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Old 06-04-2019, 04:38 PM   #1
chrisb9259
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newbie needing help.

bought a 72 c10 and replaced the starter and spark plugs and fortunately got her to run. but every time i pressed the gas the truck would die. being new to the mechanical situations and not knowing what i was doing. i replaced the distributor and replaced some gaskets in the carb. then when i started to crank it she started making an awful grinding sound. asked some people and found out i had the distributor 180 degrees out. not having any marks on my harmonic balancer i researched and figured out a solution. i took the valve cover off cylinder 1 and stuck screwdriver into #1 spark plug hole until i reached tdc. then did the math to make harmonic balancer tape. aligned the rotor with #1 cylinder and replaced spark plugs and wires. sounds better when i crank but still no start. i learned my lesson of doing too many things at once because now i dont know which is the problem. any help from this mess would be appreciated.
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Old 06-04-2019, 05:29 PM   #2
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Re: newbie needing help.

Do you have a timing pointer on the cover? I've ran into vehicles where they don't have one.

Also, depending on the motor, the timing marks may need to be seen from behind the water pump straight down (6:00)

The only mark you will have on the balancer is a single groove. Paint it white or get something inside of it so it can be seen.

When you pump the throttle does gas spray from the carb? If you pour some gas down the intake through the carb does it try and start?

Did you knock a wire off the coil somewhere?

Did you replace with an HEI distributor (coil built into the cap) and not run 12v directly to it? The external coil OE type only has about 6 volts because the power wire is a resistor.

I could go on and on, but this is the start.
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Old 06-04-2019, 05:44 PM   #3
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Re: newbie needing help.

v8 I'm assuming.

make sure when you replaced the distributor it dropped in all the way. It is tricky to do and easy to overlook the first couple of times. It has to engage in the flat keyway in the oil pump. You won't have any oil pressure otherwise!

The rotor should point right at the #1 cylinder at tdc. As long as no. 1 is lined up and you have the firing order right going clockwise you should be able to get it running.

Your original problem maybe the accelerator pump like already mentioned. If you get it going again and let the engine warm up for a while and it gets better, that's probably it.

Don't be afraid to move the distributor all around to get it to start. SBC are not that picky on timing to just get them running.
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Old 06-04-2019, 05:58 PM   #4
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Re: newbie needing help.

i replaced with hei distributor with coil built in. and i made sure the distributor fell flat into the grooves and into the oil pump line. i learned that the hard way the first time i tried to seat it. i do have a timing pointer. i was told to back seat the fuel pins of the carb all the way back. and i was wondering if it was flooding and also i believe the timing is on point. is there something im missing? and yes it is a v8 350 small block
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Old 06-04-2019, 06:02 PM   #5
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Re: newbie needing help.

Whatever you do, make certain that the distributor hold-down clamp is on top of the distributor base flange and that the distributor can't pop up. That's after you get it back into the oil pump drive shaft (if it is out, as has been mentioned). I've many engines locked up by missing that detail.
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Old 06-04-2019, 06:05 PM   #6
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Re: newbie needing help.

i also noticed that one of the prongs for the coil harness was bent but i bent it back and it is good. i tried to pour gas into the carb and still no start. what do you mean does gas spray from the carb? i have also tried to twist the distributor slightly when trying to crank but it tends to make the cfrank sound worse. thank you for all the help.
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Old 06-04-2019, 08:20 PM   #7
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Re: newbie needing help.

Quote:
Originally Posted by chrisb9259 View Post
i also noticed that one of the prongs for the coil harness was bent but i bent it back and it is good. i tried to pour gas into the carb and still no start. what do you mean does gas spray from the carb? i have also tried to twist the distributor slightly when trying to crank but it tends to make the cfrank sound worse. thank you for all the help.
Demian means that if the accelerator pump is working, it is possible to see a little spit/spray coming back out of the carburetor when you pump the gas. It won't be a lot, and it doesn't happen when the engine is running because air flow will carry it into the engine.
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Old 06-05-2019, 11:52 AM   #8
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Re: newbie needing help.

Quote:
Originally Posted by chrisb9259 View Post
i replaced with hei distributor with coil built in
Was it originally a points distributor with a separate coil?

If the answer is YES, then you need to run a new wire from a 12v source to the distributor for power (per my original response).
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Old 06-05-2019, 11:53 AM   #9
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Re: newbie needing help.

Quote:
Originally Posted by cashforclunkers View Post
Your original problem maybe the accelerator pump like already mentioned.
He did say he pulled the carb apart and replaced "gaskets".

If pouring gas down the carb doesn't cause a massive backfire or try to start, sounds like spark.
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Last edited by demian5; 06-05-2019 at 12:01 PM.
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Old 06-05-2019, 04:43 PM   #10
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Re: newbie needing help.

i will get help to see if i can test the accelerator pump. thanks for that. and yes i took the carb apart to clean the float bowls and such and one of the seals broke so i just replaced them all. i ordered new spark plugs wires and have recently replaced the spark plugs. i have made sure the hold down clamp was on the distributor flange. im at a loss here.
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Old 06-05-2019, 04:45 PM   #11
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Re: newbie needing help.

and i had replaced the hei distributor with a similar kind.
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Old 06-05-2019, 05:16 PM   #12
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Re: newbie needing help.

Quote:
Originally Posted by chrisb9259 View Post
and i had replaced the hei distributor with a similar kind.
Pull a wire and plug and leave the plug connected to the wire. Lay the plug on the frame for a ground and crank the motor - is the plug sparking?

Yes - Is it bright or dim?
No, check for 12V at the power wire coming from the ignition switch at the distributor. Also, make sure you have it plugged in properly, its easy to not be able to plug it in.

Also make sure its in the correct terminal and not the tach terminal.
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Last edited by demian5; 06-05-2019 at 05:29 PM.
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Old 06-05-2019, 05:30 PM   #13
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Re: newbie needing help.

Quote:
Originally Posted by chrisb9259 View Post
i will get help to see if i can test the accelerator pump. thanks for that. and yes i took the carb apart to clean the float bowls and such and one of the seals broke so i just replaced them all. i ordered new spark plugs wires and have recently replaced the spark plugs. i have made sure the hold down clamp was on the distributor flange. im at a loss here.
Pouring some gas down the carb into the motor will do the same thing as pumping the carb. It should have tried to start or popped if it was getting spark.
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Old 06-05-2019, 05:49 PM   #14
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Re: newbie needing help.

so i have a question. is there supposed to be a wire connected to the batt+ on the distributor cap? if so where does that come from? i dont remeber having to take one off of the old distributor.
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Old 06-05-2019, 05:58 PM   #15
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Re: newbie needing help.

Yup. Without it you have no spark. Power to that connector can come from a source on the fuse box that says "IGN UNFUSED". Buy the pigtail from the parts store so that you have a latching connector.
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Old 06-05-2019, 06:03 PM   #16
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Re: newbie needing help.

wow thats embarrassing. thank you. i will bet thats it huh.
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Old 06-05-2019, 10:24 PM   #17
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Re: newbie needing help.

It'll be a good start.
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Old 06-06-2019, 12:44 PM   #18
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Re: newbie needing help.

Quote:
Originally Posted by chrisb9259 View Post
wow thats embarrassing. thank you. i will bet thats it huh.
Rookie mistake, easy to fix. Post the burnout video after you get it running.
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Old 06-06-2019, 01:06 PM   #19
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Re: newbie needing help.

+1 for burnout vid
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Old 06-06-2019, 01:48 PM   #20
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Re: newbie needing help.

Quote:
Originally Posted by chrisb9259 View Post
wow thats embarrassing. thank you. i will bet thats it huh.
Don’t feel bad-I don’t know how many times I’ve tried to get an old truck running that I forgot to put the rotor back in....
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Old 06-06-2019, 05:39 PM   #21
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Re: newbie needing help.

so here is an update... i found the 12v power supply and plugged it into the dist cap. it tried to start a couple of times then it was still a no go. i think i need to adjust the needles for gas supply on carb because i backed them out quite a bit. maybe its flooding?? i dont know. anything you could recommend would be highly appreciated...
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Old 06-06-2019, 05:42 PM   #22
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Re: newbie needing help.

Try holding it to the floor while cranking (just until it starts and clears up) its probably flooded.

The idle screws can only make small adjustments and while it might not idle you should be able to get it running regardless of their position. I think there is a base line setting for those, Not sure.
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Old 06-07-2019, 06:34 AM   #23
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Re: newbie needing help.

Go with a base adjustment for the idle screws - turn them in til they just barely seat, then out 2 turns. Should be enough to get it running.

If it doesn't start after cranking for 30 seconds (and remember to only crank in 10 second intervals to avoid burning up your starter), then dump some fuel down the carb.

Verify you are getting spark. You can use a timing light while cranking. If it flashes, it's sparking.
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Old 06-08-2019, 06:03 AM   #24
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Re: newbie needing help.

I know too many cooks spoil the broth and all that. But when I first started tinkering with my 350 I was flooding my engine that badly I filled the sump up with gas. If your oil level is risen and stinks of fuel you know your getting plenty and it’s prob a ignition issue. But if there is too much down there may be best to give it an oil change. Just a side note, good luck
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Old 06-08-2019, 09:51 AM   #25
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Re: newbie needing help.

You can't flood the engine even if the idle mixture screws are removed. It won't run very well, though. As mentioned, check your oil for fuel before you go too much further. I think you need to have someone on-scene to help you.
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