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MG MGB Technical - lifters tappets

I have a 1979 mgb with emissions off the problem is that one of my rocker arms cant be adjusted because it is to short. That is were i thought it might be worn cam lobe but when you get the pin down far enough without nut their is a clacking noise like the lifter is double pumping. Also if i let the pin loosen up where it is not touching the car gets hard to start i have good oil pressure, did a compression test and seem to be good and could this be a collapse lifter"
adam

Take the lifter out and look!
Art Pearse

The B series engine used solid lifters which cannot "collapse". This is a problem associated with hydraulic lifters. It could be a broken lifter but I have never come across this. I would check the pushrod and then the cam. RAY
RAY

I hope you're adjusting the tappets with the correct clearance. Maybe when you adjust the one down too far, the valve is hitting the piston. Sounds far fetched, but your description sounds like the tapping gets worse the tighter you adjust it. The cars do have solid lifters, requiring a clearance when valves are closed.
Tom

More likely the valve is touching the block. the valves overlap the bore a bit. If this is the case the cam or pushrod is being destroyed.
Art Pearse

According to the Brit-Tek catalog, the industry was overrun with inferior soft lifters for a while. This is especially true for the 18V engine. They recomend lifters sold by AE. They have the Rockwell hardness needed to stand up for the life of the engine. The Rockwell hardness scale is the standard used to measure the hardness of steel industry wide. Also, it depends on what cam you're running. -Steve
S.L. LaPaugh

This thread was discussed between 11/07/2009 and 12/07/2009

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