Thread: How loose should a new RV8 timing chain be?

Phillip, The only really tight ones I have experienced have been dual row roller type. The morse ones aren't anywhere near as tight when assembled, Can't remember exactly how much but they aren't tight, thats for certain.

Yes, I'd fit new lifters, they will remain 'soft' after being bled down without oil supplied under pressure during operation.

JC

Originally Posted by justinc

Phillip, The only really tight ones I have experienced have been dual row roller type. The morse ones aren't anywhere near as tight when assembled, Can't remember exactly how much but they aren't tight, thats for certain.

Yes, I'd fit new lifters, they will remain 'soft' after being bled down without oil supplied under pressure during operation.

JC

And I found that the dual row roller type scrape on the Dizzy input on the timing cover and also scrape on the oil pump plate., Some angle grinding on the timing case was needed to remove a casting bump

Yes, I'd fit new lifters, they will remain 'soft' after being bled down without oil supplied under pressure during operation.

I was referring to new lifters that I bought with the cam. Just that I pressed one down hard and it hads remained soft while most resist all my weight on them without moving.They must have been pre primed. each was in its own little oily bag.
AFAIK (25 years ago), I primed the lifters by pressing them down in oil, but with these it was not possible even with my 115Kg on them.
Regards Philip A

Timing chain spec: Using a tension wrench and applying 15 lb/ft to the cam bolt in either direction should result in less than 4.7mm / 3/16" movement in the cam sprocket, with the crank locked. (From the P76 factory workshop manual, for Morse chain)

The best way to prime lifters is to assemble the engine, minus the inlet manifold and rocker covers, remove the dissy and spin up the oil pump with a 1/2 inch power drill and adaptor, assuming you have the old style oil pump on the front cover. I usually run the drill for 2-3 minutes on any V8 engine I reassemble.

less than 4.7mm / 3/16" movement in the cam sprocket, with the crank locked. (From the P76 factory workshop manual, for Morse chain)

Yes the movement would be less than that , but no wonder car makers went to crank sensed ignition. The timing would wander around at will with that slop.
So I pulled off the oil pump top today to prime it with the old Vaseline. Of course the gasket broke into a hundred bits. Land Rover must be the only ones in the world to use 5/16 12 point bolts. Took a bit of searching to find a couple of those. Then about an hour patient careful scraping to get the surfaces clean.
Regards Philip A

Originally Posted by PhilipA

Yes the movement would be less than that , but no wonder car makers went to crank sensed ignition. The timing would wander around at will with that slop.
So I pulled off the oil pump top today to prime it with the old Vaseline. Of course the gasket broke into a hundred bits. Land Rover must be the only ones in the world to use 5/16 12 point bolts. Took a bit of searching to find a couple of those. Then about an hour patient careful scraping to get the surfaces clean.
Regards Philip A

I don't use vaseline any more, the drill trick works every time. Oil pump dry (assembly oil only), my drill runs at 1600rpm which is equal to 3200 crank rpm. Vaseline doesn't melt until the oil gets hot enough, it can take quite some time for it to clear the lifters. Priming by injecting oil into the pressure switch port works as well, works on the later crank-driven pump too. All you need is an adaptor and a hand pump oil fill bottle.

Thanks for that . I had to dismantle the oil pump anyway as I had about 1/2 inch of muck all over the timing case so had to use a Gerni and degreaser to get it off. I didn't trust myself not to get some water or degreaser into the pump, which I did.

But that oil pressure switch idea sound great, and I am going to fill the oil cooler lines and filter also.

Hopefully after this, I will not have to dismantle it for many years.
Regards Philip A

Don't forget to "run in " the new cam and lifters, keep the revs up to around 1200/1500 rpm for 20 mins or so when it first starts, Regards Frank.