73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: screamin86 on April 21, 2010, 04:22:47 pm
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Well I've thought of every possibility and tried a few things and I'm stll getting smoke and can't pinpoint what it is! After I replaced the dizzy with one with new cap coil rotor and light weight springs it almost quit smoking completely. When I added a new fuel pump because the old one was leaking back it holds fuel better after turned off but now it smokes worse! Its not black smoke its almost white/blueish gray but smells like fuel! I'm stumped! :/ plugs don't look bad either! I'm gona reshoot timming and check fuel pressure again. Wost case scenario ima pull the heads and go through them. If I pull the pcv valve it doesn't some so not really any blow by. I've got 600miles on it all and its driving me insane!
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What trans do you have? If it's a THM350 or THM400 pull the vacuum hose off of the modulator and check for ATF
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Its a summit racing th350.
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OK check the modulator. Remove the hose and plug it. See if ATF drips out of the trans and see if the smoking stops
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Ill try that before I leave work tonight.
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well after scratching my head for the past month or so on my truck smoking its progressivly gotten worse ive added a fuel pressure regulator and t helped the fuel smell but im still getting smoke so i went and ordered a new set of headgaskets from advanced today and i plan to pull the heads off tomarrow and change them out and install my performer rpm intake. i was gona wait another week but the wife told me she volunteered me to move one of her friends next weekend so im gona bite the bullet and do it all this weekend. here is a video of whats going on. dont mind the wondering needle on my fuel psi gauge thats what i get for not buying a liquid filled one.
http://www.youtube.com/watch?v=Osk5Cbwozm8
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You've eliminated bad rings and/or leaky valve seals as a possibility? It doesn't look like a head gasket issue to me.
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I'm not getting any blow by from the valve cover breather or when I pull the pcv valve out not finding any oil deposits on my plugs other than a lil soot from when I was running almost 7lbs of fuel pressure.
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Is it using coolant?
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I've noticed a slight drop in the coolant level in my overflow tank over the past month. But no water in the oil or oil in the water.
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So why do you think you have bad headgaskets?
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I merged your posts because you really should continue from the original post.
Did you ever check the modulator?
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Sorry about that I had forgot about this post. Well like I said I am noticing a small loss of coolant but no mixing and I am going to change the intake and figure if I'm that far along ill do the heads to be safe. Every now and then I can smell antifreeze if the truck has been sitting for a few days.
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Doesn't sound like head gaskets at all to me. If you have ruled out the trans modulator...have you verified that it's not running extremely rich? Other than that I would wonder about a cracked ring or piston.
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I think that I'm going to check out the valve seals before I pull the heads. I've got a set of valve springs to put on anyway. It never smoked in the first 100miles until it got hot on me then since I've had the issues. It runs great and doesn't miss a beat it just smokes at idle and doesn't seem to "load up" at all.
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Alright I went out today and drove it a little and double checked my fuel presure and the modulator valve and found no issues. I did notice however that the radiator cap was fairly cool to the touch even with the temp gauge reading 190-200 I do owever have a efan that is running full time which may explain that.I do not see any smoke while driving but as soon as I stop it shws up bad. I will say a bad part on me when I put it together I used my 601 heads with about 83k on and all I did was check with straight edge and clean. It could be possible the valve seals are shot since it sat so much of its life.
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That video sure looks like a valve seal issue to me.
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I bought some valve seals and borrowing the tools to do it from a friend at work hopefully gona fix the issue this week
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valve seals generally smoke more with a cold engine. also, have you checked compression?
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well i worked on the truck some today to get some things done finaly and first i rented a coolant presure tester and found that there is a leak but its a slow leak so im with most of you now and dont believe its a headgasket. it took it a little over 2mins to go from 15-16lb to 9-11lbs. however when i got under the truck to drain the oil so i could drop the pan i found a couple of drops of colant hanging off the flexplate so idk whats going on there. i pulled the pan to investigate my wondering oil psi in uper rpm and the pickup had fallen off so instead of re soldering it i just installed a brand new summit racing kicked out 7qt pan i had in storage for a couple years and a new pump with bolted on/welded pickup. i bought a set of oil seals but then a friend of mine that helped me with my first motor build some years ago called and said he still had all my oil seals that came in a kit i bought but didnt need since the shop that did my machine work did my heads so im going to take back the ones i bought and use those and im gona install my valve springs that are good to .520 lift this week also since im still running the stock ones. the only thing still concerning me is the drops of coolant im finding could it be a leaky freeze plug or maybe the back of the intake leaking? anyway here is a video just showing the presure drop its a pretty boring video but i figured id make it for refrence.
http://www.youtube.com/watch?v=yLlvBCYzt6c