I just completed putting in a new 350 in my '71 chevelle. The last step is my new distributor. I know I have to find top dead center, TDC, first, but I am not sure how this is done. Can someone walk me through the steps of putting in a new distributor??? Any help would be appreciated as my manual is kind of vague.
Dropping in new distributor------Question????
Dennis Strawley
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I just completed putting in a new 350 in my '71 chevelle. The last step is my new distributor. I know I have to find top dead center, TDC, first, but I am not sure how this is done. Can someone walk me through the steps of putting in a new distributor??? Any help would be appreciated as my manual is kind of vague.
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Turn the crankshaft with a wrench with the #1 plug out. Put your index finger over the plug hole till you feel pressure. Look at the timint marks on the timing cover, and line the marks up at 0°. Drop the distributor in any ole way but be sure that the vacuum advance doesnt hit the valve cover when you do. When the distributor seats alla way down, the rotor will be pointing some direction. Look at the cap to determine which terminal the rotor is closest to. This will be your number one terminal. Rotate the dist housing until the rotor is pointing directly at this terminal. snug the distributor clamp bolt. Arange the wires in a clockwise fashion starting with number 1 8 4 3 6 5 7 2. Then attempt to start the car. if it is hard to crank (slow) then twist the dist in a clockwise manner until it cranks easy and fires. If it is easy to crank but wants to stall, rotate the distributor in a counterclockwise manner until it is just a bit hard to crank, then start it, and ck and adjust the timing with a light.
HTH
HTH
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When installing the distributor, you may notice that it stops a little short on the way down. That means the oil pump drive isn't aligned. Put the hold-down clamp in place. Tighten the bolt until snug just so you put a little downward pressure on the distributor. You may have to temporarily use a slightly longer bolt. Don't go nuts tightening it either. Once you've snugged it down, turn the engine. The distributor will fall into place. Bring it back to TDC compression stroke, install correct length hold-down bolt, and rock on with the ignition timing
The other thing you can due to engage the oil pump without turning the motor over is if the distributor doesn't go all of the way in at first, pull it back out enough to disengage the cam gear, them turn the rotor ahead slightly (the goal is to move it ahead by one tooth width on the gear), then try pushing it down again. Repeat until the distributor sinks all the way in by hand. You shouldn't need to put force on it with the hold down if you use this method. Might take a little longer, but you don't have tore-find TDC.
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Steve
72 Chevelle SS402/4sp
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Steve
72 Chevelle SS402/4sp
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The oil pump drive and the rotor point in the same direction. If you use a long standard screwdriver to point the oil pump driveshaft slot to where the rotor points as it engages the cam gear, the dist will drop right in.
HTH
HTH
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You're thinking Ford or Chrysler. Chevy uses a hex type pump drive. And it really isn't as complicated as it sounds, Dennis. Most folks I know will get the distributor down to the pump shaft and simply hold pressurte on it by hand while a helper bumps the engine with the starter. You just have to be careful that the turning rotor doesn't catch your skin. (It's best to remove the rotor for this step.) It seems like every time I do this though, there's not another person within 50 miles, so I have to use the clamp to put pressure on the distributor while I bump the starter. This isn't really hard at all, it's just a little intimidating if it's your first time. It's not that hard to get it back to TDC compression. You'll probably find that turning crank over to the TDC mark and then one additional revolution will do the trick, if you didn't have to turn the several times to engage the pump. It usually pops right in with a couple of bumps.
One little trick I like to use to find TDC compression stroke:
I like to remove the driver's side valve cover and rotate the engine while observing the rocker arms. Be sure to rotate the engine in its normal direction of rotation. Turn the engine by hand until the exhaust rocker opens and closes. Continue turning. You'll see the intake rocker start to move as the exhaust valve is closing. Turn the engine until the intake has closed. Now take your eyes off the rockers and start watching the timing mark on the timing cover. Continue turning the crank slowly and soon you'll see the mark on the damper coming up. Rotate the crank until the mark on the damper is aligned with the TDC mark or "0". There's a lot of different ways to do the same job. Find what works best for you
One little trick I like to use to find TDC compression stroke:
I like to remove the driver's side valve cover and rotate the engine while observing the rocker arms. Be sure to rotate the engine in its normal direction of rotation. Turn the engine by hand until the exhaust rocker opens and closes. Continue turning. You'll see the intake rocker start to move as the exhaust valve is closing. Turn the engine until the intake has closed. Now take your eyes off the rockers and start watching the timing mark on the timing cover. Continue turning the crank slowly and soon you'll see the mark on the damper coming up. Rotate the crank until the mark on the damper is aligned with the TDC mark or "0". There's a lot of different ways to do the same job. Find what works best for you
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Define what is meant by "chevy uses a hex drive"
I have been a mechanic for over 20 years ,, and just built my 440 Dodge engine which has a hex drive shaft for the oil pump drive as does Ford ,, Chevy has a drive that will accept a flat blade screw driver like Blown 406 says ,, simple holding down on distributor while someone cranks engine will work fine ,, there are several ways to bring disributor down fully ,, if you are useing store bought ready made wires you may want to look in shop book and locate #1 on cap and point rotor to that position ,, once you have droped dist. in and have to crank it to make it fully drop ,, dont worry nothing has changed with your timming ,, just remember to mark were your #1 was
I've been turning wrenches for 25+ years and have never seen a hex drive oil pump on a Chevy...live and learn I guess.
Any way, my .02 on dropping a dist. is to find TDC as outlined above by Blown 406, with the additional advice of pulling the valve cover on the odd side(expose #1). With it off, you can watch the #1 intake close as #1 comes up on compression. As far as aligning the oil pump drive and where #1 should point from the rotor, it's been my experience that when in time the oil pump drive slot should be aligned straight from front to back with the C/L of the crank. Since the dist gear will turn a little when it seats, the oil pump drive usually aligns well when it is preset(with large screwdriver) at the 1&7 o'clock position. When done correctly, your distributor should seat with the rotor pointing roughly at the #4 sparkplug. A little twisting back and forth in between start attempts should get you close enough for the timing light to finish the job(although I never used one while racing, but that's another story
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).
Bryan
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'65 Malibu frame-off project(slow going!)
'70 C-20 Longhorn p/u (daily driver)
Any way, my .02 on dropping a dist. is to find TDC as outlined above by Blown 406, with the additional advice of pulling the valve cover on the odd side(expose #1). With it off, you can watch the #1 intake close as #1 comes up on compression. As far as aligning the oil pump drive and where #1 should point from the rotor, it's been my experience that when in time the oil pump drive slot should be aligned straight from front to back with the C/L of the crank. Since the dist gear will turn a little when it seats, the oil pump drive usually aligns well when it is preset(with large screwdriver) at the 1&7 o'clock position. When done correctly, your distributor should seat with the rotor pointing roughly at the #4 sparkplug. A little twisting back and forth in between start attempts should get you close enough for the timing light to finish the job(although I never used one while racing, but that's another story
Bryan
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'65 Malibu frame-off project(slow going!)
'70 C-20 Longhorn p/u (daily driver)
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My mistake, total brainfart. It is slot drive. I had it ass backwards. After I shut off my computer and watched TV for about an hour, I suddenly asked myself, "What the hell did I tell Dennis?" And that's with my own 25+ years, time spent working for GM dealerships, ASE certifications and whatnot. Sometimes it jumbles together as I have also spent time at Ford and Chrysler dealerships. But anyway, I still use the method I described to get the distributor down that last 1/4 inch. They usually pop in in less time than it took for all of you to catch my goof. But if you have a helper holding it down, be sure he holds it by the housing and do not put hands and soft skin anywhere near the rotor. What can I say? It's worked for me for years. To each his own. You've all got to find a way that works best for you. Thanks to Bryan, Catman, and Camino for not letting me lead Dennis astray. I've banged my head against the wall at least 20 times. Now where did my computer mouse go? And why is the room spinning
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By the way, yes I am a well seasoned and experienced mechanic. Yes, I am good, damn good. No, I still haven't figured out what the hell I was thinking. Sorry Dennis. I've e-mailed each of you, I hope we got it straight, and I hope I'm not losing gray matter.
[This message has been edited by Randy Mosier (edited 11-27-99).]
[This message has been edited by Randy Mosier (edited 11-27-99).]
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Thanks guys. And Dennis, since this your thread, be sure to keep us updated and let us know if you need any more help.
Randy; let me guess - you have passed that magic 40th birthday. The memory is the first to go. I am living proof. Don't worry, it will get worse till you no longer can remember that you forgot anything at all. At that point all is OK again. (ignorance is bliss)
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Gotta have a Chevy !In Durham N.C.
Why is there never enough time or money to do it right the first time, but ALWAYS enough to do it over?
Make it look the way you like it, forget what the other guys say!
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Gotta have a Chevy !In Durham N.C.
Why is there never enough time or money to do it right the first time, but ALWAYS enough to do it over?
Make it look the way you like it, forget what the other guys say!
Dennis, a quick word in reguards to safety. When dropping in a distributor and your unsure exactly where the timing is at on the engine, put the air cleaner back on the carb before you attempt to fire the engine for the 1st time. If the timing is retarded the engine might launch a fire ball back through the carb. Just my .02, Rob
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66, Been there, done that. Did you know that it takes 2 months for eyebrows to grow back? Can't tell you about the hair, that part had retreated to a safe distance years ago.
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Philip Valentine
Lakeside, AZ
Member #42 GOLD
"Perseverance is not a long race; it is many short races one after another."
philip@chevelles.com
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Philip Valentine
Lakeside, AZ
Member #42 GOLD
"Perseverance is not a long race; it is many short races one after another."
philip@chevelles.com
Dennis I would follow Catman's advise to aim the rotor to where the factory manuals place the # 1 spark plug wire. It always bugs me when trouble shooting non running motors when people don't have # 1 where it should be. Makes you wonder what else is messed up.
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283, you're a perceptive individual. 41 to be exact.
Youth and enthusiasm will eventually give way to middle age and cynacism.
Youth and enthusiasm will eventually give way to middle age and cynacism.
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