No fire for 71 c-10 350 with new carb

[colbyclay]

Hello all,
My dad and I are trying to get our 71 c-10 back up and running. One year ago we got it running after about 10 yrs of sitting idle. Everything was going well until we noticed that there was gas leaking out of the side of the carburetor pretty badly. We tried rebuilding the carb ourselves and that didnt work out too well, so we ordered a rebuilt 4 barrel (same as what was on it). Dropped in the new carb, which was pretty easy. Went to start it, got one very loud backfire, the nothing. It is turning over well, but not starting up. Trouble shooting so far:
We are getting gas to carb, choke is opening/closing.
Changed points, condenser and coil.
No spark from new coil, even when hook up directly to the battery. Checked to see if wires were hot using small screwdriver like device with a light bulb. Power to both post of coil as well as inside post. Power to points.

Looked on the forum and noticed someone saying that it might be the distributor, but if we arent even getting fire from the coil when it is hooked up to the battery, could this really be it?

Any ideas?

Thanks

[BIG69GMC]

not sure about going direct to the battery with the coil but i would leave it installed where it is supposed to go and start checking for spark at the plugs to the plug wires, have someone crank it while you hold the spark plug boot close to the end of the spark plug and you should see the spark jump from the wire to the plug (hold it just off the plug but as close as you can to the plug being still able to see it spark) then if no spark check the same at the dist. on the spark wire that goes to the coil. (disconnecting it at the dist. and having someone crank it while you check.
also check for 12v power at the coil and for ground.
hope this helps get you pointed in the right direction, dave...

[colbyclay]

Originally Posted by BIG69GMC

not sure about going direct to the battery with the coil but i would leave it installed where it is supposed to go and start checking for spark at the plugs to the plug wires, have someone crank it while you hold the spark plug boot close to the end of the spark plug and you should see the spark jump from the wire to the plug (hold it just off the plug but as close as you can to the plug being still able to see it spark) then if no spark check the same at the dist. on the spark wire that goes to the coil. (disconnecting it at the dist. and having someone crank it while you check.
also check for 12v power at the coil and for ground.
hope this helps get you pointed in the right direction, dave...

Thanks Big69GMC,
We did that as well. No fire to the plug, no fire to the distributor from the coil. We charged the battery to full just in case it wasnt giving enough juice. I dont have a multimeter, but we checked to see if it was hot using the little screwdriver like device. when hooked up normally as well.

[hayhauler71]

little screwdriver like device.

It is called a test light

[cdowns]

did you set the gap for the points?

[colbyclay]

@hayhauler71: Well that makes sense, now doesnt it?

@cdowns: Yes, the points were set to .19 (I read that somewhere)

[colbyclay]

Any ideas why we wound not get any spark after changing out the carb., points, condenser and coil? Am I missing a grounding wire somewhere?

[truckdude239]

.19 dont sound right to me

[hayhauler71]

Put your test light on the neg side of coil and the other side to battery ground and have someone crank the engine. The test light should flash as the points open and close. If no flash the problem is in the distributor[ points, condenser]

[colbyclay]

Hi everyone,
So today we replaced the distributor after setting the new points. Still nothing. To date we have replaced the condenser, distributor and carburetor. We can turn the engine over, and the carb is getting gas, but it never starts. I am completely stuck. Does anyone have any ideas?
Thanks
Colby

[Youngbuck7072]

how much gas is the carb getting? I would take off the fuel line and put it in a plastic bottle, then turn the key to the right(just to get the fuel pump going) and see if it flows freely. you might need a new fuel pump. and is the carb BRAND NEW or did you get it secondhand?

[colbyclay]

Originally Posted by Youngbuck7072

how much gas is the carb getting? I would take off the fuel line and put it in a plastic bottle, then turn the key to the right(just to get the fuel pump going) and see if it flows freely. you might need a new fuel pump. and is the carb BRAND NEW or did you get it secondhand?

The carb was a referb from Rochester (quadrajet) that I bought through LMC.

Gas is coming out well from the fuel line. It was coming in pretty good spurts (aka not a constant flow).

[Kurt L]

how bout the timming chain gears? have you brought number one up to see if it lines up with number one on the cap?

[colbyclay]

Originally Posted by Kurt L

how bout the timming chain gears? have you brought number one up to see if it lines up with number one on the cap?

No, we havent done that. If we lined up the new distributor with the old one, would we need to worry about that? Wouldnt they be in the same position?

[Youngbuck7072]

should be a contant flow. i would get a new fuel pump, just a precationary measure and try it out, they are only like 25$( i have a fuel pump that goes along the fraim rail under the cab, i dont know how much one is that bolts on to the block

[long67]

It will never run without spark at plugs. You need to go thru the distributor and make sure everything is good ,set right and connected then retime motor and distributor by bringing number one cylinder to top dead center and installing distributor correctly.

[jay6891]

I suspect a broken timing chain.Have you checked to see if the rotor is even turning? Take cap off and watch while someone is cranking engine. If good, then pull #1 plug, put finger over hole while someone bumps the starter. When air blows out plug hole, your at #1 top dead center. Look and see if #1 plug wire is in same position as rotor. If not pull dist and roll around till it is and reinstall. Hope it helps Buddy

[swamp rat]

Originally Posted by colbyclay

@hayhauler71: Well that makes sense, now doesnt it?

@cdowns: Yes, the points were set to .19 (I read that somewhere)

I hope ya ment .019, .19 is way too wide, don't know that points will even go that wide, I used to use a match book cover when i was a youngster, it worked.

READ: If you had a backfire you HAD spark.

If you can squirt fuel out of the carb by rocking the throttle then you don't need a new fuel pump, don't throw money at something you don't need to, better to systematicly troubleshoot the problem. pulling the hose to see if fuel squirts into a containor is the best way to know it works.

Check compression in a cyl with a compression guage. if you have compression you don't have a broken timing chain..

You do need to make sure the roter is aligned with the #1 position on the cap when the #1 cyl is at top dead center, see link below....

Per the previous post when you ( or your dad) bump the engine over with the #1 plug out and with a finger over the spark plug hole and start to feel the air being pumped out of the spark plug hole you need to hand turn the engine to line up the timing marks, its advisable to have someone else turn the engine by hand while you have your finger on that hole and make sure you feel the air being forced out as the timing mark is getting close, that is when your at TDC on the #1 cyl, then check the alignment of the roter and cap. Make sure also that you have the correct roter and that it will not spin on the shaft, i have gotten the wrong roter before and it would go on but could move side to side..

http://www.google.com/imgres?imgurl=...t:429,r:4,s:58

[El Jay]

For a rough check you can just bump the engine around until the timing mark on the harmonic balancer is somewhere in the neighborhood of 8-0 degrees BTDC on the pointer.
Use a Sharpie, or Marks-A-Lot and put a mark on the distributor body below the #1 tower on the cap.
Lift the cap & the rotor should either be pointing at your mark on the distributor, or 180 degrees out (#6). If it is pointing to #6, you can roll the engine over 1 more revolution to get the rotor around to #1.

If the rotor is pointing where it should be, that's close enough for it to start, if it's firing.

I know this all sounds rather crude, but we're not building a Rolex, rather just trying to get a SBC to fire.

[colbyclay]

Sunday, we were able to get the truck started. We were able to do a rough, and I mean rough adjustment of the timing. We are going to get a timing gun soon to actually get it set correctly. We drove it around some and it had a bit of backfire through the carb (and a little out the tailpipe) but I _think_ that will be fixed by setting the timing.

Thanks for all of your help. I was getting really frustrated for a while there.

[danleaman]

Originally Posted by colbyclay

Sunday, we were able to get the truck started. We were able to do a rough, and I mean rough adjustment of the timing. We are going to get a timing gun soon to actually get it set correctly. We drove it around some and it had a bit of backfire through the carb (and a little out the tailpipe) but I _think_ that will be fixed by setting the timing.

Thanks for all of your help. I was getting really frustrated for a while there.

I don't intend to but into this, however. When you get the timing light also beg borrow or steal a dwell meter! Set the dwell first, then the timing as the dwell will effect timing. If you don't know how to adjust dwell, you are in luck! The GM distributor is the easiest to adjust, all it takes is a 1/8 allen wrench and a dwell meter. You can look up instructions that have photos at the library or on line. It's really easy, can be done with the engine running and is a much better adjustment than by feeler gauge.

Just my .02
Good luck

Dan

[colbyclay]

Originally Posted by danleaman

I don't intend to but into this, however. When you get the timing light also beg borrow or steal a dwell meter! Set the dwell first, then the timing as the dwell will effect timing. If you don't know how to adjust dwell, you are in luck! The GM distributor is the easiest to adjust, all it takes is a 1/8 allen wrench and a dwell meter. You can look up instructions that have photos at the library or on line. It's really easy, can be done with the engine running and is a much better adjustment than by feeler gauge.

Just my .02
Good luck

Dan

Dan (and anyone else reading this), you are NEVER butting in. I am on this forum because this is my first rebuild and I am a complete idiot when it comes to most part of rebuilding the truck! If wasn't for Google and searching this forum, I would be up the proverbial creek, having lost my paddle as soon as I started. With that said, we do have a dwell meeter. We tested the dwell and it was right on the money of 30, so there is that. To keep the engine running we had to set the idle very high. I adjusted the idle screw to max, then started to back it down some. It still is running too high IMO. I will start to adjust after we get the timing fixed.

Thanks!

[truckdude239]

idle will change when you set the timing if the idle is 2 high to start with it will be near impossible to time as the weights int he dis will be thrown outward advancing the timing.
dont ask me how i know this lol

[danleaman]

Originally Posted by truckdude239

idle will change when you set the timing if the idle is 2 high to start with it will be near impossible to time as the weights int he dis will be thrown outward advancing the timing.
dont ask me how i know this lol

So true, also since it's been sitting for a long time you may want to check all of the vacuum hoses for cracks or breaks and make sure they are connected to where they are supposed to go. Also make sure there are no open vacuum ports open a nasty vacuum leak can give you fits trying to get it to idle at the correct rpm. Hope you get it back on track.
Dan