Engine Blow by

[cowboy44]

On a 100 hp International tractor, It has what I call blow by it does not use much oil, what causes this ?, how big of a concern is it? The motor runs good has plenty of power , starts easy

 

[bigbull338]

On a 100 hp International tractor, It has what I call blow by it does not use much oil, what causes this ?, how big of a concern is it? The motor runs good has plenty of power , starts easy

i dont know what you mean by blow by.but i take it is using some oil.so to me that means 2 things.1 blow gaskets or seals.or cracked rings on the pistons.so id check the seals an rings.

 

[Earl Thigpen]

"Blow by" usually means there is a compression leak past the rings and is most often accompanied by some oil consumption. My International 1485 has a little "blow by" but with a 25 quart pan the oil consumption is not hardly noticable between changes. I wouldn't worry about it until you start seeing blue smoke out the exhaust stack. Then you will know you have a bad ring problem and its time to rebuild.

 

[cornstalk]

How do you check for blow by ?

 

[somn]

How do you check for blow by ?

Just look for a large amount of oily air coming thru the valve cover vent tube.

 

[somn]

On a 100 hp International tractor, It has what I call blow by it does not use much oil, what causes this ?, how big of a concern is it? The motor runs good has plenty of power , starts easy

Excessive blowby can be caused by a bad PCV valve. I would have someone check that. We had an engine that one day just started showing excessive blowby we figued it was on its last leg. Ended up just being that valve was bad. I do not remember how much it cost to get it fixed but it was much cheaper than a overhaul.

 

[rmcva]

How do you check for blow by ?

I've seen diesel engines have some blow by and it would stop if you put a good load on the engine and work it hard. Putting around feeding cows or light duty work isn't what diesel engines were built for. Some don't take light duty well.


If your engine is strong and cranks well you might try working the snot out of it. It'll help reseat the rings. I bought a new tractor with a Perkins engine in it. Had no major tillage to do and was doing light duty work. It started to use a little oil. Since I had nothing to do at the time to load the tractor up I hooked it to a 11,000 dump truck. Got my son to ride the brake on the truck and pulled it for a mile up the road and a mile back. (had to stop and let the brakes cool off before the trip back) A white spot appeared on the top of the muffler. :lol: But the oil usage stopped right then and there.

 

[Wewild]

I've seen diesel engines have some blow by and it would stop if you put a good load on the engine and work it hard. Putting around feeding cows or light duty work isn't what diesel engines were built for. Some don't take light duty well.

I don't think so. Ours do just fine. The youngest one is from 1973 and we quit row crops in the mid 80's.

 

[rmcva]

I've seen diesel engines have some blow by and it would stop if you put a good load on the engine and work it hard. Putting around feeding cows or light duty work isn't what diesel engines were built for. Some don't take light duty well.

I don't think so. Ours do just fine. The youngest one is from 1973 and we quit row crops in the mid 80's.

That's why I wrote "Some don't take light duty well." I didn't say all.

 

[ALACOWMAN]

On a 100 hp International tractor, It has what I call blow by it does not use much oil, what causes this ?, how big of a concern is it? The motor runs good has plenty of power , starts easy

id check the crank case filter if its got one. ive seen them blow rear main seals or the dip stick plumb out because of stopped up filters. other than that i wouldnt worry about it

 

[Stocker Steve]

Excessive blowby can be caused by a bad PCV valve. I would have someone check that. We had an engine that one day just started showing excessive blowby we figued it was on its last leg. Ended up just being that valve was bad. I do not remember how much it cost to get it fixed but it was much cheaper than a overhaul.

I just replaced a bad PVC valve but still have blow by when I remove the oil fill cap. I have been running 10W-40 oil. Is there any value in a heavier oil, or in a straight oil, before doing an overhaul?

 

[JHH]

Excessive blowby can be caused by a bad PCV valve. I would have someone check that. We had an engine that one day just started showing excessive blowby we figued it was on its last leg. Ended up just being that valve was bad. I do not remember how much it cost to get it fixed but it was much cheaper than a overhaul.

I just replaced a bad PVC valve but still have blow by when I remove the oil fill cap. I have been running 10W-40 oil. Is there any value in a heavier oil, or in a straight oil, before doing an overhaul?

If your talking about oil for a tractor I would recommend 15w 40 . I think 10w-40 is a little light for a tractor. JHH

 

[Stocker Steve]

If your talking about oil for a tractor I would recommend 15w 40 . I think 10w-40 is a little light for a tractor. JHH

You see a lot of straight 30 and 40 weight oil on the farm store shelf. Where does that stuff get used?

 

[tytower]

Excessive blowby can be caused by a bad PCV valve. I would have someone check that. We had an engine that one day just started showing excessive blowby we figued it was on its last leg. Ended up just being that valve was bad. I do not remember how much it cost to get it fixed but it was much cheaper than a overhaul.

I just replaced a bad PVC valve but still have blow by when I remove the oil fill cap. I have been running 10W-40 oil. Is there any value in a heavier oil, or in a straight oil, before doing an overhaul?

Modern oils are all detergent oils and clean down the insides of the engine. A non detergent oil if you can get it at 40W and up is useful because the burnt oil builds up in the rings and improves compression. Ive mixed 120 gearbox oil with thinner for the same result but I think now one of those cans you shove down each cylinder and burn in does much the same thimg. But don't do it if you really want to keep the unit . Repair it properly cause the above is just short ten as the excess wear lets it wear faster anyway.

 

[tytower]

Excessive blowby can be caused by a bad PCV valve. I would have someone check that. We had an engine that one day just started showing excessive blowby we figued it was on its last leg. Ended up just being that valve was bad. I do not remember how much it cost to get it fixed but it was much cheaper than a overhaul.

I just replaced a bad PVC valve but still have blow by when I remove the oil fill cap. I have been running 10W-40 oil. Is there any value in a heavier oil, or in a straight oil, before doing an overhaul?

Modern oils are all detergent oils and clean down the insides of the engine. A non detergent oil if you can get it at 40W and up is useful because the burnt oil builds up in the rings and improves compression. Ive mixed 120 gearbox oil with thinner for the same result but I think now one of those cans you shove down each cylinder and burn in does much the same thimg. But don't do it if you really want to keep the unit . Repair it properly cause the above is just short tern as the excess wear lets it wear faster anyway.