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#44824 04/10/2004 12:53 AM | Joined: Mar 2004 Posts: 3 Junior Member | | Junior Member Joined: Mar 2004 Posts: 3 | Hi all! I am trying to swap out an older 235 in my '50 burb and replace it with a "newer" ('61) one, the block is a 261, and the head is a 235. I am having trouble with the oiling system. I know that was a big difference in those bigger engines, with the full flow oil system, and specifically the two lines from the pump to the filter and from the filter back to the block. My lines were cut off, and I am trying to find info, especially pictures,sketches of the oil routing system for the 261...any help? | | |
#44825 04/12/2004 3:41 AM | Joined: May 2003 Posts: 8 Member | | Member Joined: May 2003 Posts: 8 | 261 oil. Look for your answer under Tech Tips Great pics. | | |
#44826 04/12/2004 5:10 PM | Joined: Dec 2001 Posts: 1,745 Member | | Member Joined: Dec 2001 Posts: 1,745 | Did you drill the needed steam holes in the 235 head you need for a 261 installation?
Make sure you get the oiling right as a mistake here will leave the engine totally dry.
Basically there are two large diameter oil lines that go to a large filter housing. Do you have the filter?
54 3100 with 235
62 flatbed dump C60 with 261
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#44827 04/13/2004 12:08 AM | Joined: Mar 2004 Posts: 3 Junior Member | | Junior Member Joined: Mar 2004 Posts: 3 | Yeah, actually the holes already appear to be drilled, and while I know that the two large lines run through, I am trying to figure out if the holes drilled and tapped into the lines are right because they seem to be smaller than the lines I have seen in other photos. | | |
#44828 04/13/2004 12:18 AM | Joined: Oct 2001 Posts: 3,458 Extreme Gabster | | Extreme Gabster Joined: Oct 2001 Posts: 3,458 | A full flow 261 should have 1/2" NPT (national pipe) threads into the block. The hole toward the front of the engine is the out to filter and the other hole is the return. There should also be a tee block on the return to mount the sending unit.
I used aftermarket jiffy hose lines for mine, the kind for mounting remote spinon race car filters. They work fine. I had to mount my filter on the front of the intake because it hit the steering box when mounted on the back. I think I still have my old lines if you want them for a pattern.
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