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| | | | Joined: May 2006 Posts: 423 'Bolter | | 'Bolter Joined: May 2006 Posts: 423 | I'm still getting used to my new 235. It is running well enough now, but I am having some concerns about the oil through the rocker arm shaft. I'm a little green to these problems.
A few of the rocker arms have had no oil bubbling out of the little hole at the top. Excess oil ran freely from that junction point in the middle. The rocker farthest back was one of the dry ones, and that means that pushrod was completely dry and there was no oil pooling around the disc on the top of the valve either. I don't like this, so I took the whole rocker assembly off last week, cleaned up the rockers, checked for free oil passages in the rockers and cleaned the inside of the shaft halves. I saw nothing obviously plugged up although it seems the rocker shaft is more worn than I would have expected.
I put it all back together again, and it worked just the same. About three rockers do not ooze oil out the top.
So last night I took it all out again and switched the two halves of the rocker shaft front to back. I was hoping the oil would for whatever reason run better to the farthest rocker. The two halves of the shaft look the same. It all works better now, but I still wonder if all is as it should be?
I also noticed last night that a number of the rockers have worn spots where they meet the valve ends - little round indentations. That must make it hard to get good settings from a feeler gauge, eh? Has my newer 235 been driven longer and harder than I have been led to believe?
Karl
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
You are correct about poor valve-lash settings due to the indentations you describe (" . . number of the rockers have worn spots where they meet the valve ends - little round indentations. . . ). One old "solution" was to trim the feeler gauges so that they were small enough strips to fit in the indentations (ugh).
I have carefully ground/polished the rocker surface where they meet the valve stem.
Pre '68 Dave might have better advice.
| | | | | Joined: May 2006 Posts: 423 'Bolter | | 'Bolter Joined: May 2006 Posts: 423 | In case it was unclear, there is plenty of oil to the rocker assembly as a whole. Oil drips all over the place when it is running. At the moment it even rises out of the holes in the all the rockers. Maybe I improved a bad situation to a slightly better situation.
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe | | | | | Joined: May 2006 Posts: 423 'Bolter | | 'Bolter Joined: May 2006 Posts: 423 | Can anyone say if the two halves of the rocker arm shaft are the same?
It may not be the easy way, but it is the Cowboy Way - Ranger Doug Beware of the stories you read or tell; subtly, at night, beneath the waters of consciousness, they are altering your world. - Ben Okri 1953 Chevy 3100 1960 Volvo PV 544 1941 Chevrolet Special Deluxe | | | | | Joined: Jun 2012 Posts: 1,747 'Bolter | | 'Bolter Joined: Jun 2012 Posts: 1,747 | You can pinch the drain side of the oil supply line to increase flow to the rockers. You can take a stone for sharpening knifes and smooth the rocker end that is worn at the contact point with the valve stem. If you have the rocker arms clean and the weep holes open you should see oil at the weep holes. If the rocker arm shaft is worn badly you might need to rebuild the assembly. There are vendors that do this kind of work. What kind of oil pressure do you have? If the oil pump can not keep up with pressure at the bearings you won't have a lot of flow at the rockers.
Steve H
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Can anyone say if the two halves of the rocker arm shaft are the same? Yes, the two halves are basically a "mirror image". Are you sure your shafts are clear all the way to the end (measure with a thick wire, etc)? | | | | | Joined: Mar 2010 Posts: 10,279 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,279 | If there is excessive wear between the arms and the shafts, the oil will leak out between the sides of the arms rather than making it up through the holes in the top of the arms. Realize that you are observing oil flow at idle. The oil pump will increase flow as RPMs increase. With this increased RPMs, you will likely have oil flow through the holes at the top of the arms. The question you need to ask yourself is, do you want to rebuild the engine to as new condition, or drive it for a while and rebuild at a future date? You will need to spend some money on the rocker arms and shafts eventually, and it is likely that there are other well-worn parts lurking inside. If it runs fine, I would drive it and get the rest of the good miles left in it.
Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
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