Starting 250 after sitting a long time

[brian.kannady]

I'm hoping to start my 67 250 this weekend that has been sitting for 3 years or so. I got it from my Dad, and he doesn't have any idea when the oil was last changed. Last weekend, I emptied the fuel tank and put a new carb on (the old one was physically broken, leading to it being parked), and made sure the engine would turn.

Before I try and start it, I'm thinking that I should change the oil, and probably drop the pan and clean it out. I don't have an oil priming tool, is there something I should do to get oil back up into the engine before I try and start it? Any other advice? I'm planning on keeping this engine in it at least a couple more years, so I'd prefer to not tear it up..

[54blackhornet]

Brian, welcome to this forum! Pull the plugs and start by spraying a good amount of PB Blaster into each cylinder, reinstall plugs and let her sit for a few days. Pull valve cover off and check all valve train rockers to see that they are free, pour a little oil down all pushrods. I have started many GM 6cyl's that had sat for years with no major issues, just go slow and make sure the engine is free. If you pull the distributor to prime the bottom end , be sure you take notice of rotor position and mark the location of distributor body to replace it in proper location.....Good Luck
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[Ironangel]

Originally Posted by brian.kannady

I'm hoping to start my 67 250 this weekend that has been sitting for 3 years or so. I got it from my Dad, and he doesn't have any idea when the oil was last changed. Last weekend, I emptied the fuel tank and put a new carb on (the old one was physically broken, leading to it being parked), and made sure the engine would turn.

Before I try and start it, I'm thinking that I should change the oil, and probably drop the pan and clean it out. I don't have an oil priming tool, is there something I should do to get oil back up into the engine before I try and start it? Any other advice? I'm planning on keeping this engine in it at least a couple more years, so I'd prefer to not tear it up..

Here's what I do for engines that havent been run for years...Pull each plug and squirt a tablespoon or two of motor oil into each cylinder, clean that plug and replace it. Since you've indicated draining the old fuel from the tank(a very good idea!)and installing a new carb, I would also install an "metal inline fuel filter"...Changing the oil is also a good idea...I would add a 16oz bottle of "Marvels Mystery Oil" to the oil as well...Pull the coil wire and give her a whirl to get the oil flowing...Then replace the coil wire and "fire that mutha up"...Another bit of rarely mentioned fact is, these late 60's and early 70's flat tappet engines need zinc in the oil! "ZDDP" is a must for engine longevity...I run 15w40 Rotella T with a quart of Rislone ZDDP(zinc) additive...STP oil additive is the most cost friendly zinc additive on the shelf.I'll add this...Since its winter and cold, use 30w oil with Marvels Mystery Oil to clean things on the initial run because I would change the oil again shortly after the initial run, and install new plugs at this time, the thinner weight oil will flow more readily...My home made "Penetrant" 2 parts Tranny Fluid, one part Acetone, one part Diesel Fuel...Good luck!

[68gmsee]

As mentioned above, I did the plug removal then I used a small oil pump filled with regular 10W30 and squirted a few times in each cylinder. Cranked engine for several revolutions, reinstalled plugs and started engine.