smoke

Ranch_Hand_Supp · Jun 1, 2006

( ( The tube on top of the valve cover has nothing to do with the engine oil pressure or engine oil gauge reading. )

This is nothing I've personally witnessed Ron. But others HAVE reported tracking down a low oil pressure reading to a kink in that piece of clear hose. It's been mentioned in this forum and in others. Straighten out the kink, oil pressure indication on the gauge returns to normal. Don't ask me to explain it, I'm only reporting what I've read here and on other help sites.

//greg// )

//greg// , I don't know what to tell ya, not even sure why you are trying to give me your reason for your posting ??? I agree with RonMars post .... pretty good explaination of how the system works I think, based on my hands on experiance.

Maybe some of the members that posted crank case pressure effects engine oil pressure will chime in??? maybe they can explain it ??.

It's an opinion board ..... it's up to the reader to determine what they want to believe or do, IMHO..

Pauly, another thought I have ..... you have 170 hours, valve adjustment is in order if you have not already done so.

Ronald
Ranch Hand Supply

Ranch_Hand_Supp · Jun 1, 2006

( ( The tube on top of the valve cover has nothing to do with the engine oil pressure or engine oil gauge reading. )

This is nothing I've personally witnessed Ron. But others HAVE reported tracking down a low oil pressure reading to a kink in that piece of clear hose. It's been mentioned in this forum and in others. Straighten out the kink, oil pressure indication on the gauge returns to normal. Don't ask me to explain it, I'm only reporting what I've read here and on other help sites.

//greg// )

//greg// , I don't know what to tell ya, not even sure why you are trying to give me your reason for your posting ??? I agree with RonMars post .... pretty good explaination of how the system works I think, based on my hands on experiance.

Maybe some of the members that posted crank case pressure effects engine oil pressure will chime in??? maybe they can explain it ??.

It's an opinion board ..... it's up to the reader to determine what they want to believe or do, IMHO..

Pauly, another thought I have ..... you have 170 hours, valve adjustment is in order if you have not already done so.

Ronald
Ranch Hand Supply

Soundguy · Jun 1, 2006

Here's an educated guess from a non chinese tractor owner.

Secondary unrelated effect. I.E. the act of repair the kinked line disturbed some other thing.. possibly a loose wire in the wireing harness, and this corrected the oil pressure reading.

I've seen 'similar' issues on other tractors. I was doing a steering repair onmy 8n.. has a dash mounted ammeter.. a plastic cased 'new' one, vs the oem NLS metal cased ones. After putting the dash back on.. no continuite thru ammeter.. remove ammeter.. check with meter -fine-. reinstall.. nothing.

Boiled down to a loose connection in the ammeter.. and when it was firmly mounted tot he dash, which have about a .5 degree bend to it, it put just enough pressure ont he ammeter to break the connection. I actually diagnosed this by leaving the lamps on, and beginning to remove the ammeter.. as soon as i loosened the retainin nuts so that no pressure was on the plastic housing, the meter registerd and lamps came on. It was a 9$ part that took me 4 hours to fix...

I wonder if the act of unkinking this line in some way jiggles something.. like an oil sender.. or dash ground strap.. or soemthing that magically makes the oil gauge work after this?

again.. a really WAG...

Soundguy

Soundguy · Jun 1, 2006

Here's an educated guess from a non chinese tractor owner.

Secondary unrelated effect. I.E. the act of repair the kinked line disturbed some other thing.. possibly a loose wire in the wireing harness, and this corrected the oil pressure reading.

I've seen 'similar' issues on other tractors. I was doing a steering repair onmy 8n.. has a dash mounted ammeter.. a plastic cased 'new' one, vs the oem NLS metal cased ones. After putting the dash back on.. no continuite thru ammeter.. remove ammeter.. check with meter -fine-. reinstall.. nothing.

Boiled down to a loose connection in the ammeter.. and when it was firmly mounted tot he dash, which have about a .5 degree bend to it, it put just enough pressure ont he ammeter to break the connection. I actually diagnosed this by leaving the lamps on, and beginning to remove the ammeter.. as soon as i loosened the retainin nuts so that no pressure was on the plastic housing, the meter registerd and lamps came on. It was a 9$ part that took me 4 hours to fix...

I wonder if the act of unkinking this line in some way jiggles something.. like an oil sender.. or dash ground strap.. or soemthing that magically makes the oil gauge work after this?

again.. a really WAG...

Soundguy

JohnS · Jun 2, 2006

I have seen the posts greg mentions. I couldn't come up with how it would effect oil pressure, either. Only thought was what soundguy mentioned. Anyone with a y385 can go do a test and kink their hose to see if it does effect oil pressure.

Let me throw this out for discussion: If the inlet crankcase filter is totally plugged up, and then the plastic hose became kinked, would that build up enough pressure or vacuum to possibly effect oil pressure? It would seem to me, that it would have to create allot of pressure, but not sure. Thoughts???

JohnS · Jun 2, 2006

I have seen the posts greg mentions. I couldn't come up with how it would effect oil pressure, either. Only thought was what soundguy mentioned. Anyone with a y385 can go do a test and kink their hose to see if it does effect oil pressure.

Let me throw this out for discussion: If the inlet crankcase filter is totally plugged up, and then the plastic hose became kinked, would that build up enough pressure or vacuum to possibly effect oil pressure? It would seem to me, that it would have to create allot of pressure, but not sure. Thoughts???

JohnS · Jun 2, 2006

RonMar,

Theory sounds good and is how I understood positive crankcase ventilation (pcv). Do the newer epa engines have a pcv valve? My non-epa y385, I believe is just a hose attachment to valve cover. Otherwise it will be pulsing all the time. ie, there isn't an intake valve open all the time. You can feel the pulses by holding your hand near/over the inlet to air filter housing. I think it works the same as you described, just not a constant vacuum. My 350 SBC in my boat, does not have pcv valves. Just straight through hoses, up to flame arrester (carb intake/air filter). Gases are drawn off only when air is moving fast enough, only I don't believe there is any crankcase inlet air filter.

I believe this mainly an emissions function. Blowby will have very little unburned fuel, same as what is exiting via exhaust. Never heard of any 70's car motor blowing because it didn't have pcv, and gas vapors are much more combustable than diesel. All they had were foam breathers in valve covers. At least not at stock rpms.

JohnS · Jun 2, 2006

RonMar,

Theory sounds good and is how I understood positive crankcase ventilation (pcv). Do the newer epa engines have a pcv valve? My non-epa y385, I believe is just a hose attachment to valve cover. Otherwise it will be pulsing all the time. ie, there isn't an intake valve open all the time. You can feel the pulses by holding your hand near/over the inlet to air filter housing. I think it works the same as you described, just not a constant vacuum. My 350 SBC in my boat, does not have pcv valves. Just straight through hoses, up to flame arrester (carb intake/air filter). Gases are drawn off only when air is moving fast enough, only I don't believe there is any crankcase inlet air filter.

I believe this mainly an emissions function. Blowby will have very little unburned fuel, same as what is exiting via exhaust. Never heard of any 70's car motor blowing because it didn't have pcv, and gas vapors are much more combustable than diesel. All they had were foam breathers in valve covers. At least not at stock rpms.

Egon · Jun 2, 2006

Think I'd pull the head as chances are [Unfortunetly ] there will be an internal problem. Catch it before it can get worse or do serious damage.

Egon /forums/images/graemlins/grin.gif

Egon · Jun 2, 2006

Think I'd pull the head as chances are [Unfortunetly ] there will be an internal problem. Catch it before it can get worse or do serious damage.

Egon /forums/images/graemlins/grin.gif

Egon · Jun 2, 2006

There is always a dip stick hole. /forums/images/graemlins/grin.gif

Egon /forums/images/graemlins/grin.gif

Egon · Jun 2, 2006

There is always a dip stick hole. /forums/images/graemlins/grin.gif

Egon /forums/images/graemlins/grin.gif

JohnS · Jun 2, 2006

The dipstick on the Y385 is a rod into a threaded cap. Dipstick screws down. It may not be 100% airtight, but it is nothing like a typical push-in car dipstick.

There could be other outlets for crankcase pressure, though.

JohnS · Jun 2, 2006

The dipstick on the Y385 is a rod into a threaded cap. Dipstick screws down. It may not be 100% airtight, but it is nothing like a typical push-in car dipstick.

There could be other outlets for crankcase pressure, though.

RonMar · Jun 2, 2006

(
I believe this mainly an emissions function. Blowby will have very little unburned fuel, same as what is exiting via exhaust. Never heard of any 70's car motor blowing because it didn't have pcv, and gas vapors are much more combustable than diesel. All they had were foam breathers in valve covers. At least not at stock rpms.

)

What you say about blowby having very little unburned fuel is correct for gas engines. In diesels, they will pass unburned fuel past the rings and into the oil. On lightly loaded engines, you can actually run into problems with the lube oil being diluted by the ammount of diesel fuel making it into the oil. On a hot engine, this lighter diesel can make it back into vapor form and reach combustible levels if not removed. On all the large marine diesels I have operated, they all had crankcase exhausters(large electric blowers) that kept the crankcase under vacume. This level of vacume was monitored electronically. You could not start the engine and the engine would shutdown automatically if there was not enough vacume in the case. On my last ship while steaming across the equator, we would be running near max temperatures and near max load and the added blowby combined with vacume leaks around the engine would keep us very near the vacume shutdown point on the engines.

Crankcase explosion was also regularly on our required drill scenario listing as it tends to spread hot lube oil all over the engine room when it blows the crankcase inspection ports off. I have never personally experienced one but they do happen.

RonMar · Jun 2, 2006

(
I believe this mainly an emissions function. Blowby will have very little unburned fuel, same as what is exiting via exhaust. Never heard of any 70's car motor blowing because it didn't have pcv, and gas vapors are much more combustable than diesel. All they had were foam breathers in valve covers. At least not at stock rpms.

)

What you say about blowby having very little unburned fuel is correct for gas engines. In diesels, they will pass unburned fuel past the rings and into the oil. On lightly loaded engines, you can actually run into problems with the lube oil being diluted by the ammount of diesel fuel making it into the oil. On a hot engine, this lighter diesel can make it back into vapor form and reach combustible levels if not removed. On all the large marine diesels I have operated, they all had crankcase exhausters(large electric blowers) that kept the crankcase under vacume. This level of vacume was monitored electronically. You could not start the engine and the engine would shutdown automatically if there was not enough vacume in the case. On my last ship while steaming across the equator, we would be running near max temperatures and near max load and the added blowby combined with vacume leaks around the engine would keep us very near the vacume shutdown point on the engines.

Crankcase explosion was also regularly on our required drill scenario listing as it tends to spread hot lube oil all over the engine room when it blows the crankcase inspection ports off. I have never personally experienced one but they do happen.

JohnS · Jun 2, 2006

Ron,

Thanks for additional explaination. I won't argue with you Navy guys! /forums/images/graemlins/wink.gif Those diesels can be huge! I think I can rationalize why that may be, but I will chew on it some more, before posting any more JohnS theory. /forums/images/graemlins/blush.gif

JohnS · Jun 2, 2006

Ron,

Thanks for additional explaination. I won't argue with you Navy guys! /forums/images/graemlins/wink.gif Those diesels can be huge! I think I can rationalize why that may be, but I will chew on it some more, before posting any more JohnS theory. /forums/images/graemlins/blush.gif

greg_g · Jun 2, 2006

( I have seen the posts greg mentions. I couldn't come up with how it would effect oil pressure, either. Only thought was what soundguy mentioned. Anyone with a y385 can go do a test and kink their hose to see if it does effect oil pressure.

Let me throw this out for discussion: If the inlet crankcase filter is totally plugged up, and then the plastic hose became kinked, would that build up enough pressure or vacuum to possibly effect oil pressure? It would seem to me, that it would have to create allot of pressure, but not sure. Thoughts??? )

Wish I still had mine to try your little experiment, but there are still plenty of members that might volunteer. I'm straying off topic here, but hopefully not far enough to distract attention from Pauly's original issue.

I do know that the OE oil pressure sending unit represents ground to the OE oil pressure gauge. Internal to the OPSU is a diaphram that - when at rest - presents roughly a zero ohm path to the engine block and eventually to the negative post of the battery. Movement of that diaphram represents resistance to ground, which is reflected by needle movement in the gauge. The degree to which moving oil presses on the diaphram increases or decreases the resistance to ground, reflected then by higher or lower oil pressure indications on the gauge.

That much is known, the following is a SWAG. I'm having a little trouble with the fact that the clear plastic tubes on my Jinmas never got dirty inside, as you might expect if they were carrying oil/fuel contaminated fumes. Therefore I'm going to go a different route from RonMar with this, suggesting that the clear vinyl tube is just a pressure equalizer. And that the oil breather bolted to the lower side of the block truly breathes; that is, permits the passage of air in both directions. Inhale/exhale, depending upon the difference in atmospheric pressure inside and outside the crankcase. And that the screen inside just catches the airborne when the crankcase is "exhaling". The clear tube then, would be unrelated to the breather - merely making sure that pressures under the valve cover were roughly equal to that in the crankcase. An equalizer tube.

OK. The engine's now breathing, and the oil pressure's currently constant. So now let's kink that clear tube, so that the pressure on top is no longer the same as the pressure below. I could see this situation lowering the atmospheric pressure inside the crankcase, without lowering the ACTUAL oil pressure. But at the same time this negative pressure could pull back on the OPSU diaphram, changing the resistance to ground and giving a false representation of lowered oil pressure on the gauge. Straightening out the kink equalizes the pressure again, removing the negative pressure force from the diaphram - oil pressure indication returns to normal.

Please remember a lot of this is SWAG, so please don't beat me up too hard if I've overlooked something obvious.

//greg//

greg_g · Jun 2, 2006

( I have seen the posts greg mentions. I couldn't come up with how it would effect oil pressure, either. Only thought was what soundguy mentioned. Anyone with a y385 can go do a test and kink their hose to see if it does effect oil pressure.

Let me throw this out for discussion: If the inlet crankcase filter is totally plugged up, and then the plastic hose became kinked, would that build up enough pressure or vacuum to possibly effect oil pressure? It would seem to me, that it would have to create allot of pressure, but not sure. Thoughts??? )

Wish I still had mine to try your little experiment, but there are still plenty of members that might volunteer. I'm straying off topic here, but hopefully not far enough to distract attention from Pauly's original issue.

I do know that the OE oil pressure sending unit represents ground to the OE oil pressure gauge. Internal to the OPSU is a diaphram that - when at rest - presents roughly a zero ohm path to the engine block and eventually to the negative post of the battery. Movement of that diaphram represents resistance to ground, which is reflected by needle movement in the gauge. The degree to which moving oil presses on the diaphram increases or decreases the resistance to ground, reflected then by higher or lower oil pressure indications on the gauge.

That much is known, the following is a SWAG. I'm having a little trouble with the fact that the clear plastic tubes on my Jinmas never got dirty inside, as you might expect if they were carrying oil/fuel contaminated fumes. Therefore I'm going to go a different route from RonMar with this, suggesting that the clear vinyl tube is just a pressure equalizer. And that the oil breather bolted to the lower side of the block truly breathes; that is, permits the passage of air in both directions. Inhale/exhale, depending upon the difference in atmospheric pressure inside and outside the crankcase. And that the screen inside just catches the airborne when the crankcase is "exhaling". The clear tube then, would be unrelated to the breather - merely making sure that pressures under the valve cover were roughly equal to that in the crankcase. An equalizer tube.

OK. The engine's now breathing, and the oil pressure's currently constant. So now let's kink that clear tube, so that the pressure on top is no longer the same as the pressure below. I could see this situation lowering the atmospheric pressure inside the crankcase, without lowering the ACTUAL oil pressure. But at the same time this negative pressure could pull back on the OPSU diaphram, changing the resistance to ground and giving a false representation of lowered oil pressure on the gauge. Straightening out the kink equalizes the pressure again, removing the negative pressure force from the diaphram - oil pressure indication returns to normal.

Please remember a lot of this is SWAG, so please don't beat me up too hard if I've overlooked something obvious.

//greg//