7.3 IDI excessive oil usage

Camp

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Goat...

Neither had I. My local International engine guys said it would be the CDR as that's the usual suspect and will channel a lot of oil through the intake, but that's not what's happening here. I'm going with the stuck oil rings after doing more online research. I tried to think of any other way oil could get from the crankcase into the cylinders while still holding that kind of compression.

Wild idea is these engines are known to cavitate and get holes in the cylinder walls, hence the DCA that's supposed to be added to the coolant, but those are usually coolant jacket issues. Never heard of a hole from an oil channel into a cylinder.

I decided to go with Seafoam for starters. Put a quart in the crankcase - 3 times the recommended amount - cranked it 3-dozen times in the hopes it would splash up to the oil rings. Then I put a cup or so in each cylinder, but it's hard to know whether it's running out the valves or filling cylinders without pulling valve covers and matching timing marks, so I'm figuring if I have time to do that now or not. And of course I'll blow the cylinders out before putting glowplugs back in. I'll run with the Seafoam in the oil or just idle it a bit, then change the oil before running it much. See if all that makes any difference. If it does, then I might get more thorough about it when I have more time as that'll tell me I'm on the right track.
 

Camp

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I see this from time to time when the CDR valve has been confirmed not the problem. Usually some broken or stuck oil control rings. No excessive smoke, just burns the oil as fuel. I have another one here sitting waiting for tear down with the same symptoms. I will bet money to find some broken/stuck oil control rings, and no severe carnage or wear elsewhere.
Kevin... when you said you've seen this before, have you ever seen this quantity of oil usage or anything close?
 

IDIBRONCO

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Sea Foam sure won't hurt. If it works, but you feel like there's more that could be done, you might want to try Diesel RX (if I got the name right) next. I've heard good things about that stuff.
 

Sparks-IDI

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Not saying it's a cure all, but do give the mystery oil a try. When I bought my truck a NA 7.3, it had sat a while. Compression averaged out at 405 lbs, 375 low 440 high. But there was considerable blow by. I noticed it would actually push my dipstick up out of the tube, a weeping rear main seal, and this was after I had already changed out the CDR. Engine ran just fine otherwise, couple, three quarts of oil every 300-500 miles. Now, using Chevron Delo 15W-40 plus quart of Marvel, with a new filter each time, I changed oil, filter, and Marvel at about 750-1000 mi interval three times to sort of flush the engine out, and now blow by is very minimal, weeping rear main nearly cleared up, dipstick stays put. If the rings were stuck before, they must have been freed up some now. Would be interesting to check the compression now to see where each cylinder stands.
I'd have to give Marvel Mystery Oil a thumbs up. I also favor Chevron Delo syn blend now. around here in Florida, at Walmart, it's cheaper than the other diesel oils.
 
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Camp

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Thanks for all the suggestions and info. I've learned a lot since starting this post.

Wound up rotating the crankshaft four different positions to get the pistons, 2 at a time, at BDC. Filled the cylinders with Seafoam and let it soak overnight. Drained the oil, refilled with Delo (yeah, the synth blend as it seems to have replaced the old Delo). Still smoking, but I haven't driven it anywhere, yet. It's possible it could loosen more crud on the rings up. I forgot to put a quart of Marvel in the oil change, so will either drain the oil and do that or run it a short while and add it with another oil change.

What I learned through all this is none of these products are designed to remove hardened carbon deposits. They're all made to prevent carbon build-up and may remove light deposits or crud that hasn't hardened, yet. Removing hardened carbon would either have to be done mechanically or with something so strong it would eat up other things in the engine ~ seals, soft metals, even steel, etc. For any of us who've chipped carbon off engine surfaces and wished there was something that would just eat it off, I, for one, haven't found anything, yet.

I watched a video on Youtube where a guy tried four pistons (removed) soaking in 4 different products and even with the one that worked the best ~ white vinegar ~ he had to knock on the rings to free them up.

Another guy used muriatic acid, but that's not something I'd want to put in my engine. I'm guessing for hardened carbon like I have on my rings the real fix is to physically remove the carbon with the pistons out.

That all said, if there's a chance I can improve this oil consumption without a teardown, I'm all for it. I've tried the Seafoam. I'll go with the Marvel next and maybe the Diesel RX. I doubt I'll do the whole putting it in the cylinder thing again as I don't have faith that's going to do it and it's a pain in the ass to do, but I'll definitely try adding stuff to the oil. Like some of you have seen, maybe letting some of this run in the oil a while can make a difference.

I also checked blowby after starting it up and there's none. I don't know if it takes some idling to build up blowby pressure. I'll check it again after running it some. Used to show some.
 
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Camp

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By the way, am I supposed to be "liking" your comments? Does that help you out? I don't pay much attention to that stuff.
 

Camp

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By the way, I don't know how long these threads stay open, but I'll let you all know if anything I've done made progress after driving the truck some. Maybe this could be a helpful conversation to have on here if this amount of oil usage isn't that common which it doesn't seem to be.
 

The_Josh_Bear

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You're burning so much oil I can barely wrap my head around it... I'm glad you checked your oil in time before it ate it all! Dang. I hope you get it figured out and it's not a broken oil ring. Hard to believe you have such good compression and low blowby with all this consumption. Crazy!

Some members don't use the "like" feature, some of us use them often for good tips or comments. It's certainly not necessary but does help a poster have feedback with what they are sharing on the forum.

I'm not sure if the threads archive or not...pretty sure you can look up just about anything from as far back as the site's been around! So yeah, keep us posted for sure. Some of us(like me) don't get around to finishing a thread for months or even years at times. But then we do and it's kinda fun to have the update necro thread. LOL
 

Nero

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As far as I'm concerned, it makes no difference either way.
I definitely enoy it for that juicy dopamine hit. :cheers:

But in regards to what cleaner to use, Something to think about is you'll be using this in an application where it will be in motion, subject to high forces which could work things loose. Seafoam has always been good to me in the past, but I won't discredit other things.
 
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