BRife
Registered Member
I just feel that the time and effort to pull the heads and have them redone, would be more then just finding a used good engine for 200-300 dollars because I herd having the heads done can be pretty expensive.
CK5
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Engine smoke 350 help
- Thread starter BRife
- Start date
You will have no idea on how well an engine runs unless you can hear it run first and even then someone could have done something to a bad engine to make it run "good" for a short period of time (enough to sell it to a sucker). You would be money ahead to tear into your engine first to see if you can find the problem (this cost you nothing but time) and if you find the problem then repair it otherwise go buy a used running engine and pray that it doesn't give up on you in 10 minutes, 10 days, 10 weeks, or maybe it will last you another 10 years.
Oh well, what would I know about this anyways since i've only built several thousand engines in my 22 years as an automotive machinist.
BRife
Registered Member
That makes sense of course, I guess my biggest thing is I would do a compression test on a motor before I did anything. But your right, exactly what happened with this engine, I bought this truck 4 months ago and the thing sounded great, but now having these problems.
Yes, repairing your current problem rather than buying ANOTHER potential problem would be alot better, also you'll know what has been done when you're finished.
BRife
Registered Member
Good advice thank you, I will have to assess my funds and take it from there.
My 2 cents is I wont put a nickel into an engine needing a valve job unless I do the rings also,because nearly every one I just put rebuilt heads on smoked like a chimmney afterwards...sealing up leaky valves will make the rings blow by and cause an engine that never smoked to start soing so ,almost certainly...I would say its worth doing a complete re-ring and valve job rather than trying to fudge it by doing a valve job alone.................................................................................................I feel a good running used engine is a bargain,provided you can hear it tun,and if you can drive the vehicle its in,thats even better...I've bought rotted out junk trucks just for the good running engines and trannys,that way I was able to test them out first before parting them out...salvage yards usually just listen to an engine run and maybe do a oil pressure and compression test(if that!), before they yank it and stick it on a shelf,so your pretty much relying on their honesty as to its actual condition.........................................................................................................I have also seen perfect running engines get stored and sit for way too long at these places that are junk by the time they get installed too,I have had such engines I stored away "improperly" that smoked and knocked after sitting several years...so just because it may have "only 50K on it",thats not always a certainty that it'll be good by the time its put back in something...most salvage yards will only give you another engine,no money for your labor or parts you put on the first "bad" engine too....usually you can buy a good running engine in a crappy rotbox for 500 bucks or so,then yank it out and scrap the leftovers,and get most if not all your cash back...
BRife
Registered Member
Okay, yes I know my engine requires a complete rebuild or nothing at all. I have found a few engines on craigslist that are still in the trucks and the guy seems very honest but I still have to go check them out.
454Sub
5/8 ton status
Or buy a junkyard motor, and do a cheapie rebuild to it, rings, bearings, gaskets, and redo the heads, all while driving the truck with the existing motor in it still. Me and a buddy are in the process of that with his 76 chevy, cept he bought a newer Vortec for some added power. Now we are just building the motor as he sees fit on his time, as his old 350 runs, just smokes and burns every fluid it has in it, but it does still motivate the truck enough to not pull it out yet.
BRife
Registered Member
Yeah haha thats what I am doing right now, driving it, smokes like hell, get lots of bad looks but it will still get me where I need to go untill I can find something to replace it. The truck is worth doing something with the motor so I will figure something out.
72 Blaze
1/2 ton status
I'm in the same boat! Bought a 79 K1500 about 6 months ago. Drove it 40 mins home after I test drove it... Twice ran great and still does. It blows blue smoke as it heats up and gets worse as I sit in traffic.
79rustyk10
3/4 ton status
Id look into rebuilding what you have. I've had bad luck with junkyard engines. the last one I bought was supposedly "low mileage" but had 1/8"+ of copper in the pan. bearings were wasted.
Like previously said, if you fix whats in the truck, then you know what you have when you're done.
SBC stuff is pretty inexpensive anyway.
Like previously said, if you fix whats in the truck, then you know what you have when you're done.
SBC stuff is pretty inexpensive anyway.
72 Blaze
1/2 ton status
Sorry didn't mean to hit send yet! Damn smart phone! Anyway took it to the shop. Valve seals were brand new and double lapped. I'm guessing it needs rings, but the guy working on it said to just drive it until it blows! I'm using about a quart every 4th fill up. The trucks runs great.... It just smokes, bad part is it only has 57k original miles on it. I guess sitting most of its life hurt it. It just sucks because I want to spend money on a lift kit and 35's but I need to save my money for a rebuild! I feel your pain man!
And it has new valve seals? Thats a little strange. More smoke sitting at a light is almost always valve seals.
I'd change the oil, go to a 20W50, and see what happens. Also double check to see if the oil smells like gas.
Also, if the oil does not smell like gas, consider a synthetic. Costs more, but does not tend to thin out when hot as much, and worth it for one change.
If it doesn't help, and you are using that much, then its not worth the money.
BRife
Registered Member
Well dang, thanks for your advice. I am glad I didnt do the valve seals because I do feel that would of been a waste, I dont believe it could be that. When I took the plugs out, the plug in the piston that has no compression, that the metal was pushed all the way into the electrode. You know what I mean the gap was closed. I am thinking that maybe a piece of the ring broke off and hit the end of the plug?
But I have not investigated it further.
But I have not investigated it further.
You said earlier that you didn't have a miss. With no gap in a plug. You for sure had a miss. Now, for the good news, you already found your problem. Just verify it. Pull your head and inspect. Broken piston, broken rings, broken valve, bent valve, the only way to verify is pull your head. The "piston rings" only come out the top of the block. Since you're certain you broke a ring, just replace the rings in that hole. Gaskets and a weekend will have you fixed in no time.
Now for the bad news. When you pull your head to get the piston out. Inspect the exhaust valve in that hole. It is probably bent or damaged also.
BRife
Registered Member
I didnt think I had a miss I was sure of it, because the thing ran so great and never skipped a beat, but sense the piston had no compression I dont think it was ever making any difference if it was missing or not, I pulled the plug wire after putting a new plug in and it ran the same so that shows that there is forsure a problem in that piston.
British Slave
1/2 ton status
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I would do a second compression check. if it runs as good as you say, I would think you didn't get a good check.
BRife
Registered Member
Trust me I did two checks on every piston, 75-80 in 6 of em, 65 in 1 and 0 in the other. Like someone said earlier, I think the entire engine is just weak, unless thats just the way the cam is set up I am not sure, but its starts on a dime, plenty of power under the pedal cruses at 60 mph just smokes like hell doing it.
If your a lucky guy maybe you'll find something like a broken rocker arm or a stud for one, that pulled out of the head or broke--its not too hard to pull the valve cover and inspect for that,and see if all the rockers move up and down the same amount while cranking it over,to see if a cam lobe was worn......................................................................................................--I've seen engines still run fairly quiet with those problems and it'll effectively "kill" that cylinder if its the intake valve not opening,it'll not let any air in TO compress and the result is no compression or power from that cylinder...sometimes the unburned fuel and oil from that cylinder will make smoke as it gets burned off in the exhaust.......other things that can cause smoking is a non operating PCV valve ,or aftermarket valve covers that aren't vented ,and a loose timing chain can throw the valve timing off and make an engine start using oil....
Good point Diesel4me.
If the intake valve won't open. No air to compress.
If the intake valve won't open. No air to compress.
