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| | | | Joined: Dec 2006 Posts: 1,154 Shop Shark | | Shop Shark Joined: Dec 2006 Posts: 1,154 | Hi.....I understand that a lean condition will cause pops on a downhill on compression. So I turned the screw at the base of my Rodchester B out about 1/2 turn from where it was set and it helped...but.....how much is enough. I'm afraid of losing the spring and needle. I have the engine tuned by the vacuum method and the needle is steady at 19 at 2800 foot elevation and about 650 rpm idle. She runs a treat but when on compression down a hill I get those small rumble farts which my wife hates. Thanks in advance for your help to us.
Steve
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Its true, richening the mixture will solve or help it. If you want to tighten the spring on the needle valve you can add a flat washer or 2 behind it but if you only have 1-2 threads left you will need to turn it in a little. A different muffler might help.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Aug 2004 Posts: 1,418 ODSS Lawman | | ODSS Lawman Joined: Aug 2004 Posts: 1,418 | Simple.
Press clutch in on downhill (if the grade isn't too long) and pops go away.
Or do what I do and when it pops, tell her its the Jake brake!!
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: Feb 2008 Posts: 202 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 202 | It sounds like you are getting air into the exhaust system, But first make sure it has a full tune up. To check for exhaust leaks with the engine idling start at the head to exhaust manifold joint look and listen for leaks and work your way back to the end of exhaust pipe. Pay close attention to the connections before and after the muffler, Make sure that you have a tail pipe to the rear bumper or tailgate, if nothing else it moves the pops and farts to the back of the truck.
Keep the 216's running. 1949 1/2 ton model #1314 (US 3104) Brian
| | | | | Joined: Mar 2010 Posts: 10,301 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,301 | What kind of exhaust system are you running?
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Feb 2001 Posts: 1,094 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,094 | Check the timing, and look for an exhaust leak, like others have said.Doesn't take much of a leak to do what you describe.
Tommy
59 apache 1/2t
261 short stepside
| | | | | Joined: Dec 2006 Posts: 1,154 Shop Shark | | Shop Shark Joined: Dec 2006 Posts: 1,154 | Thanks all for your ideas. I will check out all the items that were suggested and report back. The exhausted a split manifold was done by the PO the weld is tight and there are no holes in the system. I think I will re-time the engine to the BB and see what gives. Timing to the BB may produce knock so maybe a few degrees before the BB??..We have an adjustable timing light. Mr. Langdon suggest 10 BTDC but our 235 is not happy with that set-up.
Thanks, Steve
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