GM Truck Club Forum banner

1 - 20 of 22 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter #1
Just bought a 92 1500 with a 4.3 and it has white smoke on start up. I have been searching around and have read that it could be a head gasket. Im ineed of some advise... I'm states away rigt now and only have 5 days to fix this before I have to take a 1,800 mile road trip. what should I do to fix this? Buy new heads or just gaskets? how likely is It to be a cracked head? thanks All
 

·
Registered
Joined
·
7,291 Posts
Welcome to the club. Could be valve guide seals.
 

·
Registered
Joined
·
541 Posts
Usualy you get white smoke because its burning coolant. It very well could be a head gasket and over the time its sitting its allowing coolant to leak into the cylinder and so when it starts up its burning off all the coolant. Does it seem like your coolant is low or you have to keep adding some? Start with checking your coolant level but as for replacing the head gasket(s) its hard to tell what one is bad so your probably better off just replacing both of them. I doubt that the heads are cracked. It could easly be a head gasket which I think the 4.3s are somewhat known to have ones that go bad and cause it to burn a little coolant. My 4.3 does but not really bad its not noticable and I only have to top it off every month or so.

Also does it smell like its burning oil? Like silverado said it could also be valve guide seals which arnt as hard as you think they are to replace. I would verify that its either oil or not. If it smells like its burining oil valve guide seals. If not probably coolant. But if you take your heads off you might as well put new valve guide seals in it anyways as there not very expencive and you can rent all the special tools you need at an autozone.

Good luck!
 

·
Registered
Joined
·
16 Posts
Discussion Starter #4 (Edited)
Well I thought It would be coolant aswell. Issue is Im miles away from it and a great road trip back to home when I get it. so If it is uncomon to have heard of crack heads on these 4.3s then I can count on head gaskets being the problem.


Next question is do 1992 heads have pressed or screw type rockers?
 

·
Registered
Joined
·
168 Posts
I would do a cylinder leakage test before I pull a head and make sure that is the problem and if so which head has a leaky gasket, I tend to agree with
silveradotrailblazer on the vlave guide or even more common ore valve stem seals. leaky cylinder heads tend to leak and continue to smoke even after startup, the exhaust should have a sweet smell if it is anti freeze.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #7
Ok Bigg Ron that sounds like a plan. If I have to remove the heads and replace them how long should it take? 4-6 hours is what Im thinking IDK
 

·
Registered
Joined
·
168 Posts
If you do the head gaskets, I would recommend having them checked for warppage at a machine shop, if the have any warppage they can resurface them, also would recommend new head bolts. But try the cylinder leak down test first, if you dont understand how to do this just ask. I dont think you can do it in 6 hours but you never know. I would like to see the chiltons time on that.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #9
Well I thought a 92 4.3 would be pretty simple/ not so complex. All I want Is to not to have worries or break down on the 1800+ trip back with the truck. if I did the heads what gasket would I be lookin to replace? intake, heads, throttle body? thats what I can put together in my mind
 

·
Registered
Joined
·
1,700 Posts
I wish you the best of luck, but buying an unknown 20 year old truck and taking a 1800 mile road trip 5 days later might not be wise. I would drive it as much as possible in the next few days and watch the oil and coolant closely. You might be able to do both heads in six hours if you are well setup.

You'll need head gaskets, intake & exhaust gaskets, and thermostat, dist, etc. You can get a head gasket set with everything you need and more.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #11
Dude thanks! Im setup with the regular tools that any car guy would have and I'm not afraid of hard work. my thought was if things are bad enough I.E. Blowing Smoke stacks or Loosing a lot of coolant) then get the head gasket kit and go at it. I fouond the heads remand for 300, so thats somewhat afordable. If it doesnt run funky or have a major loss of fluids then I will be ok
 

·
Registered
Joined
·
24 Posts
i used Bars Leak head gasket repair and it worked for me until i threw a rod. that was a couple years.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #13
I always had worries about bars cloggin up the radiator or heater core.... IDK guess it does work.
 

·
Registered
Joined
·
1,700 Posts
$300 for a pair of heads? That's pretty cheap. You could get out of the job for under $500 with gaskets, fluids, oil change, etc.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #15
Yeah I found them on ebay from a place about a 40 mins away from me in dallas. They are 340 shipped. If I have to I could get them. Although the more I think about it.the white smoke. Will likely have to do with the heads or their gaskets.
 

·
Registered
Joined
·
541 Posts
Its common for the "Vortec" heads to get warped head on them or blow headgaskets. Its very common for them to warp. Easy fix like others have said bring it to a machine shop and resurface them. Just take your time and do it right and it will work fine. Do your valve covers say Vortec on them?
 

·
Registered
Joined
·
16 Posts
Discussion Starter #17 (Edited)
Compression readings

Well here they are guys...
CYL 1=185 CYL 2=178
CYL 3=180 CYL 4=182
CYL 5=190 CYL 6=188
Forgot to ask my bro if the valve covers say vortec on them, but its a 92 thottle body injected ( carb with the 2 fuel injectors in it) so Id assume its not a vortec engine. with the numbers being this high Im thinking the engine was replaced or rebuilt not too many miles ago. Im leaning toward the valve seals being worn and if so would that cause the engine to burn alot of oil? How hard would it be to change the valve seals? Its to my understanding that I will need A spring compression tool, air compressor, and a fitting for the spark plug screw hole.
Now I wont get to the truck until the 22nd of this month so if you have any questions Id be askin my bro to check. What you folks think?
 

·
Registered
Joined
·
2,050 Posts
Leaking heads will often push oil in the the radiator (at least it did on a Ford I had). I would look for oily film in the top of the radiator. Also look for evidence of water in the oil. If you do not see evidence of oil where the water is suppose to be or water where the oil is suppose to be then I would focus on the valve guides unless the smoke continues while driving.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #19
My bro says it doesn't continue to smoke while driving... thank god!
I have my dad goin over to check a couple of things for me so I will ask him what's up.
 

·
Registered
Joined
·
1,700 Posts
Sounds like just some leaky valve seals. Nothing to worry about right now.
 
1 - 20 of 22 Posts
Top