ATC 70 engine question

[branstetter412]

My newest little ATC 70 has a very slow oil leak from one of the cap nuts at the front of the engine (right behind the front fender). It is a very slow leak and appears to be coming from where the cap section of the cap nut meets the nut section of the cap nut? Can a cap nut break? Or is this an optical illusion and the oil is actuallly coming from somewhere else? It appears as though a previous owner had taken this section off to replace the rings, but it really looks like the oil is coming from the actual nut? Am I nuts? Any help or insight is appreciated.

Ron Branstetter

[shortline10]

Theirs a rubber O ring on that tappet cover that dries up and goes bad . Remove it and check it for cracks and replace the seal . Very simple job .


My newest little ATC 70 has a very slow oil leak from one of the cap nuts at the front of the engine (right behind the front fender). It is a very slow leak and appears to be coming from where the cap section of the cap nut meets the nut section of the cap nut? Can a cap nut break? Or is this an optical illusion and the oil is actuallly coming from somewhere else? It appears as though a previous owner had taken this section off to replace the rings, but it really looks like the oil is coming from the actual nut? Am I nuts? Any help or insight is appreciated.

Ron Branstetter

[ctbale]

are you talkin about one of the head nuts? there are 4 of them, small 10mm wrench size nuts? the lower right one (as viewed fron the rear) torques on a stud that carries oil from the pump to the head, there should be a copper washer under that one, could have been torqued with a thin or no washer, and the stud might have popped off the top of the acorn nut?

[branstetter412]

Yes, you are talking about the correct nut (10mm) lower right side. It did have a washer, but I believe (like you said) that the stud was a hair too long and separated the acorn nut. For now I swapped the acorn nut off the air filter and put an extra washer, tightened it down and for now no more slow oil leak (it was maybe one drip a day when I ran it). I know this is not the "right" way to do it? But don't know how to get that stud any lower. Thanks for your help.

Ron Branstetter

[ctbale]

yea that will work, basicly that stud lives inside the head oil supply galley, the nut hold the cyl/head down and caps the galley off, as long as ya aint leakin too much, its ok. stud might have been streached out a little bit over the years