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WRMZ71 · 12-10-2004, 01:41 PM

Has anybody ever had a headgasket go bad where the coolant slowly blows out with the exhaust? I'm thinking this is what is probably wrong with mine. There are no visual leaks anywhere running or not running but it slowly looses coolant. Can anybody give me a good idea for testing this? My only idea it to pull the plugs and then put a coolant system pressure tester on it and pump it up to see if coolant comes out of the spark plug holes. That and does anybody have a really clearcut symptom for a bad timing chain. Mine has been running like crud here lately and the carb i got is maybe a yr old and i always check it to see if its adjusted correctly. The wires, plugs, and distributor are maybe a yr to yr 1/2 old tops. What i get is sometimes its hard to start up like its flooding. When it finally starts it is really choppy and i'll hear almost small pops. I had a cam go flat one time and it almost sounded like some of these small pops. With a bad timing chain is your overall engine running quality very inconsistent? some times mine will run like sh!t and then the next day it will run like a champ. The reason I'm asking is because last time i took off the water it was like opening up pandora's box. You can read this http://www.67-72chevytrucks.com/vboa...591#post796591 and thats why i don't want to take off the water pump to get to the timing chain if i don't have to.

67ChevyRedneck · 12-10-2004, 02:20 PM

If it is blowing out of the exhaust there will be traces of white smoke and there will be excessive water dripping from the tailpipe....small amounts of condensation are normal at startup. If there are no visible leaks, it probably is a head gasket. What is also possible is your radiator is plugged and it is boiling over out of the spill container....be something to check also. To check if it is a radiator, you can check flow by waiting for it to warm up and once the thermostat opens, using a thick rag, squeeze the upper radiator hose. You should feel a stong rush of water through the hose. Also, check to see that your lower radiator hose has a spring in it. They can close off when hot and cause overflow. Just some ideas. A bad timing chain will make some sort of noise. I had the same problem with my truck. One day it will run great, next day like a POS Ford. IT would run good one day, then pop and spit and "diesel" on others. Turns out, when I changed the cap on the distributor I forgot to put the small metal ground strap back on that connects to the coil and the cap. It eventuelly killed my HEI and coil. Thats how I found out I forgot the strap. Without being grounded out the spark can randomly fire and arc inside the cap, causing irratic idle and popping. The truck was timed right....between 4-8 degrees BTDC. Also, check your actual timing. A 350 should be timed between 4-8 degrees before top dead center. 4 degrees is better for fuel miles/less power. I have mine at 8 degrees for some more ponies. I bought a timing light. Good investment. Just make sure engine is at operating temp when you check timing. Also, might need to check with someone else, but I THINK you MAY need to unhook the vacuum advance when you check it.....I can't find my engine book at the moment....but GOOD LUCK MAN! I hope i've helped you some.

mrein3 · 12-10-2004, 02:28 PM

The slow loss of coolant is probably just coolant going out the overflow tube. Unless you installed a recovery system your truck was designed to vent extra coolant on to the ground.

Your timing chain wouldn't cause an intermittent problem. At least I've never seen one do that. Assuming the parts you bought, wires, plugs, and distributor (cap?) are good look at other parts in the ignition systm. Coil. Points (dwell set right and points not burnt).

I have replaced points with a cheap set and couldn't get the engine to start again until I put the old set back in.

67ChevyRedneck · 12-10-2004, 02:43 PM

Good point mrein3, I don't have one on my truck either.....I have to add maybe a quart of water/antifreeze every month or so, no big deal. Also, what i said about the coil only applies to HEI ignitions...if you have points I can't help ya because I hate points and I immediately changed to later model HEI.

WRMZ71 · 12-10-2004, 05:11 PM

I do have HEI and i hate points too. As far as the cooling system goes, I have a little over 1 yr old brand new 4 core radiator, just put in a new thermostat for the winter, and i had also installed a coolant recovery tank. I can guarantee you that there are no leaks and the thermostat has been opening fine and the bottom line isn't collapsing. I was wondering if my idea with the coolant system pressure tester would be the best way to check for these leaks going into the combustion chamber. It doesn't really smoke and as far as moisture in the exhaust I've always seemed to have a little. I'm thinking its gotta be the darn timing chain cause everything else is too new.

WRMZ71 · 12-10-2004, 05:17 PM

Oh that and has anybody ever fiddled with the 670 holley street avenger carbuerator? It says in the owners manual that they are equipped with Morlain fuel filters or something like that. Can anybody confirm my thoughts about this filter more than likely being right where the fuel lines go into the carbuerator?

71-longbed · 12-10-2004, 05:23 PM

i've been told that some water out of the exhaust isn't a bad thing .....

dons454s · 12-10-2004, 05:53 PM

If it is burning the antifreeze you can pull the plugs and see they will be green tinted on the ends check it out

67ChevyRedneck · 12-10-2004, 06:14 PM

It's not a bad thing to have water in the exhaust. It's normal, but there should't be water constantly dripping. I'd check your distributor cap and look for scorch marks and "lighning" lines, and maybe even a crack??? Also, do check to make sure that the ground strap is inside the cap where the coil goes.....my truck was doing exactly what yours did. Also, had it always run this way??? or just since you've done the tune-up??? It is also possible that the timing chain is loose and has jumped time....it is possible to do this without it being noisy. Do the easy things first. Check the plugs/wires/cap/rotor first. Then purchase or borrow or get a garage to check your timing with a timing light. If it is off you can try adjusting the distributor, if it won't adjust and run right and is way off....your chain could have jumped time....it's so hard to determine anything without looking at it for myself....you got a whole weekend....good luck!!!!!

WRMZ71 · 12-10-2004, 07:09 PM

Nope just started doing it here lately. I've been checking the wires and the # 5 and 7 wires had some pretty good oil around them from a leaky dipstick so i took those off and wiped em and cleaned em up good and figured i'd fix that darn oil leak went to pull the dipstick tube and the bottom part broke off up in the block. (stupid cheap chrome crap) well i finally got that out and now i'm gonna reset the carb and see what i get then. dang shananigans anyway.

12-10-2004, 01:41 PM	#1
WRMZ71 Cause the Chicks DIG IT!! Join Date: Nov 2003 Location: Beaufort SC Posts: 509	Has anybody ever...... Has anybody ever had a headgasket go bad where the coolant slowly blows out with the exhaust? I'm thinking this is what is probably wrong with mine. There are no visual leaks anywhere running or not running but it slowly looses coolant. Can anybody give me a good idea for testing this? My only idea it to pull the plugs and then put a coolant system pressure tester on it and pump it up to see if coolant comes out of the spark plug holes. That and does anybody have a really clearcut symptom for a bad timing chain. Mine has been running like crud here lately and the carb i got is maybe a yr old and i always check it to see if its adjusted correctly. The wires, plugs, and distributor are maybe a yr to yr 1/2 old tops. What i get is sometimes its hard to start up like its flooding. When it finally starts it is really choppy and i'll hear almost small pops. I had a cam go flat one time and it almost sounded like some of these small pops. With a bad timing chain is your overall engine running quality very inconsistent? some times mine will run like sh!t and then the next day it will run like a champ. The reason I'm asking is because last time i took off the water it was like opening up pandora's box. You can read this http://www.67-72chevytrucks.com/vboa...591#post796591 and thats why i don't want to take off the water pump to get to the timing chain if i don't have to.

12-10-2004, 02:28 PM	#3
mrein3 Registered User Join Date: Feb 2000 Location: Center City, MN, USA Posts: 3,253	The slow loss of coolant is probably just coolant going out the overflow tube. Unless you installed a recovery system your truck was designed to vent extra coolant on to the ground. Your timing chain wouldn't cause an intermittent problem. At least I've never seen one do that. Assuming the parts you bought, wires, plugs, and distributor (cap?) are good look at other parts in the ignition systm. Coil. Points (dwell set right and points not burnt). I have replaced points with a cheap set and couldn't get the engine to start again until I put the old set back in. __________________ '70 cab, '71 chassis, 383, TH350, NP205. '71 Malibu convertible '72 Malibu hard top Center City, MN

12-10-2004, 05:23 PM	#7
71-longbed Its Magically Delicious Join Date: Jan 2003 Location: oregon Posts: 2,398	i've been told that some water out of the exhaust isn't a bad thing ..... __________________ 71 C10 LWB 350sbc -TH350 12 bolt 3.42 Posi Of all my favorite things to do, The utmost is to have a brew. My love grows for my foamy friend, with each thirst-quenching elbow bend. Beer so frosty, smooth, and cold it's paradise pure liquid gold. Yes beer means many things to me that's all for now cus I gotta pee.

12-10-2004, 02:20 PM	#2
67ChevyRedneck Hittin E-Z Street on Mud Tires Join Date: Nov 2004 Location: Greenville, SC Posts: 23,090	If it is blowing out of the exhaust there will be traces of white smoke and there will be excessive water dripping from the tailpipe....small amounts of condensation are normal at startup. If there are no visible leaks, it probably is a head gasket. What is also possible is your radiator is plugged and it is boiling over out of the spill container....be something to check also. To check if it is a radiator, you can check flow by waiting for it to warm up and once the thermostat opens, using a thick rag, squeeze the upper radiator hose. You should feel a stong rush of water through the hose. Also, check to see that your lower radiator hose has a spring in it. They can close off when hot and cause overflow. Just some ideas. A bad timing chain will make some sort of noise. I had the same problem with my truck. One day it will run great, next day like a POS Ford. IT would run good one day, then pop and spit and "diesel" on others. Turns out, when I changed the cap on the distributor I forgot to put the small metal ground strap back on that connects to the coil and the cap. It eventuelly killed my HEI and coil. Thats how I found out I forgot the strap. Without being grounded out the spark can randomly fire and arc inside the cap, causing irratic idle and popping. The truck was timed right....between 4-8 degrees BTDC. Also, check your actual timing. A 350 should be timed between 4-8 degrees before top dead center. 4 degrees is better for fuel miles/less power. I have mine at 8 degrees for some more ponies. I bought a timing light. Good investment. Just make sure engine is at operating temp when you check timing. Also, might need to check with someone else, but I THINK you MAY need to unhook the vacuum advance when you check it.....I can't find my engine book at the moment....but GOOD LUCK MAN! I hope i've helped you some.

12-10-2004, 02:43 PM	#4
67ChevyRedneck Hittin E-Z Street on Mud Tires Join Date: Nov 2004 Location: Greenville, SC Posts: 23,090	Good point mrein3, I don't have one on my truck either.....I have to add maybe a quart of water/antifreeze every month or so, no big deal. Also, what i said about the coil only applies to HEI ignitions...if you have points I can't help ya because I hate points and I immediately changed to later model HEI.

12-10-2004, 05:11 PM	#5
WRMZ71 Cause the Chicks DIG IT!! Join Date: Nov 2003 Location: Beaufort SC Posts: 509	I do have HEI and i hate points too. As far as the cooling system goes, I have a little over 1 yr old brand new 4 core radiator, just put in a new thermostat for the winter, and i had also installed a coolant recovery tank. I can guarantee you that there are no leaks and the thermostat has been opening fine and the bottom line isn't collapsing. I was wondering if my idea with the coolant system pressure tester would be the best way to check for these leaks going into the combustion chamber. It doesn't really smoke and as far as moisture in the exhaust I've always seemed to have a little. I'm thinking its gotta be the darn timing chain cause everything else is too new.

12-10-2004, 05:17 PM	#6
WRMZ71 Cause the Chicks DIG IT!! Join Date: Nov 2003 Location: Beaufort SC Posts: 509	Oh that and has anybody ever fiddled with the 670 holley street avenger carbuerator? It says in the owners manual that they are equipped with Morlain fuel filters or something like that. Can anybody confirm my thoughts about this filter more than likely being right where the fuel lines go into the carbuerator?

12-10-2004, 05:53 PM	#8
dons454s Registered User Join Date: Nov 2004 Location: Claysburg, Pa Posts: 408	If it is burning the antifreeze you can pull the plugs and see they will be green tinted on the ends check it out

12-10-2004, 06:14 PM	#9
67ChevyRedneck Hittin E-Z Street on Mud Tires Join Date: Nov 2004 Location: Greenville, SC Posts: 23,090	It's not a bad thing to have water in the exhaust. It's normal, but there should't be water constantly dripping. I'd check your distributor cap and look for scorch marks and "lighning" lines, and maybe even a crack??? Also, do check to make sure that the ground strap is inside the cap where the coil goes.....my truck was doing exactly what yours did. Also, had it always run this way??? or just since you've done the tune-up??? It is also possible that the timing chain is loose and has jumped time....it is possible to do this without it being noisy. Do the easy things first. Check the plugs/wires/cap/rotor first. Then purchase or borrow or get a garage to check your timing with a timing light. If it is off you can try adjusting the distributor, if it won't adjust and run right and is way off....your chain could have jumped time....it's so hard to determine anything without looking at it for myself....you got a whole weekend....good luck!!!!!

12-10-2004, 07:09 PM	#10
WRMZ71 Cause the Chicks DIG IT!! Join Date: Nov 2003 Location: Beaufort SC Posts: 509	Nope just started doing it here lately. I've been checking the wires and the # 5 and 7 wires had some pretty good oil around them from a leaky dipstick so i took those off and wiped em and cleaned em up good and figured i'd fix that darn oil leak went to pull the dipstick tube and the bottom part broke off up in the block. (stupid cheap chrome crap) well i finally got that out and now i'm gonna reset the carb and see what i get then. dang shananigans anyway.



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