3LW tappets

[Maudesmaster]

had Cylinder head refurbed by Gardner Marine
Head on and torqued down  

cylinder 1 approx 12 degrees before TDC and pump lever sloppy 

.254 feeler in both valve tops 

Am I good as away from Gardner’s 

will do same with 2 and 3 

 

[Tony Brooks]

What are you asking, because I can't see where you tell us what you are trying to do.

 

Adjust the valve clearances?

Set the injector pump timing? But why you would need to do that for just a head change, I don't know.

Something else?

 

Assuming you mean valve clearances, the way I would do it on any three-cylinder engine is:

 

Turn the engine until one valve is fully down, and use a bot of chalk or crayon to put a witness mark on the front pulley or flywheel. Align it with any engine feature that is convenient.

 

Turn the engine one complete turn until the witness mark realigns.

 

Adjust the clearance on that valve.

 

Rub out mark and repeat for the other valves.

 

Edited April 23 by Tony Brooks

[jonesthenuke]

I suggest following the instructions in the Gardner manual valve clearances.pdf

 

If you need a manual PM me

[Tony Brooks]

20 minutes ago, jonesthenuke said:

I suggest following the instructions in the Gardner manual valve clearances.pdf

 

If you need a manual PM me

 

As there are specific instructions, then I agree, but I am still unclear where the 0.254 something came from, certainly not your manual extract, and it is about a quarter of an inch. Not likely for setting valve clearances.

 

The method I described will meet the Gardner requirement of having the piston at the top of the compression stroke, almost certainly within the TDC ineffective crank angle.

[jonesthenuke]

And these are the torque settings, but note they are in pound-inches not pound-feet

 

 

And the head should be tightened like this. 

LW Head tightening.pdf

[Maudesmaster]

1 hour ago, Tony Brooks said:

What are you asking, because I can't see where you tell us what you are trying to do.

 

Adjust the valve clearances?

Set the injector pump timing? But why you would need to do that for just a head change, I don't know.

Something else?

 

Assuming you mean valve clearances, the way I would do it on any three-cylinder engine is:

 

Turn the engine until one valve is fully down, and use a bot of chalk or crayon to put a witness mark on the front pulley or flywheel. Align it with any engine feature that is convenient.

 

Turn the engine one complete turn until the witness mark realigns.

 

Adjust the clearance on that valve.

 

Rub out mark and repeat for the other valves.

 

 

I have manual head torqued down and push rods for No 1 cylinder in place 

trying to establish which stroke to adjust tappets 

As an old Scottish ship mate used to say “Mar Heeds a boiling “ I now know what he meant  going back to Canterbury to see if the experts there can explain it in dummy narrow boat owner lingo 

thank you all for input 

[Tracy D'arth]

If you get the valve you want to adjust fully open then turn crank one full turn exactly as Tony said, the valve must be full closed then.  Works for any engine with any number of cylinders.

[Tony Brooks]

5 hours ago, Maudesmaster said:

 

I have manual head torqued down and push rods for No 1 cylinder in place 

trying to establish which stroke to adjust tappets 

As an old Scottish ship mate used to say “Mar Heeds a boiling “ I now know what he meant  going back to Canterbury to see if the experts there can explain it in dummy narrow boat owner lingo 

thank you all for input 

 

Basically, you adjust the valve clearances when the cam follower is on the back of the cam. Cams are normally shaped like a section cut down through the centre of an egg. The back of the cam is the end with the larger diameter. In this position, the valve clearance will be ta its maximum. Whatever method of setting the engine to the correct position you use, it will be designed to set the cam follower on the back of the cam.

 

Note, there are cams that are more rounded than egg shaped, and these are normally adjusted with the engine running. As far as I know, it is mainly General Motors companies that do/did this, so certainly not most UK engines.

 

My method works because the heel of the cam is 180 degrees of rotation around from the peak, so set the valve fully down means the cam follower is on the peak. The question then is, "how do you know when the cam shaft has turned through 180 degrees". That is easy because the cam shaft turns at half engine speed so if the crankshaft is turned through 360 degrees (one full turn) the cam shaft will have turned through 180 degrees, so the cam follower will now be on the back of the cam.

 

Although I will always say follow the manufacturer's instructions, the Gardner method seems a bit complicated, but it seems clear enough to me. It is still designed to get the cam follower on the back of the cam.

 

Don't worry about which stroke, just get the follower on the back of the cam. Both valves will be closed around TDC compression

 

As both are at a very similar position and the back of the cams have a number of degrees of rotation where they do not lift the follower, it allows you to use piston pairs on an engine with an even number of cylinders and this is what I think is confusing you. Using piston pairs that is not possible on your engine, you would set the non-adjusting piston pair to be around TDC between exhaust and inlet stroke. That puts the adjusting cylinder at BDC

 

Edited April 23 by Tony Brooks
Cocked up both valves closed position, now edited

[David Mack]

2 hours ago, Tony Brooks said:

As there are specific instructions, then I agree, but I am still unclear where the 0.254 something came from, certainly not your manual extract, and it is about a quarter of an inch. Not likely for setting valve clearances.

0.254mm = 1/100 inch or 10 thou?

[jonesthenuke]

1 hour ago, David Mack said:

0.254mm = 1/100 inch or 10 thou?

I agree but it is still the wrong dimension, should be 5 thou inlet and 11 thou exhaust according to the manual.

[john.k]

Seen Gardner rockers broken by turning the valve spring cap one turn too many onto the valve ..........so thats one thing can go wrong.

[Maudesmaster]

1 hour ago, jonesthenuke said:

I agree but it is still the wrong dimension, should be 5 thou inlet and 11 thou exhaust according to the manual.

 

[jonesthenuke]

Re the 10 or 11 thou exhaust clearance, the smaller value was in the earlier manuals and 11 thou in the later versions. I doubt the difference will be of any import. I set ours to 10 thou as that is what is cast into the rocker cover, the engine is circa 1960, the later version of the manual is from (I think) 73.

[john.k]

Large clearances generally indicate cams ground with quietening ramps .

[Maudesmaster]

Thank you all for input 

I wanted to know when to adjust tappet clearance but in a state as boat in midlands and me in Canterbury waiting for hip replacement this Saturday 

Mind was going haywire 

It is now clear to me tappet has to be set (.254mm or 10 Thou/in as per rocker cover /manual)when push rod fully down ie valve fully closed irrespective of stroke 

will have to wait to get back to boat in about 5 weeks 

thank you all again 

Richard 

[jonesthenuke]

Best wishes for the Hip operation.

 

[Maudesmaster]

2 hours ago, jonesthenuke said:

Best wishes for the Hip operation.

 

Thank you 

[Tony Brooks]

3 hours ago, jonesthenuke said:

Best wishes for the Hip operation.

 

 

Ditto from me.

[Maudesmaster]

Thank you