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| | | Forums66 Topics128,037 Posts1,055,470 Members48,424 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
| | THANKS!
For helping keep this great
old truck web site
on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | Here is a little information I gleaned from a previous thread. Hopefully others will add to it. The link is a copy of a tech bulletin concerning partial engines that had provision for a full flow engine. https://plus.google.com/10819770718...0762195122&oid=108197707187186692269The following is the little information that I can find about the 261. Hopefully others will share more. I think shop manuals remain silent on subjects like the dowels because it was not in the realm of Chevrolet dealers to do total rebuilds. 50 years ago there were hundreds of engine rebuilders around the country and GM considered them competition because they not only did the labor, but they installed aftermarket parts. GM wanted to sell now short blocks. And then there was another competitor of GM... the junk yards. Being a licensed salvage dealer for many years put me in that category. The Hollander states that casting No. 3759365 has the dowel. It clearly states that the doweled block fits all, but "Do not drive in the plug above the oil filter inlet hole. When driven in it is to be used with a full flow oil filter." The 261 was designed to be a truck engine, but the full flow setup just didn't work in trucks that were worked hard because of the rubber hoses under the exhaust became brittle from heat. 261 engines were very popular in their day with the guys that pulled cable dumps, but a lot of them bit the dust when they lost their oil. | | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | You can see what I have so far here: http://devestechnet.com/Home/TheVenerable261I am awaiting two things to add to it, the compression numbers from Tim and the detailed instruction on how to properly drill the 848 head for the 6 water jacket holes. This how-to is to the credit of many people coming together. I got info from an article called The Forgotten 261, added some inliners.org info and lots of great stuff from some of you. If you would be so kind as to read it carefully, and then tell me how to make it more readable, more correct, and more complete, lots of people out there greatly appreciate it. When its complete, I will gladly share it here as well.
Last edited by Deve; 02/27/2015 7:48 PM.
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | Kenneth,
I had to request access to your album. It is not viewable.
| | | | | Joined: Sep 2006 Posts: 2,393 Shop Shark | | Shop Shark Joined: Sep 2006 Posts: 2,393 | I got in it. Lots of nice truck pics and info along with family. Cute kid. Cute doggy. 
Drew
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | | | |
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