Labor Day Putting down your wrenches or time for
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| | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | Finally got my 1955 1st Series 6400 with a 261 back on the road. Starts great, runs great with no hiccups or pops. When I come to a long grade, not really steep just long, I expect it to slow down but with the peddle smashed to the floor I continue to loose speed just to the point of having to down shift but not quite. Any thoughts on what might be the issue? Timing, carb, something else? I haven't checked the compression yet but did have a friend adjust the timing last fall. Any help or further questions would be fantastic.
Bruce | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | issue? I'd say you're learning what it was like for truckers back in the day  in a 1.5T truck when you'd see a grade ahead you mash the pedal well before you start the climb, and if you were loaded you'd be down shifting before the top even if you were speeding at the bottom Bill | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | I'm familiar with the "take a run at the hill" syndrome but this slows down really fast, faster than other trucks I've driven. At close to 60+ heading up the grade, I'd be at 20 very shortly with no load other than my gut! This should be a torque monster (for the day) with the 261. I'm going to borrow a compression tester from a friend and see what I'm at per cylinder. Something just doesn't seem right.
Bruce | | | | | Joined: Jul 2005 Posts: 640 Shop Shark | | Shop Shark Joined: Jul 2005 Posts: 640 | It could be the timing. I had a similar thing happen, and that's what it was. Good luck. | | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | I would also start with timing.
With today's gas these engines like a little more advance than called for.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | I would start with the timing also. The 261 &292 use a carb with a larger bore. Often when someone exchanges it for a "rebuilt" carb they wind up with one from a 235. That will cut the power down. It might be jetted too lean.
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: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | Good point about the carb size.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Aug 2005 Posts: 1,186 Shop Shark | | Shop Shark Joined: Aug 2005 Posts: 1,186 | Good point on the carb but it is the correct one for a 261. I have a stash of 261 carbs just in case. I don't have a timing light or vacuum gauge but I know people who do. I'll probably start there.
Bruce | | |
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