179 yr by lotusPaul

My v8 used to start tapping every now and then always cleared on its own accord thou

Edited March 5, 20179 yr by DanE

Lifters usually don't full up if they can't spin freely. Just check they all rotate very, very easily with light finger pressure Tim before condemning to much?

Cheers lads, spanners out and away we go. Fingers crossed for a cheapish fix.

Tim, look for a circular wear pattern (if theres anything visible at your low miles) on the cam end. That should help diagnose a non spinning one.

Tested them all and the three suspect ones I could turn the push rods even with the rockers still on. Makes me think the preload was wrong. Took the lifters out and no sign of wear on any part of them!

All lifters span easily.

Have you shimmed the pedestals at all?

Different cams require different shim plates?

If you do play about with some, remember the oilways pass through them.

I assume you know about these V8 specialists?

http://www.v8engines.com/engine-4.htm

Yes I also know how expensive they are.

I have ordered a shim set and read and re read how to check preload.

Whilst stripped, check the pushrods are all equal length.

Also, I know your far from daft Tim, but are all the pushrods the right way up? The ends are subtly different.

Quick look and they are all in the same way up. The problem didn't arise until I changed the heads. Which is leading me towards the preload issue.

Edited March 7, 20179 yr by Tim Norman

Quick look and they are all in the same way up. The problem didn't arise until I changed the heads. Which is leading me towards the preload issue.

I'd fully agree mate, especially if the old heads had been skimmed and then the rocker shaft pedestals had been shimmed to suit.

 

Fingers crossed its just a reshim mate...

Hoping so, but at the minute I am considering a full cam and lifter change as the cam I have is just one step up from standard. The heads are almost full blown race heads so a change to something like the Typhoon cam would be a straight swap. and get me a lot closer to the magic 300Bhp