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Mike Chavez 07-16-2013 11:12 AM

Engine running rough
 
hi all,
I am new to the site, but I am really excited to be here..
Just purchased a 72 C10 that had been parked for five years. with just a few adjustments she fired up! I took it on a little test drive and was surprised how well she ran for a couple of days. that is when the problems began.
alternator grounded out, so I replaced that and now the motor is really running rough. planning on checking the fuel line next, but could use some suggestions.

Also, I noticed moisture coming out between the head and the intake manifold..what could cause this? bad valves, or gasket or ????

I am doing this on limited funds, and time so any help is appreciated.

SuperC10Tex 07-16-2013 11:58 AM

Re: Engine running rough
 
Welcome from Texas, you may wants to pull the plugs and clean them, if it has been parked for the last five years....you might need to pull and flush the gas tank. I am sure you will get other suggestions!!

sKnNyPpY 07-16-2013 12:44 PM

Re: Engine running rough
 
Check your grounds aren't broken or at least clean them up. Get the auto parts store to trickle charge your battery so it's nice and fully charged. Check your vacuum hoses for cracks. All that is basically free. Fuel and air filters, oil change and plugs are cheap. I also just got a $25 vacuum gauge that can help diagnose several engine problems and it came with instructions. After that HEI and if you haven't installed the alternator yet get one that is internally regulated not externally. The local parts place switched mine out when I still couldn't get the new externally regulated one and regulator to charge. HAVE FUN!

Also check your fusible link and wiring from the battery to the connector on the passenger side fender wall and wires going to the starter and the cab. I had problems there after grounding out my alternator. Cheap fix $4 for fusible link and little more for new wires if they're burned up.

68gmsee 07-16-2013 12:58 PM

Re: Engine running rough
 
Welcome to the site. Can you post more info on the truck like engine, carb, HEI or points, automatic or manual?

There's a lot of things that can make the engine run rough so check items mentioned above and I would recommend making a list of what needs to be done then check them off as you do them. Do the cheapest easiest first.

The leaking between the head and intake is probably a gasket problem. If it's bad, I would take care of that first as it may be getting into the cylinders. May also solve the running rough?

List of things to check and/or replace (some already mentioned).

Fuel contamination (filters, water in gas, old gas, etc.)
Vacuum leaks from old rubber hoses and gaskets
Timing
Ignition components (dist. cap, rotor, points, wires, plugs)
Vacuum advance not working
Debris in the carb

There are others but this gives you an idea.

Mike Chavez 07-16-2013 11:59 PM

Re: Engine running rough
 
thanks all for the suggestions. I did the plugs, re stabbed the distributor as it was off, changed the plug wires and it is already running better....looking at jetting up the carburetor next.
for those that asked for more info, it is a 350 small block, automatic, HEI, and has a quad jet standard carb.

cdowns 07-17-2013 05:20 AM

Re: Engine running rough
 
truck has been running for over 40 years so i'd think the carb jets are fine


clean and or replace the fuel filter in the carb inlet is time better spent


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