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dhanraha

blow by at vent tube

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Our old 3588 blows by vapors at the vent tube, and I know that is common for the 466. But if I am pulling it hard, like this spring on a 13 knife applicator, I may "use" 3 quarts of oil in a day. We always like to have a winter project, and I was thinking about tackling the engine. Two years ago I did a 414 and this year a 407. My only problem with going through this one is it doesn' t blow any blue smoke out the exhaust, which if it did, would indicate a problem with the rings, correct? Where is this oil going, and is it possible that what it needs more than anything is just the head worked over?

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It is entirely possible to have enough blowby past the compression rings to blow oil out of the crankase vent and not have exhaust smoke. Is the oil visibly blowing out of the vent?

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Rear main going bad isn't uncommon on those. Dad's 966 would "use" 2 qts a day till we put a new rear main in. Did that literally for years. After we put the main in, it'll use maybe 2 qts an oil change. However, you should have a puddle from that.

Chads

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3 quarts aint too bad. If I pull the 5488 hard on a warm day, it can use a gallon. The blowby is unbelievable, but the engine checks out fine. It's been this way for over 4000hrs.

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3 quarts aint too bad. If I pull the 5488 hard on a warm day, it can use a gallon. The blowby is unbelievable, but the engine checks out fine. It's been this way for over 4000hrs.

Same with ours, though about 3 qts is the limit. If you're pulling it hard sometimes it's hard to tell if there's more coming out the blowby or the stack!!! :blink:

Chads

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Does your 3588 have the valve cover mounted breather, or the block mounted breather (side breather)? The top breather engines originally had the wide-gap piston rings, and were known for more blow-by, even though the engine checked out okay. When we overhaul one, we put in the narrow-gap piston rings, even if the engine had a top breather, to reduce the blow-by.

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Thanks guys. Maybe I will just leave well enough alone. It does have the top breather. As far as oil visibly blowing out the vent, it is just a vapor. You can see it plain enough, but it doesn't look all that heavy. She still runs good, starts great, so maybe I will look around for another project.

I had a cat D6 9U and it would use a gallon a day working it hard. Sharp old guy told me to let it go, just add oil. Said he started out on one and it burnt just about that new. He said when they retired it that had went through the undercarriage twice, but had never touched the engine and it was still burning a gallon a day. "He said as long as you keep adding oil, they will run forever." I did and it did.

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just so you don't ever forget or loan it to someone :o ... you could just think of the gallon of oil as more expensive fuel :)

-ben

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some engines seem to use oil, others dont

Cat specify oil usage for the 3208 of 1litre per 8hrs

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I prefer an engine that burns at least a little oil. It makes me more confident that the top end is getting lubed proper. Is'nt the main reason for the smoke in the blowby cause the oil has made contact with hot surfaces? Usually up around the piston wrist pin and around the upper valve train are the hot spots right? So if the oil is making it way around those areas good, then a little oil "oxidation???" for lack of beter words, takes place. A little crankcase ventilation, and you have smoke in the blowby. I personally dont think anything of it other than I do watch it to make sure it does'nt change drasticly which may indicate other problems.

I was visiting with a mechanic about this one time and he mentioned using a higher quality of oil will reduce the consumption. Some of the newer engines with piston coolers and other things can really work the oil over. That's why they print oil specs for these engines and recomend using only oils that meet or exceed those specs.Well, the oil we use is unical sae 30. But it is just a general engine oil with general diesel engine specs. I cant help but wonder if he does'nt have something there. I have'nt gotten around to trying it yet, but maybe someday.

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We have had tractors that would use the first quart or 1/2 gal when filled to the "full" mark then not use any after that. Fill then back to the "full" and the oil level will drop on the stick within an hour or two. Leave them with the oil down on the dipstick & they would run several days that way. Foe shits & giggles give it a try & see what happens. Fill the oil to the "full" mark of a morning then check at noon. If down aways don't add oil but run it the rest of the day. If it's at the same level the next morning, don't add oil, run it part of the day and recheck.

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We have had tractors that would use the first quart or 1/2 gal when filled to the "full" mark then not use any after that.  Fill then back to the "full" and the oil level will drop on the stick within an hour or two.  Leave them with the oil down on the dipstick & they would  run several days that way.  Foe shits & giggles give it a try & see what happens.  Fill the oil to the "full" mark  of a morning then check at noon. If down aways don't add oil but run it the rest of the day.  If it's at the same level the next morning, don't add oil, run it part of the day and recheck.

That's interesting. I think you just put 2 and 2 together for me. Our 1680 has a 466 that when I change the oil, I can only get 17 quarts into it to be at the full mark. It does'nt burn but maybe 2 quarts every 100 hours. I wonder if the reason is just what you mentioned. The 1680 has a full reading a little lower than the 5488.

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My 5488 show enough blowby when pulling hard you can see it from the seat at times - tractor uses very little oil and runs fine. Also my 1660 has the same engine in it and it has alot of blowby by left side hood. My 1086 does what boog said it will use the first couple of quarts of oil and then very little oil between changes - I useally just leave it at the low mark. dougf

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