I have built my 235 a few times over the past 15 years and for some reason, lately, I keep spinning bearings while driving down the freeway. I was so pissed hearing the clatter that I decided to stay in it and blow the f**er to the moon. I just rebuilt it a month ago. I installed an oil filter and it seems like it could be the source? Curious what other guys have come across over the years, are they prone to low oil or am I a dipshit.
120k personal miles on a '56 235. No excessive oil consumption, no oil filter, twice a year oil changes, many 1k+ trips, many hours of 70-75 mph cruising. Looks like you ride them hard and put away wet (mistreat the animal).
Ran mine 60-65 regularly 3:55 gears. Will get a 3 speed OD when put back together. these have RPM limits
I'm guessing the filter was a bypass not a full flow ? how was the oil pressure ? excessive main bearing clearance can lead to rod bearing failure.
I had TRIED to blow one up in my '65 C30. This thing belched oil from everywhere, severe blow by. I was doing a 283 conversion and I figured I'd send the 6 out in grand style. Dumped the oil out of it, drove it around the 'hood for a good 20 minutes. It started to make more upper end noise than usual, the oil light glowing. But it refused to blow. Maybe due to it being as loose as a $5 whore inside.
I had one of those years ago,i bought it with a knocking motor,didnt know why it was knocking,It had a bad rod end from lack of oil?.Rebuilt it and all was well for a few days,was driving one day and it started to knock bad,lost oil pressure and boom she blew up.Towed it home and come to discover the distributor was loose on the clamp that holds it down in the hole,it had moved up enough so it would run,but disengaged from the oil pump?.Have a look at yours and see if it is the same. harvey
The only guess I have is the filter plumbing may not include the proper proper flow restriction and allows too much to bypass the bearings. Been a long time since I worked on a Chevy, but Mopar flathead sixes have a fitting with a really small hole to control that, along with a valve the opens only when proper pressure is present.
Me? I would never trust that enough to re-use, no matter what. Even a new set of factory rods (thoroughly inspected) is not a lot of coin. I probably throw away more "good" parts than most here do.
The restrictor in the oil supply to a bypass style filter should be approx 1/16" (.060"). BUT if your oil pressure on the gauge was not reading low then the filter or restrictor isn't the problem.
Well, I checked the oil gauge WITHOUT the filter attached on the engine stand. How did you restrict the oil? Machine a fitting with a .060 hole?
I seem to remember those had an oil distribution / pressure regulator gizmo on the right side of the block (?) Maybe on the left. Anyway, if it uses one like the 216 did it could be defective. I don't remember a restrictor fitting on the filter. That was a Ford thing. I think you need a new block, also. That one is cracked. You may have one or more blocked oil passages. Looking through to peep hole in the pan, that rod looks drier than a popcorn fart, indicating insufficient oil. Did you clean out the passages in the crank the last time you worked on it? You should spend the bucks for a service manual.
I'm not much help with the six, I only ever rebuilt one, the tired 292 in my girlfriend's newly bought '67 C10, in 1973. The only thing I can remember is what seemed like a hundred crack stitching plugs which successfully repaired the previously frozen water jacket, which had been glopped over with something that dissolved in the hot tank. The engine outlasted the relationship by a decade. The good news is, I've loved C10s ever since and I really like your truck, man.
Oohh Baby , Imperial valve covers too ! ,,,,,that’s a nice one there . Look at it this way,,,,it’s a sign you needed to swap engine brands ! That Hemi will more than make the pain go away from the windowed block . Tommy
I've had my 261 over 90 M.P.H. several times, with no issues. What are you running for rod bolts? By resizing the rod bolt hole ARP 460 Ford rod bolts can be used in a 235/261. I have done this in both of my 261s. In the early 261 54 early 55 261 design some clearance is needed for the bolt head.
If the 235 block is windowed, its a bit late to be too concerned about that one. The time to analyze the problem was before the block got windowed. Not that I blame you if it was really "rebuilt" a few months ago, and it had that problem before, I would probably have killed it too. Now, if the motor had this problem before and the crank was not turned, and the rods were not resized before new bearings were shoved in and it spun the bearings again, blowing it up may have been a bit over the top. My wife's cousin had a 63 Chevy pickup and he kept complaining about blowing up small block Chevy motors. I told him I had a motor he couldn't blow up. We put a 318 Mopar in the Chevy truck. He bet me the motor didn't stand a chance, but he killed the truck trying to blow the 318 up. To this day, he is still mad about his Chevy truck dying with that 318 in it. I never did collect any money on that bet, but rubbing that in was worth the effort to install the 318. LOL!
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