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| | | Forums66 Topics128,095 Posts1,056,468 Members48,444 | | 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!
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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: Apr 2004 Posts: 5,084 Authorized Pest | | Authorized Pest Joined: Apr 2004 Posts: 5,084 | Thanks to Sweet for sending this one in. As it starts: Didja know, on most Stovebolt Sixes, the oil pan must be removed to get the timing cover off? And if you DID know that, didja come by that knowledge the hard way?? They says true wisdom is learning from others' experience. If you ever want to get at your timing chain without all the drama of dropping the oil pan first, all you have to do is make an easy... Read the rest. Peg
~ Peggy M 1949 Chevrolet 3804"Charlie" - The Stovebolt FlagshipIn the Gallery"We make a living by what we get; we make a life by what we give." -- Winston Churchill | | | | | Joined: Sep 2006 Posts: 2,393 Shop Shark | | Shop Shark Joined: Sep 2006 Posts: 2,393 | Definitely a good tip that many of us have used. The only thing I would suggest is to use allen head bolts as opposed to hex head because there can be a wrench/socket clearance issue with the cover in installing and removing the hex head bolts. Using a handled allen wrench alleviates that issue.
Drew
| | | | | Joined: May 2012 Posts: 574 'Bolter | | 'Bolter Joined: May 2012 Posts: 574 | NOW you post this!!!! 
1949 Dodge Coronet 1955 2nd Chevy 4400 1.5 ton 1955 2nd Chevy 3100 1/2 ton 1955 2nd Chevy 3100 1/2 ton 1957 Chevy 5400 LCF 2 ton 1966 Dodge D100 Sweptline 1968 Chevy P20 stepvan 1969 GMC LWB pickup 1972 GMC Sprint 1974 CP30 shorty bus There are three things that I've learned never discuss with people: religion, politics, and the Great Pumpkin.----Linus Van Pelt Trying to understand the behavior of some people is like trying to smell the color 9 | | | | | Joined: Dec 2011 Posts: 402 Shop Shark | | Shop Shark Joined: Dec 2011 Posts: 402 | My word, but that's a nice-looking engine!
And, I might add, this tech tip work only cost me three beers (I think SWEET would have done it for two, but I'd have paid a case).
Looks great.
Jim
| | | | | Joined: Aug 2004 Posts: 1,418 ODSS Lawman | | ODSS Lawman Joined: Aug 2004 Posts: 1,418 | Well then, looks like I need to stop by for a few cold ones!!
SWEET Sergeant At Arms: Old Dominion Stovebolt Society BUNS?!?!?!Where we're going, we don't need no buns.....1950 GMC 450 1951 Chevy 1/2-TonThe GreenMachineIn the Stovebolt Gallery | | | | | Joined: Apr 2005 Posts: 396 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 396 | WHOA, just read the Tech tip and it says to use a 3/8 drill bit to drill and tap for a 3/8-16 bolt.Should this not read drill the holes to 5/16 inch and tap to 3/8-16? Jerry Jerry
| | | | | Joined: Apr 2005 Posts: 396 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 396 | OK, Here is what I found on the 235 block that I am getting ready to replace my 1951 chevy 216 engine and trying to follow the original posted tech tip. Will this mental torture ever end? The 2 lower bolts removed from Inside the pan threaded into the timing gear cover were 5/16-24 grade 5 bolts. When I fit a 5/16 drill bit shaft into those 2 block holes, it is sloppy loose.That is the bore size I would use to thread the 2 holes to 3/8-16 as per tech tip. Going up in size in drill bit diameter, I find that a 21/64 inch drill bit just fits the existing hole. looking at my US Tap and Drill Bit Size Table, that is the exact size needed for a 3/8-24 inch bolt. Please, I already drilled out the Timing gear cover to 3/8 inch. Is my block a misfit? Thanks to all for guidance! Jerry
Jerry
| | | | | Joined: May 2001 Posts: 7,438 Extreme Gabster | | Extreme Gabster Joined: May 2001 Posts: 7,438 | Only the cover needs to be drilled. The holes in the cap can be tapped as is, as 51 said above. | | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | Please read the tech tip carefully. It does NOT say to drill the bearing cap . Just the covers. | | | | | Joined: Jan 2013 Posts: 10 New Guy | | New Guy Joined: Jan 2013 Posts: 10 | I used to drill and make them removable from the front in the early 70's i also modified the front of the block to get the extra oil in the cover to drain back to the pan faster. This was easier than adding a fitting and drain line to get it back to the pan.I learned the oil drain trick from some of the old timers that raced these old engines on circle track and speed trap runs.
If you modify the block to drain the oil from your timing cover, the gears explosions will end and RPM will increase dramatically. My old 6 was built in the 70's at and has a lot of miles on it and has seen RPM's way over the normal range. | | | | | Joined: Aug 2012 Posts: 10 New Guy | | New Guy Joined: Aug 2012 Posts: 10 | I did this on my 59 GMC 270 with good results. With pan off, tapped with 3/8-24 unf, no drilling. Did this with everything bolted to the crankshaft as is.. afterwards i cleaned with brake/carb cleaner and sucked up the chips with a vacuum cleaner..
Just put a dash on gasket material on the new bolts so they wont leak, workes for gmc 270, i do not know if the hole sizes are different on Chevy's. | | | | | Joined: Apr 2011 Posts: 45 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2011 Posts: 45 | Are there any exceptions? When did they change this, or did they? Is my 66 like this too? I'm no engine guy but have a 53 GMC (Canadian) that has a leak up front. The engine is a Chevy. Can someone explain how to alter it to drain better, as it was mentioned in this thread? I would want to do that too, if I go in there.
All you can do is all you can do.
| | | | | Joined: Sep 2008 Posts: 872 Shop Shark | | Shop Shark Joined: Sep 2008 Posts: 872 | I did this mod... ended up drilling and going to a larger size bolt. After I tapped the main cap there was like 10-20% of the thread formed... was not happy with it since You need to have a decent torque to seal the cover.
Driller/tapped larger size no problems. | | |
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