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| | | | Joined: Mar 2009 Posts: 19 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 19 | I purchased a 261 last weekend, and have been doing my homework on it. Always fun to figure things out,the head and block tell me that it's a 58 to 63 series. Head;3836850 Block;3769925 the date code on the head is G 11 1, July 11 1961. Here is the rub, the date code on the block is E 6 5, I'm confused. Also there is a plug in the draft tube hole, and a small plastic fitting in the top rear of the valve cover. So what do you all think? Is this a good score? Do I need to find a draft tube? And what harmonic balancer do I need to find? Thanks!!! | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
You are right about the block casting code and date code being odd.
What diameter are the oil lines to the oil filter? Is there an oil filter. Can you post a photo of it?
Can you post a photo of the water pump side of the engine - you might have a 54/55 style water pump. This will make it easier to install the 261 in your 1949 truck.
The draft tube and valve cover indicate it has/had a PCV system.
Does it have a harmonic balancer?
| | | | | Joined: Aug 2005 Posts: 94 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 94 | What is stamped on the pad next to the distributor? My 261 came from a 55 school bus, but the block is a 3769925, dated D3 3 and the head is 3836850, dated E221, and the distributor pad is blank; probably indicating a factory replacement.
Joe D. | | | | | Joined: Mar 2009 Posts: 19 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 19 | The VIN is another mystery, I think its a CA stamp. KA79252CAL There is no oil filter, just a large 1/2 inch copper loop off a couple of flare fittings. Joe D does your block have a line by the push rods, mine does even though the casting looks like it should feed without it. No water pump or harmonic balancer, the kid who sold it had it all machined, then lost interest. I will try to post pics when I learn how to do it and get started on the engine swap/build. Thanks for all your input as I'm sure I will have more questions. Oh, will my 235 flywheel fit? If you guys have photos of 261 parts that are specific that would help when I go to the swap meets. | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I don't understand what the sopper loop is about. | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Sounds like it's a full flow block that the filter was removed from. On the full flow blocks, a jumper line has to be installed from the rear fitting to the front fitting, otherwise, no oil will get to the engine.
Bill Burmeister
| | | | | Joined: Mar 2009 Posts: 19 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 19 | Full flow engine with no oil filter, as of yet! I will install one as I assemble the motor
Last edited by DiGeM; 05/28/2010 3:12 AM.
| | | | | Joined: Jan 2000 Posts: 2,074 'Bolter | | 'Bolter Joined: Jan 2000 Posts: 2,074 | DiGeM, You really will want to study the oiling system of your 261 as these were set to be run with or without full filtered oiling. Center of the block driver's side 1/2' oil line that has a hole/plug underneith, if the plug is pushed in you must run a filter, if it's out the filter is not needed. And if it's out, you'll want to push the thing in just over half an inch and I'd have the machine shop do that job as it's not easy to move that plug. It also may be easier to drill it out. When you get the plug 'IN' you MUST run a filter. | | | | | Joined: Mar 2009 Posts: 19 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2009 Posts: 19 | What would be the best book/manual for this 261 engine? Something else to put on my swap meet list. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
Since you have a full-flow oil filtration system, a 1958-1962 Chevrolet Shop Manual would be most useful. The 1958 and 1960 Shop Manuals would have the most complete Engine sections - they are full-description manuals (not supplementary manuals to previous manuals).
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