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Driving on freeway
Truck shuts down
Get pulled over onto city street. Find the distributor cap off and distributor moved.
Move the distributor back to under #1
Get her started pulled away carefully and heard a thumping sound. Called tow.
I'm not much of an engine guy. When I get her home what should I look for?
I don't know why the cap fell off while driving? Or if that was the cause or effect
Thanks
1954 235 z motor. 216 manifold
Last edited by Peggy M; 07/01/2024 7:01 PM.
| | | | | Joined: Apr 2014 Posts: 924 Shop Shark | | Shop Shark Joined: Apr 2014 Posts: 924 | Was it thumping before it shut down, or only after you replaced the distributor cap & got moving again?
You can pull the distributor all the way out and check its drive gear that interfaces with the cam & check the slotted end that drives the oil pump. Just to make sure no pieces are missing/broken.Something there may not be meshing correctly. I'm not sure if the distributor could worm its way out if it was not secured or properly seated.
That stinks, man- but good call on the tow truck after hearing the thumping noise! My curiousity would have me dropping the oil pan, too.
Brad Wrench Fetcher, PhD | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Was it thumping before it shut down, or only after you replaced the distributor cap Didn't notice any sounds while I was driving. I was going about 50mph Only noticed the thump sound once I got her restarted So I was going about 50 on the freeway, truck shuts down, able to coast off onto the streets, open hood and find distributor cap off and the distributor had moved off time. Ill check the distributor first. Very strange to see the distributor cap laying to the side. ... ... | | | | | Joined: Sep 2006 Posts: 2,393 Shop Shark | | Shop Shark Joined: Sep 2006 Posts: 2,393 | Were any spring clips broke? Maybe someone messing with your truck when you weren't looking? I had the distributor gear pin shear one time and that changed everything where timing was concerned.
Drew
| | | | | Joined: Aug 2012 Posts: 1,214 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 1,214 | Perhaps the dist shaft bearing became worn/loose enough to allow the shaft/rotor to wobble enough to cause the rotor to contact the cap, knocking it off. The thump could have been when the rotor contacted the dist cap. What may have originally caused it to die was the wobbly shaft not opening/closing the points.
Hopefully it's something minor such as that.
Good luck Dave | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | no, the springs were in place I just had a chance to remove the distributor the grease cup was jammed up against the cover ...pic... I had to pry it up to get it out. the distributor has a grinding sound when turning ...video... and it looks like a nut is missing from that plate? Checked the oil pump and it moved freely. here is something else ...video... not a good day | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | bearing in the dizzy seized up, maybe a few years without the grease cup attended to ..... life is fulla bumps
Bill | | | | | Joined: Aug 2012 Posts: 1,214 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 1,214 | In your 2nd video, sounds like the rear brake shoes are causing the moan. My 49 makes a similar noise when I roll it around in the shop every now and then. Does you parking brake stick sometimes? That missing nut is probably the cause of your engine related problems. You'll have to either rebuild/replace the dist.
Although it broke down on you, it's appearing you dodged a major bullet.
Good luck Dave | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | It could be that the bearing seized. The gear looks in good shape. Just called napa. The distributor I pained 80 bucks for 4 years ago now goes for 180. Ouch!
Thanks for commenting on the second video. I had not heard that before on my truck. Maybe I'm a little skittish.
Ill get a good distributor in and start from there
Thanks | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Ok napa had a distributor but wanted 190.00 Rock auto has one for 81.00 but four days out I have an old one with a loose gear I think I'll try to repair I've read they can be re pinned with a roll pin Anyone know the size of pin? ...pic... Ill try my local hardware store but not sure if it need a hardened pin or just any spring pin Thanks | | | | | Joined: Oct 2012 Posts: 233 'Bolter | | 'Bolter Joined: Oct 2012 Posts: 233 | Sorry for your missfortune. The pin is 3/16 (to my memory)
1953 Chevy 3100 261 and SM420 53Chevy 31001953 Mack Firetruck 1972 Porsche 911 1986 Honda Goldwing
| | | | | Joined: Nov 2010 Posts: 1,159 Shop Shark | | Shop Shark Joined: Nov 2010 Posts: 1,159 | | | | | | Joined: Feb 2004 Posts: 29,881 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,881 | Since the pin carries all the load of driving the oil pump, I don't think I'd want to take a chance on a spring steel roll pin- - - -too brittle. This is going to sound really shade tree, but if you drill out the gear and the shaft with a set of number drills until it's a very snug fit for a piece of a 20 penny nail, and then peen the ends well, there will be zero slack and there will be much less of a chance of developing slop in the distributor drive. The nail is tough, not hard, and it takes the shock of driving the oil pump much better than a hardened pin. 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: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Thanks for the info HRL I had already went to lowes and got the 3/16 pin Hopefully I can get this old distributor to work temporally so I can get the 50 started and continue my troubleshooting in the garage. Fortunately wetwill5757 made me a generous offer. Thank you So here's the old distributor with the pin installed. The drive gear is not loose anymore. ...pic... I do have some up and down slop Is this acceptable? ...video... | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | That up and down slop looks about right. When the distributor is installed this will be eliminated as the gear rests against the top of the oil pump and the housing will be pushed all the way down.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Aug 2012 Posts: 566 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 566 | Hey DADS50
I have my old distributor in my garage so if you need it to trouble shoot I can loan it to you. The motor it came from is a 1956 235. I think the cam gear that drives the dizzy might be different but if your motor is a little newer and if it fits you are welcome to it. I am in Henderson.
Just let me know.
"As I lay rubber down the street, I pray for traction I can keep, but if I spin and begin to slide, please dear God protect my sweet ride." -Amen 56 Chevy 3100 | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Thanks for the offer I repined and old distributor I had with a loose gear last night and drop that in today after I drop the boy off at school.
Not sure when the change in drive gears came?
| | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Thanks for the link Looks like I have an early 54.
Edit
Last edited by DADS50; 10/07/2014 8:21 PM.
| | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Here's an update for today
Installed my old distributor that I repined last night. Was having a heck of a time getting her started.
Lost my time. When I finally got her starting rough I was showing 30 degrees advanced.
Took a break, reset the distributor to about 14 degrees advanced (pertronix) Started to idle better. Set the rpm to 450. Could only get about 17 inches of vacuum.
So she starts and idles ok, I'm hearing an exhaust sound out the tail pipe I didn't hear before.
So next I'll reset the valves Then drive her out of the garage to see if there are any other issues.
She's not running as nice as she did before. But at least I'm not hearing the lower end nock I thought I heard on the side of the road.
Not fun loosing a distributor cap on the freeway going 50mph
Thanks of all the help so far. I'm sure ill need more help soon.
| | | | | Joined: Aug 2000 Posts: 1,438 'Bolter | | 'Bolter Joined: Aug 2000 Posts: 1,438 | I wonder if the timing chain jumped a tooth.
Dennis
40 Chevy 1/2 ton
| | | | | Joined: Sep 2001 Posts: 29,270 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,270 | 1954 235 z motor. 216 manifold
There is no timing chain.
| | | | | Joined: Aug 2012 Posts: 1,214 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 1,214 | I've heard an engine knock like a rod was going to bust out of the block due to being advanced too much.
You could still be advanced too much. You'll get it right.
Dave | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | yeah I didn't get a chance to get the the valves today, or pull her out of the garage. here's a video of when I thought I was set at #1 ...video... In that video the gun says 42 degrees advanced. I was a little lost at that point. after that I moved the distributor back to about 12 degrees advanced. she started and idled much better. Played with the carb settings a little. At least shes running a little better but I'm still not there. I probably wont get to play with this till Saturday. More to follow | | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | http://www.almabolt.com/pages/catalog/pins/springroll.htmSpring type roll pins are a good answer here, but like Jerry eludes to, not something I would feel good about in the long run, but this website talks about putting a roll pin inside a roll pin. I just rebuilt 2 distributors using this method and the gear is tight, and I cant imagine with the force pounding the 2nd one in, anything ever happening concerning that gear again. | | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | I would be more worried about damaging the gear beating in the second roll pin than I would worrying about one roll pin shearing off. | | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | I don't think that's an issue Don. The force isn't THAT much. It's just good insurance. | | | | | Joined: Nov 2010 Posts: 1,159 Shop Shark | | Shop Shark Joined: Nov 2010 Posts: 1,159 | Good News,"Dad's50"!! You should have your "Dizzy By Saturday,just in "time"!! Hope it works for ya!!
Last edited by wetwilly5757; 10/10/2014 8:21 AM.
| | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | I guess I was interpreting your post wrong Deve.
"I cant imagine with the force pounding the 2nd one in, anything ever happening concerning that gear again."
| | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | It was a nice addition, that second pin because you could see how much pressure it took to get the second one in. Nothing like the force of pounding a taper pin in place or anything. It wasnt my idea, but I sure am glad someone thought of it. | | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | What grease do you use in the grease cup of the distributor?
I have been using red wheel bearing grease. But I noticed on the bad distributor I just took out the trucks that the grease looked to have caked up.
Any recommendations?
I do have a tube of general purpose grease but don't know it it will Break down | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I use Lubriplate 630-AA, but I think chassis grease would be okay.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Dec 2000 Posts: 3,399 Gas Pumper | | Gas Pumper Joined: Dec 2000 Posts: 3,399 | Chassis grease is what is common, but Lubriplate is my favorite grease. I use their products for engine rebuilding and its definitely what I would put in the dizzy cup. | | | | | Joined: Mar 2010 Posts: 10,310 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,310 | I use Vita Power Specialized Lubricant, 2T3501 Cup Grease, Western Auto Supply CO. "A calcium based lubricant for distributor grease cups". I do not know where I got it, and I don't know if it is still available. It looks like wheel bearing grease and could very well be just that. They had skilled marketers 60 years ago. Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Jan 2010 Posts: 4,263 Shop Shark | | Shop Shark Joined: Jan 2010 Posts: 4,263 | Well Finally had a chance to work on the truck. It was a long day. But I finally got a distributor installed. Pulled her out of the garage and didn't notice any drivetrain issues. Have not done a road test. Ran out of time. She still is not idling as good as she did before the mishap ...link... Also, before I could idle at 450rpm. Now It runs better at 500 RPM | | |
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