Tappett Brothers help needed

PC/SR

Well-known member
My 31 engine has a click click--clack clack sound that sounds just like a mal-adjusted tappett. I have adjusted the tappetts 3 times and does not go away even just after adjustment. It starts a second or two after cold start up, and gradually diminishes as it warms up, but never goes completely away. Loudest on right side over valve cover, but can be heard on the stethascope about anywhere on the block. Does not change with engine load or accelleration or decelleration. Not a knocking sound. Present with fan belt off; one piece front pulley is tight, crank nut really tightened down, nut does press against the pulley, not the crank end. Have .010 oversized distributor drive gear but still a little play there. New distributor drive gear hold down spring. The cam drive gear does not move as viewed with inspection cover removed and a new (repo) plunger spring there. Removal of that cover also establishes oil flow over the cam drive gear. Compression and performance is fine. Have checked for piston slap by disconnecting spark plugs, no change. No play in the oil pump. Cam reground to a touring grind by a very reputable grinder. Dont recall the exact cam journal diameter, but was measured and discussed with grinder and was within tolerances, 1.557 I think?
Could not get hold of the Tappett Bros so calling on the Barners for ideas because I'm out of 'em. Otherwise, as one club member suggested, just drive it 'till it breaks. Thanks to all.
 
Blocks and tappets will both wear and cause a noise as you describe. The solution is oversize tappets and ream the block to fit. I have done this without pulling the engine, but is a lot of work! I used Chrysler '6' tappets.
 
Jim, Where did you aquire the Chrysler '6' tappets? I have been looking on e-bay for them for awhile, but have not seen anything other than the guy wanting to sell just the single lock adjustable bolts for $50 per set. Thanks Rod
 
My 31 engine has a click click--clack clack sound that sounds just like a mal-adjusted tappett. I have adjusted the tappetts 3 times and does not go away even just after adjustment. It starts a second or two after cold start up, and gradually diminishes as it warms up, but never goes completely away. Loudest on right side over valve cover, but can be heard on the stethascope about anywhere on the block. Does not change with engine load or accelleration or decelleration. Not a knocking sound. Present with fan belt off; one piece front pulley is tight, crank nut really tightened down, nut does press against the pulley, not the crank end. Have .010 oversized distributor drive gear but still a little play there. New distributor drive gear hold down spring. The cam drive gear does not move as viewed with inspection cover removed and a new (repo) plunger spring there. Removal of that cover also establishes oil flow over the cam drive gear. Compression and performance is fine. Have checked for piston slap by disconnecting spark plugs, no change. No play in the oil pump. Cam reground to a touring grind by a very reputable grinder. Dont recall the exact cam journal diameter, but was measured and discussed with grinder and was within tolerances, 1.557 I think?
Could not get hold of the Tappett Bros so calling on the Barners for ideas because I'm out of 'em. Otherwise, as one club member suggested, just drive it 'till it breaks. Thanks to all.

Mr, PC, What did you set the clearance at. Herm.
 
My 31 engine has a click click--clack clack sound that sounds just like a mal-adjusted tappett. I have adjusted the tappetts 3 times and does not go away even just after adjustment. It starts a second or two after cold start up, and gradually diminishes as it warms up, but never goes completely away. Loudest on right side over valve cover, but can be heard on the stethascope about anywhere on the block. Does not change with engine load or accelleration or decelleration. Not a knocking sound. Present with fan belt off; one piece front pulley is tight, crank nut really tightened down, nut does press against the pulley, not the crank end. Have .010 oversized distributor drive gear but still a little play there. New distributor drive gear hold down spring. The cam drive gear does not move as viewed with inspection cover removed and a new (repo) plunger spring there. Removal of that cover also establishes oil flow over the cam drive gear. Compression and performance is fine. Have checked for piston slap by disconnecting spark plugs, no change. No play in the oil pump. Cam reground to a touring grind by a very reputable grinder. Dont recall the exact cam journal diameter, but was measured and discussed with grinder and was within tolerances, 1.557 I think?
Could not get hold of the Tappett Bros so calling on the Barners for ideas because I'm out of 'em. Otherwise, as one club member suggested, just drive it 'till it breaks. Thanks to all.

What was the clearance on the center cam main at the time of rebuild? Herm.
 
Herm: .003-.004.
Farrell: Did not install valve seats this overhaul, do not recall if they had been done by someone else previously. Thanks for the idea.
 
"Does not change with engine load or accelleration or deceleration."

I don't understand how this could be. It would seem that this fact alone would narrow the possibilities considerably.
 
Mine has a knock and it turned out to be the oil pump bearings. Not to worried as they are bathed in oil but will have be dealt with eventually.

Mike
 
My 31 engine has a click click--clack clack sound that sounds just like a mal-adjusted tappett. I have adjusted the tappetts 3 times and does not go away even just after adjustment. It starts a second or two after cold start up, and gradually diminishes as it warms up, but never goes completely away. Loudest on right side over valve cover, but can be heard on the stethascope about anywhere on the block. Does not change with engine load or accelleration or decelleration. Not a knocking sound. Present with fan belt off; one piece front pulley is tight, crank nut really tightened down, nut does press against the pulley, not the crank end. Have .010 oversized distributor drive gear but still a little play there. New distributor drive gear hold down spring. The cam drive gear does not move as viewed with inspection cover removed and a new (repo) plunger spring there. Removal of that cover also establishes oil flow over the cam drive gear. Compression and performance is fine. Have checked for piston slap by disconnecting spark plugs, no change. No play in the oil pump. Cam reground to a touring grind by a very reputable grinder. Dont recall the exact cam journal diameter, but was measured and discussed with grinder and was within tolerances, 1.557 I think?
Could not get hold of the Tappett Bros so calling on the Barners for ideas because I'm out of 'em. Otherwise, as one club member suggested, just drive it 'till it breaks. Thanks to all.
Sometimes noises can be localized better by a stethoscope with the probe removed and just listen with the open hose and don't touch the block, just hold it close.
 
Have not definitely found the problem but have concluded by process of elimination that it is most likely the camshaft clearance is too much. Good excuse to tear it down this winter and do some things I have been thinking about for awhile anyway.
 
Have not definitely found the problem but have concluded by process of elimination that it is most likely the camshaft clearance is too much. Good excuse to tear it down this winter and do some things I have been thinking about for awhile anyway.

Thinking on your problem tick. Question...do you have an aluminum cam gear in this engine?
 
"Herm: .003-.004."

Is this what you adjusted your valve clearance to?

If so this is not enough clearance.
 
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