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Nick Joubert
Yet to post message
Username: nickjag

Post Number: 1
Registered: 02-2020
Posted on Sunday, 09 August, 2020 - 19:49:   Edit PostDelete PostView Post/Check IP

I am assembling my engine, SRH 1339< after replacing liner seals. when i install the camshaft gear with the lined up, as shown in the manual, with A1 and B2 at TDC, all the bolt holes aligned between the gear and the cam, A1 valves are rocking. when i turn the engine to A1 on compression the cam timing mark is 180 degrees out. any ideas/suggestions?
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 116
Registered: 07-2018
Posted on Monday, 10 August, 2020 - 03:00:   Edit PostDelete PostView Post/Check IP

The engine has to be turned two revolutions until the cam marks line up again.
This is because the cam turns half as fast as the crank.
What you think is compression, is more then likely on the exhaust cycle.

At this point, this is what appears to be your problem.
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Nick Joubert
New User
Username: nickjag

Post Number: 2
Registered: 02-2020
Posted on Monday, 10 August, 2020 - 05:28:   Edit PostDelete PostView Post/Check IP

Hi Jeff
i have turned the crank and watched the pushrods
until they rock on A1 the timing marks line up on the crank and cam gears. another rotation to compression on A1 and the cam timing mark is at the top of the engine i.e. 180 degrees out. the rocking is not very high as the followers are new and still empty. the cam cover is of and you can see the position of the lobes.
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 117
Registered: 07-2018
Posted on Monday, 10 August, 2020 - 17:13:   Edit PostDelete PostView Post/Check IP

The only thing that I can come up with at this point is what you think may be compression, isn't.

And if the lifters are empty, then I'm going to assume that they are new.
They need to be filled with oil, first.

The engine is put on number one (A1) at TDC and the cam timing marks should be placed facing each other and at that point both intake and exhaust valves should be closed.
One full revolution of the crank will the bring the timing mark on the cam at the top of the cams timing gear.
That will put A1 at TDC and on the exhaust stroke.

Another revolution of the crank will make the timing marks meat up again and A1 will be on the compression stroke, both intake and exhaust valves will be closed.

A 4 cycle engine will only be on compression after two revolutions of the engine.
One rotation will bring A1 to TDC, but that is the exhaust stroke, I think you're confusing that with the compression stroke.
That's why it's appearing to you that it's the compression (power stroke if you like) and you're thinking that it's 180 degrees out.
The timing mark is supposed to be 180 degrees out after one revolution of the crank, because it's on the exhaust stroke.

It's the same when timing the distributor, it's a common mistake to set for spark on A1 at TDC when it's actually on the top of the exhaust stroke.

Here is a video on how to fill the lifters.
The guy is gently releasing the check valve on the top of the lifter and pumping it while it's immersed in oil.

Go to the 20 minute mark and let it go.
It's a Silver Cloud 3 engine, but I think it's pretty much the same.

https://www.youtube.com/watch?v=HPJ98Er75kM
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Nick Joubert
New User
Username: nickjag

Post Number: 3
Registered: 02-2020
Posted on Monday, 10 August, 2020 - 21:02:   Edit PostDelete PostView Post/Check IP

I have heard conflicting comments on starting the engine with new followers and reconditioned, is to crank until you have oil pressure. then start the car and immediately bring the revs to between 2000 rpm and 3000 rpm, varying the revs for 1/2 hour to allow the followers to bed with the cam. I have a load of assembly lube on all moving surfaces to prevent initial wear. what is your opinion?
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 118
Registered: 07-2018
Posted on Tuesday, 11 August, 2020 - 03:35:   Edit PostDelete PostView Post/Check IP

The lifters need to be filled with oil as in the video.
With out oil in them, it takes a while for them to be pumped up in a running engine, it just doesn't happen right away.
In the mean time, it makes an incredible amount if racket.

With todays machining practices, modern equipment and lubrication products, all that has become redundant.
Yes, it is important to use assembly lube because it does take a bit for the oil to get everywhere, so turning the engine over with the starter until you see oil pressure on the gauge isn't going to hurt anything.
(leave the plugs out while doing this)

On first start, look for any oil and coolant leaks, and drive it right away if there are none.
Keep an eye on the coolant level on first drive as air works its way out of the system.

Don't drive it hard, revving it to 2 to 3000 rpm when the engine is cold is not good for it, or any engine for that matter.

With todays modern oils, especially synthetic, cam break in doesn't really matter any more.
Don't leave it to warm up in the drive way, all that does is create condensation in the valve cover and create a milky mess.
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Nick Joubert
New User
Username: nickjag

Post Number: 4
Registered: 02-2020
Posted on Tuesday, 11 August, 2020 - 19:38:   Edit PostDelete PostView Post/Check IP

Ok cam followers have been filled and bled. Engine has been turned over, with the cam cover off, and watching the cam. timing is fine. I just need to make sure everything is perfect when i start up.
This is the most expensive and over engineered engine i have rebuilt. thanks Jeff for your input.
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Jeff Martin
Experienced User
Username: jeff_r_1

Post Number: 119
Registered: 07-2018
Posted on Tuesday, 11 August, 2020 - 21:49:   Edit PostDelete PostView Post/Check IP

On any any engine, and even more so on a RR engine to carefully check your work as one goes along.

At least the valve timing is pretty straight forward on it, just line up the marks when A1 is at TDC.
But one can never be too carful when it comes to that.
The thought of bending a valve can get quite expensive.

You probably don't need reminding, but remember to fill the oil filter with oil when it comes to getting oil to the mains.

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