• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

//// 1985 International streaming oil out the blow by tube...WHY ? ////

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
HI All,

I have a 1985 International S1900 Truck with a DT 466 Engine, 5+2 tranny, and 173K miles.

I have always been impressed by how leak free this truck has been....The undercarriage was basically dry of all leaks.

In all fairness though, there was an old accumulation of oil on top of the valve cover towards the rear of the engine (where the blow by tube attaches to the top of the valve cover itself)....The oil there and towards the back of the engine was obviously old and baked dry....nothing wet or moist.

However, just yesterday, the truck started having massive amounts of blow by out the blow by tube / exhaust and used / leaked as much as 3 gallons within about 40 miles (good thing the driver had to do a stop because had it been a long highway run I'm sure the truck would have run out of oil before he would have known anything was wrong).

Anyways, the undercarriage of the truck was a mess so I thoroughly cleaned / degreased the engine area so I could see where the leak was....

Turns out the oil is leaking from the blow by tube (literally drip drip drip at a rate of approximately 2 drips per second so it is pretty fast....almost a small thin stream) and there was a fair amount blow by out the blow by tube and exhaust smoke to boot (not coal but oil burning).

The engine runs pretty smooth but has a slight shake to it more than normal....

What could cause this ? What is the cure?

It may have happened at one time before (as evidenced by the previous baked on oil) but I have driven it a lot with no issues until yesterday (Actually it was my helper driving it....I did notice as he drives sometimes he lugs the engine by up shifting too early or not splitting the shifts....

Could this be a cause of the issues ?

Thanks in advance for any and all help.

Andrew
 

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
The air filter is grayish (dirty not clean white) but the filter minder says restriction is OK (unless it's defective and stuck in the good range).

What to look for in the turbo?

There were no external leaks around the turbo ....

Thanks
 

Birken Vogt

Charter Member
Joined
Nov 30, 2003
Messages
5,305
Location
Grass Valley, Ca
If you disconnect the turbo drain and run it to a bucket with a hose, and plug off the engine side and then compare after you have disconnected the turbo drain, it should tell which it is coming from.
 

oceanobob

Senior Member
Joined
Jun 13, 2010
Messages
751
Location
oceano california
Occupation
general contractor
Would a coolant pressure test be of any troubleshooting value - this is suggested because I have been informed by the truck engine mechanics the typical diesel piston can tolerate no coolant, ergo my DT466 scalded a piston from a small coolant leak into that cylinder.
 

thepumpguysc

Senior Member
Joined
Mar 18, 2010
Messages
7,445
Location
Sunny South Carolina
Occupation
Master Inj.Pump rebuilder
Is it "making oil"? {check the dip stick}
The inj. pumps are notorious for getting fuel in the oil.. just a thought.
 

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
Is it "making oil"? {check the dip stick}
The inj. pumps are notorious for getting fuel in the oil.. just a thought.

HI,

Oil level is fine, no diesel leaking into the oil....

More recently, I've had to add oil due to the extra blow by and oil dripping out the blow by tube...

I've had to sideline the truck because of blow by and oil leakage
 

RZucker

Senior Member
Joined
Jul 7, 2013
Messages
4,077
Location
Wherever I end up
Occupation
Mechanic/welder
HI,

To keep this from happening to other engines, what causes a scuffed piston and liner ?
Way too many causes for me to list. One would be a dribbling injector, another would be a driver that likes to lug them down with full fuel with out downshifting. I did it once to my own service truck with a 7.8L Ford engine, a long coast down a steep hill with a steep upgrade at the bottom. cooled things down and then jumped on it hard, felt it right away. oops.
 

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
Is this the engine that overheated recently?

As far as I know this engine has never been overheated....

My 1999 truck from another thread is the one that overheated recently (sadly mobile mechanic said its probably a head gasket bit it could be a cylinder liner etc UGH....)...
 

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
Way too many causes for me to list. One would be a dribbling injector, another would be a driver that likes to lug them down with full fuel with out downshifting. I did it once to my own service truck with a 7.8L Ford engine, a long coast down a steep hill with a steep upgrade at the bottom. cooled things down and then jumped on it hard, felt it right away. oops.

sadly I do think he lugs the engine a bit....

Being used to tractor trailers he was keeping revs WAY too low (large Tractor trailer engines operate at revs way lower than a DT466 ) when I first started training him on the 5+2 ...

I told him to try to keep revs up a bit relative to what he seemed to want to do and as a minimum try splitting the 3 to 4th gear shift (there is a large jump gearing wise between 3rd and 4th) so as not to lug the engine...

Anyways, good to know.....this is our only stick shift truck so far and maybe our last because it's hard to find people who can drive them well.....
 

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
If you disconnect the turbo drain and run it to a bucket with a hose, and plug off the engine side and then compare after you have disconnected the turbo drain, it should tell which it is coming from.

HI,

I read this idea somewhere on the web BUT how would this actually cause blow by or oil coming out the blow by tube?

I'm thinking this has happened before since the area above the valve cover where the blow by tube attaches to the valve cover was oil covered probably 3/16 of an inch of dried crusty oil....I used a putty knife to help remove the crust so the engine degreaser could work its magic easier...

Being that the engine was fine for a long time while I owned it I wonder what the solution was before?


















Thanks
 

DB2

Senior Member
Joined
Jan 4, 2015
Messages
1,008
Location
Winnipeg MB Canada
Sounds like a damaged cylinder to me.
The accumulation of old oil in that area is normal on an engine that has been in service for a length of time. If you have the ability I would isolate the cylinders by cracking the injector lines one at a time to see if it reduces the blowby. If you find one that does that should eliminate the turbo as the problem.
 

DMiller

Senior Member
Joined
Feb 21, 2010
Messages
16,430
Location
Hermann, Missouri
Occupation
Cheap "old" Geezer
Agree with the others as to the old accumulation, to find the bad hole with the engine idling crack loose each injector line to stop fuel delivery to that cylinder then retighten, the one with the bad bucket will be obvious when you get there. Either little to no change or hammer like hell when fuel stops.

Blowby only occurs when either turbo boost or engine compression gets into the crankcase. One really wide swing could be if has air brakes where a air compressor going to hell and back CAN discharge into the crankcase.
 

Tenwheeler

Senior Member
Joined
Dec 15, 2016
Messages
870
Location
Georgia
DMiller is usually correct! We are all giving advise on a problem we have not seen first hand. All the holes could be worn out or have broken rings on several holes. That makes it more difficult. Start with the easiest first. Check turbo.
 

Andyinchville

Well-Known Member
Joined
Nov 24, 2006
Messages
108
Location
Charlottesville, VA
Occupation
Lawn Maintenance / Property Development
HI All,

Thanks for the suggestions to date ....Here is an update....

I checked the turbo for end play etc....I didn't notice any real play up or down or in or out so I assume (?) that means the turbo is OK ?....well at least the bearings..

I suppose there could be a bad oil seal in the turbo l BUT I don't see any oil leaking outside BUT I suppose a bad oil seal could also be internal and that may put oil into the air stream giving the appearance of burning oil (of course that doesn't explain the more recent "miss" I feel).

Anyways, I just thought, maybe I could or should check the turbo tubes for signs of oil in them to see if the turbo is blowing oil fumes into the air intake making for an oil burning of sorts.

Further research online also seems to indicate a failed gasket can cause turbo boost to enter the crankcase.....Supposedly the valve cover gasket and the intake gasket are such that a break in the wrong place can have turbo boost going into the crankcase! Anybody here able to confirm that or is that just a rumor?

As another test,

I run the truck today and cracked each of the injectors to help determine the problem cylinder(s).

The theory being, If I crack an injector, and the engine runs "rougher" then I know THAT cylinder was probably OK.

I did this for each of the 6 cylinders and the only cylinder to NOT make a difference in running when the injector was cracked was the one furthest in the back of the engine (when viewed from the front).

I suppose THAT isolates the cylinder to that one as far a the miss is concerned...

Given the new findings, what should I do next ?

I have thought of maybe buying an injector to see if that solves my problem (kinda costly with no guarantees of fixing the problem) BUT I suppose another test would be to swap injectors between 2 cylinders and see in my problem "moves" to another cylinder.

While I can understand an injector making a miss and possibly extra smoke out the tailpipe if not injecting correctly, It still doesn't explain the oil out of the blow by tube....maybe I'm double whammied with a blown gasket (turbo boost into crank case) and bad injector (miss and smoke out exhaust) ??

Thanks in advance for any other suggestions....

Andrew
 

RZucker

Senior Member
Joined
Jul 7, 2013
Messages
4,077
Location
Wherever I end up
Occupation
Mechanic/welder
HI All,

Thanks for the suggestions to date ....Here is an update....

I checked the turbo for end play etc....I didn't notice any real play up or down or in or out so I assume (?) that means the turbo is OK ?....well at least the bearings..

I suppose there could be a bad oil seal in the turbo l BUT I don't see any oil leaking outside BUT I suppose a bad oil seal could also be internal and that may put oil into the air stream giving the appearance of burning oil (of course that doesn't explain the more recent "miss" I feel).

The valve cover gasket issue only applies to the DT466E (intake manifold is in the Valve cover), with one dead hole and massive blowby I doubt swapping injectors is going to make much difference. A dead hole without the blow by? maybe. I think with reasonable surety you have a scuffed piston/liner in the dead hole. I'm even willing to bet money on this.

Anyways, I just thought, maybe I could or should check the turbo tubes for signs of oil in them to see if the turbo is blowing oil fumes into the air intake making for an oil burning of sorts.

Further research online also seems to indicate a failed gasket can cause turbo boost to enter the crankcase.....Supposedly the valve cover gasket and the intake gasket are such that a break in the wrong place can have turbo boost going into the crankcase! Anybody here able to confirm that or is that just a rumor?

As another test,

I run the truck today and cracked each of the injectors to help determine the problem cylinder(s).

The theory being, If I crack an injector, and the engine runs "rougher" then I know THAT cylinder was probably OK.

I did this for each of the 6 cylinders and the only cylinder to NOT make a difference in running when the injector was cracked was the one furthest in the back of the engine (when viewed from the front).

I suppose THAT isolates the cylinder to that one as far a the miss is concerned...

Given the new findings, what should I do next ?

I have thought of maybe buying an injector to see if that solves my problem (kinda costly with no guarantees of fixing the problem) BUT I suppose another test would be to swap injectors between 2 cylinders and see in my problem "moves" to another cylinder.

While I can understand an injector making a miss and possibly extra smoke out the tailpipe if not injecting correctly, It still doesn't explain the oil out of the blow by tube....maybe I'm double whammied with a blown gasket (turbo boost into crank case) and bad injector (miss and smoke out exhaust) ??

Thanks in advance for any other suggestions....

Andrew

It aint the turbo or an injector if you have a dead hole and blow by. It's the piston or liner in the dead hole.
ETA... I would have that injector checked to be sure its not a dribbler while you are rebuilding that engine.
 
Last edited:

DMiller

Senior Member
Joined
Feb 21, 2010
Messages
16,430
Location
Hermann, Missouri
Occupation
Cheap "old" Geezer
Will be time to pull either the oil pan(easiest to reinstall) or the head and have a internal look. Number six dead hole, most likely scored and rings destroyed where not building compression just sending it to the crankcase. Pan off roll the engine to 1&6 at tdc will be able to see cylinder wall damage/scores, is there is severe enough damage to the piston that will be really evident from the bottom, may be pieces in the pan.
 
Top