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Joined: May 2004
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The engine is a '61 Chevy 235.
What is the correct mark on flywheel for timing? I've been using the circle. I 've had the engine running great, then the next time I start it after cooling down it will run like crap. Is this a timing issue? or something else? I've been told I should be using the small mark just before the circle, and another source told me I should be using the triangle.
I've also been told the number one plug wire on the dizzy should be pointed more or less toward the front of the vehicle (3 O'Clock to 2 O'Clock range)right now it's at 12 O'Clock. Hoping you experts can tell me if I, or my information, or both are screwed up. Thanks


'61 Apache 10, '68 C-10, '82 C-30 Dually diesel. Pics at www.picturetrail.com/yachtcare
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The ball is correct.

If it runs fine one time, and not the next, I don't see how the timing would be an issue unless the dizzy is slipping out of adjustment??

Possibly the mech advance is sticky or the vac advance isn't working correctly, but the initial timing wouldn't change if the dizzy is clamped down in the block securely. The only other thing that comes to mind is if the camshaft has slid back out of the timing gear. This would throw off the initial timing...

Just what exactly does "runs like crap" mean to you? Are you running dual carbs and no manifold heat? Does it run fine after it warms up?


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Not running dual carbs, just stock Rochester "B". Have just replaced with a fresh rebuild from Advance, but wanted to figure what else may be problem before I tried starting it again, for fear of messing something up internally.
"Runs like crap" means... after adjusting the carb, and timing it will run smoothly for maybe a half hour or so(idling on the driveway). Then it starts to run rich, sputer, miss, blow black sooty smoke, you know, "run like crap". I can wait til the next day, when engine has cooled completly, and immediatley upon start up, it will "run like crap", just like it did when it ran warmed up the day before. At which opoint I get disgusted and let it sit for a month before I go fiddle with it some more to get it to run smooth again, only to have the same scenario played out. I did replace the heat riser spring, and the heat riser moves freely, but I have never seen the spring or heat riser do anything other than just sit there. As I'm in Florida, I dont know if the heat riser actually plays that big of a factor, but I have manually moved the riser while the engine was "running like crap", and it didnt make any difference. I have tested the Vac advance, it holds 9" as long as I want it too. The dizzy is clamped down tight. I am running a Pertronix module, but put the points back in just for the sake of testing it. Same thing either way. Maybe I should just try starting with the "new" rebuilt carb, and see what happens?


'61 Apache 10, '68 C-10, '82 C-30 Dually diesel. Pics at www.picturetrail.com/yachtcare
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There is a hole on the bottom of the carb that supplies vac to the power valve. If this is blocked, the power valve will always be down, which may lead to running rich. Make sure the carb base gasket has a slot in it that lines up with this hole.
It may also be that there is alot of junk in the gas, which may cause the needle to stick open and dump fuel. How does the fuel filter look?


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As stated, I just replaced the carb with a remanned unit, as the old "B" kept leaking even after I put two kits in it, and swapped the throttle body. I didnt notice a slot in the old gasket when I removed it, but that doesnt mean it wasnt there. The new gasket that came with the remanned unit did have a slot(s), which prompted me to notice the vac openings. I havnt tried starting it with the new carb yet.
Fuel tank, sending unit, lines, fuel pump are all new and clean. I have two filters installed one right before the fuel pump, and one right before the carb. Both are clear and clean.
As I get time later this week, I'll break out the timing light and vac gauge, check adjustment on valves again, tune the new carb and see what happens with a fresh set of plugs.
Thinking the carb may have been the real culprit. Thanks for the help.


'61 Apache 10, '68 C-10, '82 C-30 Dually diesel. Pics at www.picturetrail.com/yachtcare
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Another thing would be the choke. If it is an auto choke, it could be staying shut which would cause it to run rich.


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