Engine using excessive oil "opinions wanted"

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Mofarmer

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Thanks for all the ideas, I currently have the MM in the oil I'll give it a chance to work if it doesnt I'll try some of the other suggestions. Thanks again
 

John Nes

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Had a customer come back to the shop a few weeks after he got an oil change on his 78 C-30 (502 big block) saying he was super low on oil, no leaks to be found, but he didn’t mention any smoking.... was kind of stumped about it until I looked at his aftermarket valve covers. Didn’t have a breather, therefore explained why he was losing that much oil. Not sure if your crankcase is ventilated or not, hopefully it is, but that’s def the easiest thing to check/fix first.

my 87 however has a little blowby from worn rings on the original 5.7 w/ 220k miles, been adding a bottle of Engine Restore with each oil change and hadn’t noticed as much smoke, but with nearly a quarter million miles, I’m not too worried about it lol
 

Rusty Nail

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A cheap one is with the engine running trickle a garden hose down the throttle keep it running with the throttle the water turns to steam in the combustion chamber and cleans up the top end. You will need new plugs afterwards. Justice Brothers came up with a similiar treatment we used at a couple of shops I worked at pull a vacuum hose connect manifold vacuum to a small tank with a valve attached put a stick on the throttle about 1500 rpm open the valve and let the mystery cleaner get sucked into the running cylinders. I think the cleaner was mostly acetone. Either way it's the most direct way of cleaning the combustion chamber and rings without a tear down. I still have a J.B. tank and valve if you want to borrow it.


Yeah dude. Stick a freakin garden hose down the carb while it's running especially - that oughta take care of that pesky 305. :rolleyes: but at least take a video or somethin!
 

SirRobyn0

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Yeah dude. Stick a freakin garden hose down the carb while it's running especially - that oughta take care of that pesky 305. :rolleyes: but at least take a video or somethin!

Thanks Rusty, I needed a good laugh.

In all honesty I thought the something when I saw Ricko's post. I've done water out of a bottle down the carb, out of a cup, out of a mug, poured slowly in listening carefully to the engine, but I would never advise someone that hasn't done a decarb with water to use a garden hose. Heck I wouldn't use a garden hose. There is just to much risk of to much water and engine damage IMO. And we should warn the OP that to much water at once down the carb can cause engine damage. I just want to be sure folks know to be careful with this method. But I do agree water is very effective when done carefully for decarb. Not sure about a possible sticky ring scenario.
 
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Ricko1966

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You first Ricko. :p
Done it lots of times. Ever look at the combustion chamber of a car with a leaking head gasket the offending cylinder and piston are spotless.As I said you just dribble water down the throat, or you can suck it in through a vacuum hose just like justice brothers decarb does.
 

Octane

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Done it lots of times. Ever look at the combustion chamber of a car with a leaking head gasket the offending cylinder and piston are spotless.As I said you just dribble water down the throat, or you can suck it in through a vacuum hose just like justice brothers decarb does.
It works,but I always preferred trans. fluid down the carb.
 

Matt69olds

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Kinda off the subject, but pretty good endorsement for the GM top engine cleaner product.

Many years ago when I worked at a Buick/Cadillac dealership, one of the old timers got a work order for a Cadillac Fleetwood with a engine knock. To me, it definitely sounded like bottom end noise. The guy didn’t think so, said to him it sounded like the noise was much higher up than crank or piston pin.

He did the water down the throttle body trick, followed by running 2 cans of top engine cleaner thru it, the noise disappeared. There were 2 huge piles of dark dusty crud (carbon) under each tailpipe. The car was owned by a very elderly couple, they rarely drive it, abd when they did, it probably never went faster than 40 mph. I would have never guessed that much carbon could collect on top of the pistons and still run, and would never have guessed enough carbon could build up that the piston could actually touch the head.
 

AuroraGirl

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Personally, before adding anything to the engine oil, I’d take it for a long drive. Give it a few full throttle acceleration pulls, work the engine hard. If the rings are sticky, some hard work and heat will clean things out.

Run a compression and leak down test. This will give you a good idea as to how well the engine is sealed up, in addition it gives you a perfect opportunity to check the condition of the plugs.

Does it smoke after sitting overnight? If so, classic symptom of valve seals. Those are fairly easy to change without engine or head removal.


If it doesn’t fog for mosquitoes going down the road, doesn’t leak, the plugs look good, and is otherwise an ok engine, I’d run some 10w40 or 15w40 Rotella and drive it until your ready for the engine swap. Maybe the thicker oil will slow down the consumption?
Any real chem in a bottle that CAN do anything usually requires it to be coating the intake valve and the piston for a long time like overnight then instruct to start engine after that and give her some gas but it would be pissing in the wind to attempt to fix a already gone carbon situation with a bottle
 

AuroraGirl

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Kinda off the subject, but pretty good endorsement for the GM top engine cleaner product.

Many years ago when I worked at a Buick/Cadillac dealership, one of the old timers got a work order for a Cadillac Fleetwood with a engine knock. To me, it definitely sounded like bottom end noise. The guy didn’t think so, said to him it sounded like the noise was much higher up than crank or piston pin.

He did the water down the throttle body trick, followed by running 2 cans of top engine cleaner thru it, the noise disappeared. There were 2 huge piles of dark dusty crud (carbon) under each tailpipe. The car was owned by a very elderly couple, they rarely drive it, abd when they did, it probably never went faster than 40 mph. I would have never guessed that much carbon could collect on top of the pistons and still run, and would never have guessed enough carbon could build up that the piston could actually touch the head.
The way geezers drive doesn’t take long to carbon even a modern car with dual direct and mpfi systems... they drive it under the factory design intention, which actually if you were to read the owners manual and follow would be OK for keeping cleared

the way they drive.. I put my gmas jeep in sport and went up a steep on ramp and did a fair sized cloud of grey smoke and I only last did it 7 months ago ?
Doesn’t take long
 

SirRobyn0

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Kinda off the subject, but pretty good endorsement for the GM top engine cleaner product.

Many years ago when I worked at a Buick/Cadillac dealership, one of the old timers got a work order for a Cadillac Fleetwood with a engine knock. To me, it definitely sounded like bottom end noise. The guy didn’t think so, said to him it sounded like the noise was much higher up than crank or piston pin.

He did the water down the throttle body trick, followed by running 2 cans of top engine cleaner thru it, the noise disappeared. There were 2 huge piles of dark dusty crud (carbon) under each tailpipe. The car was owned by a very elderly couple, they rarely drive it, abd when they did, it probably never went faster than 40 mph. I would have never guessed that much carbon could collect on top of the pistons and still run, and would never have guessed enough carbon could build up that the piston could actually touch the head.

Any real chem in a bottle that CAN do anything usually requires it to be coating the intake valve and the piston for a long time like overnight then instruct to start engine after that and give her some gas but it would be pissing in the wind to attempt to fix a already gone carbon situation with a bottle

We are getting a little side tracked here considering the OP has an oil control issue not a carbon issue, but I'm enjoying the discussion.

I've heard good things about GM top engine cleaner, but have no personal experience. I remember back in the 90's having a 1980's something Ford in the shop. Had a pretty bad carbon issue, one of the guys had run a couple of bottles of whatever cleaner we were using at the time, through what we called an IV drip system into the PCV line. Still had issues. So I sat out in the parking lot and SLOWLY ran a gallon of water through the intake right down the carb. That did the trick. Like in @Matt69olds story there was a big grayish black streak of crap on the ground that came out of the tail pipe.

@AuroraGirl I understand your way of thinking there and to some degree I agree, but keep in mind in a shop environment there isn't always the luxury of pulling all the spark plugs out and squirting in your decarb chemical of choice and leaving overnight. Of even fogging the engine and leaving overnight. I've fogged engines with AC delco X-66A (which by the way is bad ass stuff) and left them sit for an hour or so. Water works because it thermal shocks the carbon, basically making some of it brittle and then it comes off, or at least that's the theory. But again got to be careful with water!
 

AuroraGirl

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We are getting a little side tracked here considering the OP has an oil control issue not a carbon issue, but I'm enjoying the discussion.

I've heard good things about GM top engine cleaner, but have no personal experience. I remember back in the 90's having a 1980's something Ford in the shop. Had a pretty bad carbon issue, one of the guys had run a couple of bottles of whatever cleaner we were using at the time, through what we called an IV drip system into the PCV line. Still had issues. So I sat out in the parking lot and SLOWLY ran a gallon of water through the intake right down the carb. That did the trick. Like in @Matt69olds story there was a big grayish black streak of crap on the ground that came out of the tail pipe.

@AuroraGirl I understand your way of thinking there and to some degree I agree, but keep in mind in a shop environment there isn't always the luxury of pulling all the spark plugs out and squirting in your decarb chemical of choice and leaving overnight. Of even fogging the engine and leaving overnight. I've fogged engines with AC delco X-66A (which by the way is bad ass stuff) and left them sit for an hour or so. Water works because it thermal shocks the carbon, basically making some of it brittle and then it comes off, or at least that's the theory. But again got to be careful with water!
Water works because of the physical shock as you say, I was talking about chemicals specifically. I successfully did the water thing to my LTD kind of. It made a pile of coal but it didn’t stop so I eventually gave up :)

I haven’t done it to square but since it runs much more.. right.. I might just.

I don’t have time for that stuff either. I found that traction control activation in boost and a warped flex plate is all I need

I may be down a car right now...
 

SirRobyn0

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Water works because of the physical shock as you say, I was talking about chemicals specifically. I successfully did the water thing to my LTD kind of. It made a pile of coal but it didn’t stop so I eventually gave up :)

I haven’t done it to square but since it runs much more.. right.. I might just.

I don’t have time for that stuff either. I found that traction control activation in boost and a warped flex plate is all I need

I may be down a car right now...
This is where it would be good to know the science. Obviously a bottle added to a tank of gas is suppose to work a little at a time. But a chemical decarb down the intake? Maybe there is some thermal shock in there? I have no idea....
 

Ricko1966

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Yes this a little off the subject I was suggesting the water down the cylinders as a suggestion for cleaning the piston,cylinder and ring lands in an effort to get the rings to seal better. I do not know if anyone has suggested making sure the PCV valve and crancase ventilation hoses are all in good working condition. As in nothing plugged, pinched shut, stuck or collapsed.
 
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