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| | | Forums66 Topics128,180 Posts1,057,150 Members48,464 | | 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!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Nov 2018 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2018 Posts: 44 | Dear Friends: I brought a used 235 engine 6 months ago. It has all the accessories installed. I stored it upright in a climate controlled garage. There was oil in the crankcase. The crankshaft turned freely using just the fan and I last checked it 3 months ago. When I started to work on it this week end, , the engine is locked just as if it were bolted. Turning the damper with a pry bar fabricated for the purpose will not budge it either way, not a fraction. I pulled the pan and it is beautiful under there with an oil film covering everything. I pulled out the distributer and gear and removed the spark plugs and liberally sprayed in penetrating oil.
What could be causing this?
Best regards,
Joe.
Last edited by Joe S.; 05/28/2019 1:09 AM.
'49 3100 "Sweet Caroline" because the truck has fabulous curves .... like Caroline!
| | | | | Joined: Feb 2004 Posts: 29,875 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,875 | Piston rings rusted to the cylinder walls, and/or valves seized in their guides. Pour a few ounces of Diesel fuel into all of the cylinders, and loosen the valve adjusting screws a couple of turns each. If the flywheel is still bolted to the crankshaft, use the chisel-shaped end of a long shepherd's crook wrecking bar between the starter gear teeth and the edge of the bellhousing. You can get a lot more leverage on the crankshaft that way, and you'll probably break the rusted rings loose. While you're at it, figure out a way to pry the rocker arms down against the valve stems a little. That will determine whether or not you've got seized valves. I'm betting on piston rings.
No matter where an engine stops turning, there will be a few valves open. This allows air (and humidity) to cycle in and out of those cylinders as the temperature changes. Next time you store an engine, put a few ounces of motor oil into all the cylinders, and then plug off the intake and exhaust manifolds or the ports in the head with duct tape to keep air from getting to the cylinders. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Nov 2018 Posts: 44 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2018 Posts: 44 | Thanks Jerry, you have helped me a lot on this build.
'49 3100 "Sweet Caroline" because the truck has fabulous curves .... like Caroline!
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | One of the benefits? of living in the 'rust belt.'
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires. '47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle. '54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed. '55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | Sometimes mice will get into the cylinders and have a potty break. There pee is very corrosive.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Dec 2021 Posts: 2 Moderated | | Moderated Joined: Dec 2021 Posts: 2 | Merry Christmas, I have just recently converted my 235 to electronic ignition. It idles fine but at acceleration it falls on its face. I have called the tech from Pertronix to get some insight and he suggests a bad ground between the distributor and ground. Any suggestions? Thanks | | | | | Joined: Mar 2010 Posts: 10,307 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,307 | If you have points and condenser, install them to see if the problem goes away. If it does, its your choice whether to go back to Pertronix.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Sep 2012 Posts: 222 'Bolter | | 'Bolter Joined: Sep 2012 Posts: 222 | ApacheJr: I've had 2 Pertronix units fail with those same symptoms. Was very frustrating trying to diagnose. Will not use Pertronix anymore. Dave
Last edited by DaveV; 12/26/2021 3:55 PM.
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