5.7 using oil, no smoke

[Wozny]

The direct answer to your question is...no! It is all being burned up by the catalytic converter. This is what they do! If you want to see the smoking chimney effect just remove the cat.

OK, makes sense to me, it’s definitely not leaking or going out the pipe! Thanks, im just going to take out and to the rebuildrr’s. It looks like it’s time for it too, black crud all over Thanks

 

[Wozny]

The direct answer to your question is...no! It is all being burned up by the catalytic converter. This is what they do! If you want to see the smoking chimney effect just remove the cat.

Just realized, that smoke the catalytic converter is burning, where does all that carbon end up, does it come out the tailpipe in crumbs? If it didn’t, at a quart per 60 miles it seems like it wouldn’t take long to completely plug itself up.

 

[Wozny]

Nope. Dig in deep on how to do a leakdown test.
A compression test and a leakdown test are skills you should master if you are going to understand how engines work.
I can already guess that the engine is a crudded up sludge beast.
There are all kinds of old school tricks you can try to slap a little more life into that thing.
Dont sweat about the oil pressure to much at this point.
It is what it is.
A 350 will run on ridicously low oil pressure.
As long as it has enough to trigger the oil pressure sensor so the fuel pump runs.
Think of it as a learning opportunity.
Almost every old mechanic in this country started on a small block chevy.
Keep posting questions anytime and there is no dumb question
ask away bud

Thanks, I’ve been wanting to know how to do a leak down test for a while now. I don’t think in this case though that I want to get more miles out if it. I can use all the power I can get and better milesge too. So will just pull her out this winter. Might even rebuild it myself, I have all the tools like dial bore indicator, the works. Never done a 350 before, just Toyotas, so might be back about that! Thanks a lot

 

[Wozny]

What weight oil is in the engine?

Thanks, I’ve been running 10-40, yeah, should be 20-50 I know, but It’s still going to burn a lot, just less, seems to me

 

[Wozny]

Cats operate around 1800 degrees . That will reduce or eliminate oil smoke from exhaust. A quart every 60 miles, unless its going by exhaust guides, should be fouling spark plugs. If rings are gummed up from lack of maintenance, running it with clean oil may clean them up and improve ring seal. Or someone changed IC and its got half a million miles! LOL I would still pull valve covers and look

This is hard to believe but I changed that oil soon as I bought it, ran it 400 miles, changed it again and that oil with 400 miles was thick as hot tar and black as coal all over again. For a while I thought I forgot to change it the first time, then remembered I had for sure. So good idea, I’ll run it some more and see if the rings seal and let you know what happens. I don’t drive it much tho do might be a while

 

[thinger2]

This is hard to believe but I changed that oil soon as I bought it, ran it 400 miles, changed it again and that oil with 400 miles was thick as hot tar and black as coal all over again. For a while I thought I forgot to change it the first time, then remembered I had for sure. So good idea, I’ll run it some more and see if the rings seal and let you know what happens. I don’t drive it much tho do might be a while

Yep, shes a sludge monster. The old oil was black from dirt,crud,carbon etc suspended in the oil. It was to the point that nothing else could chemically bond to it so the rest ends up coating the inside of the engine as sludge. When you add new oil, all that crud starts bonding into the oil again untill it cant absorb anymore and the cycle repeats. It may take several oil changes before it improves.
Make sure your pcv system is working because it will tend to plug up pretty quick and that can spring all kinds of gasket leaks so keep an eye on it.
Its also quite likely that you have an oil filter bypass plugged full of crap. I would pull it out and clean it.
Its also a good idea to cut your oil filters open and see what is trapped in the pleats.
Once you get some semi clean oil running through it, cut the filter open and look for glitter
And, if youre gonna drive it for awhile before you pull the pin on a rebuild, take a look at running DELO diesal oil.
like a 15-40 during the summer it will be fine.
And take a look at every other fluid on that truck. If they didnt changa the oil, they sure as hell didnt change the trans or the diffs or anything else
Please post some pics when you take the valve covers and intake off.
I know some people who dont change their oil and I want to show them that its not a myth

 

[thinger2]

1. In a world where tool-shaped objects are sold by companies like Hazzard Fraught, "Low compression" can be an inaccurate gauge as easily as a problem with the engine. VERIFY the compression tester before condemning the engine.

2. "Oil in the cylinders" during a compression test never made sense to me; how is the oil supposed to climb the cylinder wall on the intake-manifold side to seal the rings on the "uphill" side of the cylinder? I quit adding oil to cylinders decades ago.

3. A leakdown test is excellent for finding low-power, non-sealing cylinders. A cylinder can seal and have compression but still burn oil. This is especially true if the oil is coming down the valve guide
or sucked-through the PCV. There's a pretty fair chance that neither of those issues will show up in a leakdown test.

4. Any chance this engine has aftermarket valve covers? Aftermarket covers often have crappy oil separators. Any oil in the PCV hoses?

"Hazzard Fraught" im gonna steal that.
Ill trade you for
"Hardley functional"
"Harbor Flotsam"
"Harbor Fart"
And my favorite,
How da **** tools.
It just kills me to watch guys trying to get input from garbage.
And, more and more We are becoming a tool desert.
Weve really backed ourselves into a chinese corner

 

[ThundahBeagle]

I mainly buy my tools used at Craigslist or local flea markets. Look for old Craftsman, 1946-1967, but even into the late 1990's is good. Or S-K tools, or Snap on or something like that.

Sorry to hear about this engine oil issue. I'm watching. Had an old 1994 big Blazer Silverado that was losing oil but not leaking or smoking. At the time I didnt have enough $ for proper car and just kept putting in more oil. It eventually just stopped running and I went with a Goodwrench crate motor.

 

[Schurkey]

"Hazzard Fraught" im gonna steal that.

You're not stealing it from me. I stole it from these guys:

https://itsamanslife.com/wp-content/uploads/2012/11/ToolSale.pdf

 

[mykytiuk]

Just realized, that smoke the catalytic converter is burning, where does all that carbon end up, does it come out the tailpipe in crumbs? If it didn’t, at a quart per 60 miles it seems like it wouldn’t take long to completely plug itself up.

Actually ... if anything comes out it will be ashes. A cat will get hot enough to do that when it needs to. If just idling around town it may not get that hot to burn everything up but at continued highway speed or, better yet, towing will get it glowing red if it’s loading up. I had a 454 that used about a quart to 100 miles and I musta drove it 30k like that. Yea...lots of cheap oil. Still had good power and would get 14 mpg on the highway at 70 to 80 mph so I’m pretty sure the cat never plugged.