I have changed cams but not cam bearings on various engines over the years
with no problems. My present 235 has had 3 cams in it on the same cam
bearings. As long as the clearance is within spec why change the bearings?
If you don't have a bore gage, a visual inspection is probably sufficient.
If you see any copper, the bearing are shot. Best to borrow a bore gage,
though.
On the subject of removing the grill to gain access to the cam, in a word,
don't. Its a lot easier to pull the whole nose off the truck and you don't
have to remove the hood. There are many fewer rusty bolt to deal with that
way. Plus, getting all those grill bolt holes to line up is a real
pain....literally.
-Tom Allen
51 3800
At 10:09 PM 8/23/99 -0400, Hudson29@aol.com wrote:
> Well, fellow oletruckers, having a few weeks to mull this old 235
>situation in my mind has done wonders. Last night, Jack Daniels and I had
had
>a good talk and the problem sorted itself into several distinct areas.
> To refresh this sorry story in your minds, I purchased a used '59 235
>that one of our oletruck listees had surplused in the course of his V-8
>upgrade project. The motor was running sweetly as recently as last Dec., and
>had even returned 22 mpg in a '50 AD 3100. Upon inspection, the motor had
>certain suspicious characteristics indicating it had had the mechanical
>attentions of a first class moron (not our fellow listee but somebody
further
>back in the food chain), and disassembly revealed a bent pushrod, broken
>bolts, stripped screws, butchered engine front plate, worn out set of main
>bearings, worn cam, marginal rod bearings, rod nuts of mixed parentage and a
>generally poor assembly quality.
> Well, by no particular logic, Jack Daniels and I have decided to stay
>with this 235 -- for now. It ran well, and probably will again once certain
>lower end problems are sorted out. I know certain Doubting Thomases
wiseacres
>on this list (and in my head) have warned that the upper end is uncertain
>too, but I guess lightening can't strike twice -- can it? I will repair the
>trouble I have found, put the motor back together, and drive the darn truck.
>I can look for that perfect 261 to mate to the perfect T-5 trannie (or other
>powerplant) after the beast will actually move on it's own.
> OK, that was decided somehow, so now I am going to pull the crank and
>measure it. As was suggested on this list, mebbe new mains can be fitted and
>that will be the end of it. If the crank needs machine work then it will be
>new mains and rods.
> What to do about the cam? The fuel pump lobe is deeply gouged, and if
the
>cam is replaced, I understand that the bearings must also be changed out. Is
>this something I can do "under the shade tree" out back? What tools are
>required? Can a cam place rework just the lobe and leave the bearing
surfaces
>as they are so that the old bearings can be reused? Mebbe an electric fuel
>pump might just settle the issue for the time being.
> Perhaps it would be wiser to just replace the cam and move on. If so,
>what cam would be best? There are quite a variety of grinds available, and a
>little extra poop would not go amiss. Patrick's offer one for mild street
>use, how about any others?
>
>Paul O'Neil, Hudson29@aol.com
>1951 Chevrolet 3600 Pickup Project, See it at:
>The Poor Man's Advanced Design Tech Tips Page
>http://home.earthlink.net/~conntest47/
>Fullerton, California USA
>AEROMARK - Need Rubber Stamps or Signs? See:
>http://hometown.aol.com/hudson29/myhomepage/index.html
>oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
>
Tom Allen
Seattle, WA
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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