Blown Head gasket or intake manifold? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

fostrem · 08-13-2012, 05:37 PM

First off my truck is a 76 k10 with a 350sbc in it. The reason I got to the conclusion that it was a head gasket was that it was smoking a ton. It would billow out the exhaust and the once the truck heated up, some smoke would come out of the left side of the engine. The truck barely runs as is. It can barely idle and eventually dies if i don't mess with the throttle even though the idle is set high. I set the initial timing to about 10 degrees but haven't been able to set total because the thing won't run long enough. I think its the head gasket. I checked the coolant over flow tank which was bone dry and when i drained the coolant, it still had a nice green look to it, not milky and no traces of oil. I then checked my oil which had a tinge of gas smell. Before I rip the heads off, do you think it is the head gaskets? intake manifold gasket? The only thing that worries me is the amount of smoke. The smoke is white ish and is not steam it smells like burning gas/oil.

Thanks in advance

fostrem · 08-13-2012, 06:16 PM

I just ripped the valve covers off and they are completely clean, normal build up but no milky/lotion sludge that would be signs of coolant oil mixing.

**old Rusty C10** · 08-13-2012, 06:21 PM

if the oil is full of gas id be looking at the fuel pump

fostrem · 08-13-2012, 06:31 PM

would that explain all the smoke though? especially the smoke coming out of the passengers side of the engine?

rwhit57 · 08-13-2012, 06:50 PM

Quote:

Originally Posted by fostrem

would that explain all the smoke though? especially the smoke coming out of the passengers side of the engine?

The fuel pump leaking gas into the crank could do this, it thins the oil so much it blows by everything. Certainly an inexpensive place to start.

fostrem · 08-13-2012, 07:18 PM

ok i will replace the fuel pump in a few hours. is there an easy way to tell if my intake manifold gasket is blown?

rwhit57 · 08-13-2012, 08:47 PM

Quote:

Originally Posted by fostrem

ok i will replace the fuel pump in a few hours. is there an easy way to tell if my intake manifold gasket is blown?

Be sure and change the oil and filter. An intake gasket will suck air or leak oil. One step at a time. Change the pump, oil and filter, might solve it.

**Corts60** · 08-13-2012, 09:03 PM

The first thing you need to be doing is a compression check. Don't tear into it without knowing the condition of the cylinders/combustion chambers/valves. Then you'll know what to look for. If your trying to do it cheap, you may have to only pull one head if there is a bad head gasket.

xrcr · 08-14-2012, 07:14 AM

are any of your plugs wet?

fostrem · 08-14-2012, 03:33 PM

no none of the plugs are wet

fostrem · 08-14-2012, 07:27 PM

ok so heres the update. I changed the fuel pump, oil, oil filter and fuel lines because they were cracked. right when i started it up it smoked like usual then it seemed to blow it off and the smoke was gone! no more smoke coming from the tail pipes and the engine sounds pretty good. needs some timing adjustment but thats easy enough. the only problem i have now is a good amount of smoke coming from the passenger side of the engine. i attached the picture of where the smoke was coming from. seemed to be from my exhaust. need new gasket? thanks for all the help so far

rwhit57 · 08-15-2012, 01:42 AM

Looks to me like the valve cover gasket leaking onto the exhaust manifold.

fostrem · 08-15-2012, 06:20 PM

ok now i am getting quite a bit of smoke out of the exhaust but only when accelerating. it is not water vapor but lingering smoke, kind of smells like burning oil. and also upon immediate start up, the oil pressure jumps to about 45 to 50 lbs. could these be symptoms of valve seals?

rwhit57 · 08-15-2012, 07:41 PM

Usually smoke on start up is the valve guides, and really not a big issue.What kind of oil did you put in? My first thought is it will probably straighten up and be ok, I would just drive it easy for a days and not be pushing it. I would have put some 10-40w or some straight 30w, oil in it.That oil press sounds fine. That gas in there probably knocked all kinds of stuff loose, I think I would run it a couple of hundred miles and change the oil again.

fostrem · 08-16-2012, 10:09 AM

Should I be worried about the smoking out the exhaust while driving?
Posted via Mobile Device

fostrem · 08-16-2012, 10:22 AM

Should I be worried about the smoke out the exhaust while driving it?
Posted via Mobile Device

rwhit57 · 08-16-2012, 11:46 AM

Well if it doesn't slow down or quit yes. You also might try an oil additive, maybe some of the guys could suggest something. Maybe Restore, or that stuff Sea foam. That gas in the oil could have caused permanent damage, but if it's not knocking or rattling it's worth a shot to try to work it out. A little thicker oil an additive or two and drive it easy and see what happens.

fostrem · 08-16-2012, 08:16 PM

well after a compression test, the passengers side cylinders all read 147-150. the drivers side how ever, cylinders 1 and 3 have no compression and 5 and 7 have very low (around 60). Is this the head gasket?

rwhit57 · 08-17-2012, 03:12 AM

Well that sucks. It could be a head gasket since it's isolated to one side. Sounds like it's time to tear into that side and start inspecting things. Did it run ok before?

fostrem · 08-17-2012, 04:40 AM

it hasn't run well for a few months, ever since i had some valve work done. I'm thinking there could be bent valves on cyl1 and 3. I'm tearing that side down tomorrow ill let y'all know what the problem is

rwhit57 · 08-17-2012, 06:15 PM

[QUOTE=fostrem;5543283]it hasn't run well for a few months, ever since i had some valve work done. /QUOTE]

This is where we should have started out.

88Jimmy4x4 · 08-17-2012, 08:49 PM

Quote:

Originally Posted by fostrem

it hasn't run well for a few months, ever since i had some valve work done. I'm thinking there could be bent valves on cyl1 and 3. I'm tearing that side down tomorrow ill let y'all know what the problem is

sounds just like my 76, mine was a cracked head

Dead Parrot · 08-18-2012, 10:56 PM

Before pulling the head, try backing off the rocker arm nuts about a half turn or so. If the mechanic over tightened them, it could cause the low compression.

Project77 · 08-18-2012, 11:23 PM

just had a 94 truck in the shop i work at it had blow by(white smoke) coming out of the oil fill cap the truck wouldnt idle had to keep throttling it. eventually we did a compression test and one cylinder had low compression while all the others were around in the same range. the conclusion was bad rings on the one piston which was allowing gas to get into the oil. sound like your problem? compression test is very important make sure all of the cylinders are in close range to eachother

McMurray76 · 08-17-2012, 03:48 PM

I think I'd be talking to the guy that did the valve work.

08-13-2012, 05:37 PM	#1
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Blown Head gasket or intake manifold? First off my truck is a 76 k10 with a 350sbc in it. The reason I got to the conclusion that it was a head gasket was that it was smoking a ton. It would billow out the exhaust and the once the truck heated up, some smoke would come out of the left side of the engine. The truck barely runs as is. It can barely idle and eventually dies if i don't mess with the throttle even though the idle is set high. I set the initial timing to about 10 degrees but haven't been able to set total because the thing won't run long enough. I think its the head gasket. I checked the coolant over flow tank which was bone dry and when i drained the coolant, it still had a nice green look to it, not milky and no traces of oil. I then checked my oil which had a tinge of gas smell. Before I rip the heads off, do you think it is the head gaskets? intake manifold gasket? The only thing that worries me is the amount of smoke. The smoke is white ish and is not steam it smells like burning gas/oil. Thanks in advance

08-13-2012, 06:16 PM	#2
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? I just ripped the valve covers off and they are completely clean, normal build up but no milky/lotion sludge that would be signs of coolant oil mixing.

08-13-2012, 06:21 PM	#3
old Rusty C10 Robert Olson Transport Join Date: Oct 2002 Location: recent transplant to NC USA Posts: 20,310	Re: Blown Head gasket or intake manifold? if the oil is full of gas id be looking at the fuel pump __________________ Bob 1951 International running on a squarebody chassis "If a man's worth is judged by the people he associates himself with, then i am the richest man in the world knowing some of the fine people of this board" http://67-72chevytrucks.com/vboard/a...t.php?f=25&a=9 (you can review the site rules here!) PM Me for your vehicle/parts hauling needs in the North East US or see my Facebook page Robert Olson Transport Live each day to the fullest.. you never know when fate is going to pull the rug out from under you... I hate cancer!!

08-13-2012, 06:31 PM	#4
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? would that explain all the smoke though? especially the smoke coming out of the passengers side of the engine?

08-13-2012, 07:18 PM	#6
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? ok i will replace the fuel pump in a few hours. is there an easy way to tell if my intake manifold gasket is blown?

08-13-2012, 09:03 PM	#8
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,697	Re: Blown Head gasket or intake manifold? The first thing you need to be doing is a compression check. Don't tear into it without knowing the condition of the cylinders/combustion chambers/valves. Then you'll know what to look for. If your trying to do it cheap, you may have to only pull one head if there is a bad head gasket. __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/showthread.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 73 Chevy C20(Daily)http://67-72chevytrucks.com/vboard/s...d.php?t=852767 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(sold)

08-14-2012, 07:14 AM	#9
xrcr Registered User Join Date: Dec 2008 Location: Foristell, MO Posts: 418	Re: Blown Head gasket or intake manifold? are any of your plugs wet?

08-14-2012, 03:33 PM	#10
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? no none of the plugs are wet

08-14-2012, 07:27 PM	#11
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? ok so heres the update. I changed the fuel pump, oil, oil filter and fuel lines because they were cracked. right when i started it up it smoked like usual then it seemed to blow it off and the smoke was gone! no more smoke coming from the tail pipes and the engine sounds pretty good. needs some timing adjustment but thats easy enough. the only problem i have now is a good amount of smoke coming from the passenger side of the engine. i attached the picture of where the smoke was coming from. seemed to be from my exhaust. need new gasket? thanks for all the help so far Attached Images

08-15-2012, 01:42 AM	#12
rwhit57 Registered User Join Date: Jan 2011 Location: Tulsa,Okla Posts: 590	Re: Blown Head gasket or intake manifold? Looks to me like the valve cover gasket leaking onto the exhaust manifold. __________________ "Whoever said money can't buy happiness has obviously never seen a speed shop!

08-15-2012, 06:20 PM	#13
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? ok now i am getting quite a bit of smoke out of the exhaust but only when accelerating. it is not water vapor but lingering smoke, kind of smells like burning oil. and also upon immediate start up, the oil pressure jumps to about 45 to 50 lbs. could these be symptoms of valve seals?

08-15-2012, 07:41 PM	#14
rwhit57 Registered User Join Date: Jan 2011 Location: Tulsa,Okla Posts: 590	Re: Blown Head gasket or intake manifold? Usually smoke on start up is the valve guides, and really not a big issue.What kind of oil did you put in? My first thought is it will probably straighten up and be ok, I would just drive it easy for a days and not be pushing it. I would have put some 10-40w or some straight 30w, oil in it.That oil press sounds fine. That gas in there probably knocked all kinds of stuff loose, I think I would run it a couple of hundred miles and change the oil again. __________________ "Whoever said money can't buy happiness has obviously never seen a speed shop!

08-16-2012, 10:09 AM	#15
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? Should I be worried about the smoking out the exhaust while driving? Posted via Mobile Device

08-16-2012, 10:22 AM	#16
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? Should I be worried about the smoke out the exhaust while driving it? Posted via Mobile Device

08-16-2012, 11:46 AM	#17
rwhit57 Registered User Join Date: Jan 2011 Location: Tulsa,Okla Posts: 590	Re: Blown Head gasket or intake manifold? Well if it doesn't slow down or quit yes. You also might try an oil additive, maybe some of the guys could suggest something. Maybe Restore, or that stuff Sea foam. That gas in the oil could have caused permanent damage, but if it's not knocking or rattling it's worth a shot to try to work it out. A little thicker oil an additive or two and drive it easy and see what happens. __________________ "Whoever said money can't buy happiness has obviously never seen a speed shop!



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08-16-2012, 08:16 PM	#18
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? well after a compression test, the passengers side cylinders all read 147-150. the drivers side how ever, cylinders 1 and 3 have no compression and 5 and 7 have very low (around 60). Is this the head gasket?

08-17-2012, 03:12 AM	#19
rwhit57 Registered User Join Date: Jan 2011 Location: Tulsa,Okla Posts: 590	Re: Blown Head gasket or intake manifold? Well that sucks. It could be a head gasket since it's isolated to one side. Sounds like it's time to tear into that side and start inspecting things. Did it run ok before? __________________ "Whoever said money can't buy happiness has obviously never seen a speed shop!

08-17-2012, 04:40 AM	#20
fostrem Registered User Join Date: Jun 2012 Location: Seattle, WA Posts: 44	Re: Blown Head gasket or intake manifold? it hasn't run well for a few months, ever since i had some valve work done. I'm thinking there could be bent valves on cyl1 and 3. I'm tearing that side down tomorrow ill let y'all know what the problem is

08-17-2012, 06:15 PM	#21
rwhit57 Registered User Join Date: Jan 2011 Location: Tulsa,Okla Posts: 590	Re: Blown Head gasket or intake manifold? [QUOTE=fostrem;5543283]it hasn't run well for a few months, ever since i had some valve work done. /QUOTE] This is where we should have started out. __________________ "Whoever said money can't buy happiness has obviously never seen a speed shop!

08-18-2012, 10:56 PM	#23
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,611	Re: Blown Head gasket or intake manifold? Before pulling the head, try backing off the rocker arm nuts about a half turn or so. If the mechanic over tightened them, it could cause the low compression.

08-18-2012, 11:23 PM	#24
Project77 Registered User Join Date: Dec 2010 Location: Hallettsville, Texas Posts: 363	Re: Blown Head gasket or intake manifold? just had a 94 truck in the shop i work at it had blow by(white smoke) coming out of the oil fill cap the truck wouldnt idle had to keep throttling it. eventually we did a compression test and one cylinder had low compression while all the others were around in the same range. the conclusion was bad rings on the one piston which was allowing gas to get into the oil. sound like your problem? compression test is very important make sure all of the cylinders are in close range to eachother

08-17-2012, 03:48 PM	#25
McMurray76 Registered User Join Date: Dec 2009 Location: Columbus ohio Posts: 109	Re: Blown Head gasket or intake manifold? I think I'd be talking to the guy that did the valve work.

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