How loose should a new RV8 timing chain be?

[PhilipA]

I have just fitted my new cam ( standard 3.9 ) to my 92 RRC.
I guess it cannot be otherwise but the new timing chain has a lot of slack.
The chain is a Borg Warner Morse and who knows sprockets.

The chain has no "lift" on the sprockets so that is good, but there is 8MM deflection on the loose side with the other side held tight. I guess you need some slack or you would not get the cam back in.

Any feedback on whether this is good bad or indifferent?

BTW the old chain was in good nick and the cam also. Some of the followers had a little wear and the lobes were 0.5MM smaller from heel to toe than the new parkerised cam. At 196KK That is not bad methinks. it could have gone years.

BTW , in an attempt to pump up the lifters , I placed one in the vice and pressed it down about 50 thou or so. This lifter is now soft while the others are really firm. Do you think I have damaged it? I will probably buy another one on Monday just to be sure as it is a hell of a job to tear the inlet etc off just for one lifter.
Regards Philip A

[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

[It'sNotWorthComplaining!]

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

[PhilipA]

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

[bee utey]

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.

[PhilipA]

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

[bee utey]

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.

[PhilipA]

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

[Tank]

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.

[PhilipA]

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.

Yep, and its all smeared with assembly lube also, and the cam is "parkerised", and I will get the oil pressure up before starting.
Regards philip A

[400HPONGAS]

How close to the cam card specs did the cam "degree" into ?

[PhilipA]

Seeing no specs came with the cam, it would be hard to degree it. It appears to be a standard 3.9 cam, as that is what I bought.

I have just fitted a standard timing chain and sprockets so I cannot degree it anyway unless I go out and find offset keys and it is unlikely that I would find long ones like in an RV8 easily.

I know you are taking the **** , but who would bother on a 200Kk engine?
I can degree it just by moving it backwards and forwards through the timing chain slop.

Regards Philip A

[400HPONGAS]

"I know your just taking the ****" why is that ? Im not !
Seriously , the way that engine will perform is greatly affected by where that cam is .
Degreeing is only checking where the cam events will occur . You only need the adjustable gears if you want to alter that . All you need is the degrees at .050 lift to determine whether this cam is going to work in your engine. A dial indicator, piston stop and a degree wheel . If its alleady done 200000K then why are you fitting recon heads,cam and lifters , who would bother ? perhaps you would !