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Click Click Click sound in motor


DaleC

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Some time back the question was raised about the tapping sound that some motors make. My 10 Hp briggs has that clicking tapping sound. I may have figured it out. It is the same sound that the old Indian and Harley pan head motorcycles make. It is the Valves.?
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Dale that's my thought too. I've had some old "push rod" Harley and British singles with the same sound. Seem normal to me! It's the Kohler twin on the 17GTH-L that sounds odd to my ears. Larry
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Each one of my B/S engines has it's own particular noises most of them are of the tick-tick variety. I feel that this rather normal considering that some of these engines are near 40 years old. I've decided to worry only when the noise is a rod ready to make it's way through the block. I'd like to keep at least 1 engine as a spare but all I really have are piles of worn out parts! LOL And your probably right about the noise being from the valve train, I've checked a couple of my engines and found that they've had excess valve clearance. Now if I had a valve seat grinder this wouldn't be a problem.......
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Hi, I have seen this. I do not have an answer as to why the tappets in L head engines get looser. I suspect that it comes from the end of the stem wearing off. I do not know the cause of the process, unless it has to do with the hardening process on the stems. It can't be the camshaft, because there is no pressure on the heal of the cam. I know it is common in the Kohler KT series engines, I have heard a number of them this way, and it seems like only one tappet. I do have an explanation as to why they get tight. As the valve seat wears down and the valve face wears a groove in it, the clearance is reduced by the same amount. I do know that when the tappets get loose in a Briggs, the compression relief bump in the cam lobe doesn't lift the valve off the seat to drop the compression. The result is that the starter does not have torque enough to turn the engine over on compression. The Brs OHV single engines are very prone to this problem and the cause is the cumulative effect of a series of wear points. Many starters and batteries have been replaced when the problem is loose tappets. On the OHV engines,the tappets NEED to be at minimum clearance too start well. My 2 cents worth and its free, value accordingly. Al Eden
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Hi, In setting here and thinking about the loose tappets in the L head engines. I think I may understand the problem. When we have L heads Bored, we usually have the blocks decked. We have it done in a Bridgeport mill. We just have the surfaced touched, no metal removed at the low point, across from the valves. Many of the decks are about .005 high around the exhaust valve and this would hold the valve .005 more off the tappet. Usually after we have one decked it doesn't swell any more and seems to stay flat if rebuilt a few years later. It seems like a heat curing process in the block. I guess it was bugging me as to what had to be happening, when I started to think about what I had seen that would explain the happening. I encourage any other discussion on this subject. My 2 cents worth, its free value accordingly. Al Eden
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I understand the mulling over of a problem like this in your mind till you figure it out. I would never have thought of the heat curing process. The block carries away more heat than thin exhaust metal, but I have often wondered the effect when the exhaust gases turn the exhaust cherry red. My stack muffler gets red half way up. That is one reason I like to mow after dark. I can see the exhaust. The sun is not as bright either!lol
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