Engine/Transmission (1994 - 1998) Engine using oil, need opinions

[GAmes]

I just spent a bunch of hours and money fixing oil leaks. i had the IP rebuilt because it was leaking oil and I replaced the oil pan gasket. When I started it up I found the oil pressure sender was dripping, so I replaced it too. I then went on a 1600 mile test drive, 670 of it pulling an 11,000 pound 5er. The engine used a little over 2 quarts of oil. There is no oil in the coolant, BTW. I have read many times that a turbocharged diesel doesn't burn oil, and as you can see I have very little blowby. I'm thinking valve seals, they have about 600k on them. Here is the bottom of the engine and the blowby tube as seen from the rear. No oil anywhere.

 

[The patriot]

I only have just over 125K and I cant remember when the bottom of my truck has been that clean.

My truck has always "used" some oil... . from day one. Couple qts between changes isnt unusual for me.

Mine dont leak to the extent that I leave puddles of oil at redlights (or even if I idled it overnight somewhere) but there's a definite light coating under there.

 

[Missouri Mule]

Have you checked out your tail pipe for oil? Could be valves/valve seals or the turbo bearing seal on the exhaust side.

 

[GAmes]

Turbo is relatively new, no oil in the tail pipe. So one vote for the valve seals.

 

[SRadke]

Were you using the exhaust brake much? My 95 uses oil when I use the exhaust brake. I can't explain it exactly but when I use the brake heavy I find oil in the exhaust manifold.

-Scott

 

[ewcmr2]

Is two quarts in 1600 miles a change since you did the work on it or has it been using oil at that rate?
I wouldn't think a turbo diesel would suck (lack of vacuum, ya know) much oil past the valve guides. But they are cheap and easy to replace...

 

[NIsaacs]

Check the pressure side of the turbo, inlet & outlet on the intercooler and intake manifold inlet.



Nick

 

[HBarlow]

Gary,

It might finally be time to retire that engine. Almost 800,000 miles ain't bad.

Did something suddenly change or fail? It's odd that an engine using very little oil would suddenly begin consuming it at that fairly extreme rate. Did you install a bad gasket or make a mistake during the recent repairs?

 

[NIsaacs]

My guess is, the repair was done in an effort to control the oil use, that the assumption was mostly leakage. With the repairs done, the oil use is still evident and now Gary is looking elsewhere.



Nick

 

[GAmes]

My guess is, the repair was done in an effort to control the oil use, that the assumption was mostly leakage. With the repairs done, the oil use is still evident and now Gary is looking elsewhere.



Nick

That is exactly correct. Somewhere arund 750k oil consumption was about a quart every 3000 mles. The two obvious sources were the IP rod and the oil pan. Oil was dripping from the bottom of the transmission after after being on the road for a couple of weeks and I feared the rear main was leaking as well. Then during the last trip out it progessed from bad to worse quickly. Over the course of 11,600 miles it went from adding a quart every two or three days to a quart every day. Of course, the bottom of the truck was dripping oil everywhere and the sides were covered as well. I assumed the IP rod seal had totally failed, even though I know a little oil goes a long way and I had not washed it during the entire trip. I made up my mind to get the IP repaired and replace the pan gasket.



To lift the engine I disconnected the exhaust manifold from the EB, the turbo to intercooler V-clamp and had already removed the intercooler to intake tube when I had removed the IP. There was no trace of oil in any of them.



One added note, consumption is the same empty as loaded so boost isn't an issue. I rarely exceed 10 psi empty and while loaded I was bucking a head wind and stayed at 15 to 20 with bursts to 30, egt stayed below 1100.



So, is the general consensus valve seals, or do high mileage engines burn oil? I really do not relish removing springs in my gravel driveway (wifes '54 Ford restoration is in the garage).

 

[budnate]

I would suggest a good fuel cleaner, I like Sea Foam... . rings can get gummy over time and let blow by happen... . the truck I have now was a smoker and used a little oil when I got it, it showed 250K for miles... a couple tanks of seafoam later, mixed strong... and a couple good freeway runs later, it only puffs a little at cold start sometimes, and does not use oil anymore even towing and working over the hills... something to think about and try before you toss in the towel.



peace, B.

 

[Dieseldemon]

If the cleaner does not fix it do a compression test should be 350 psi or better.

 

[fest3er]

Have you tried removing the oil filler cap? Old engines are known for oozing oil when crankcase pressure gets too high, preventing the oil from flowing back to the pan, so it flows elsewhere. My oil consumption went from a quart every 500 miles back to a quart every 3000 after I replaced my filler cap with some redneck plastic plumbing.

 

[NIsaacs]

A diesel engine with worn cylinders/rings can burn oil, however, usually when they are that bad, high blowby is almost certain. Worn valve stem seals can also burn oil, usually in no power use, such as idling or going down hill, with blue smoke showing at the tail pipe.



Nick

 

[GAmes]

A diesel engine with worn cylinders/rings can burn oil, however, usually when they are that bad, high blowby is almost certain. Worn valve stem seals can also burn oil, usually in no power use, such as idling or going down hill, with blue smoke showing at the tail pipe.



Nick

I do not know what my exhaust color is when going down the road. I have a turn down tip, behind the mudflap and the exhaust is dissipated quickly. However, I am inclined to go with new valve seals. Pulling the injectors for a compression check is about the same amount of work as the seals, plus my gauge only goes to 300 which means I would have to buy another one. Besides, I don't have that much blowby, if I did there would be oil on the frame behind the vent tube. I am very reluctant to put a solvent in my fuel, and again, stuck rings are not likely anyway. One of the other forums I belong to suggest that if the dipstick seal is bad that blowby will cause oil to exit there. As an experiment I removed the dipstick and secured an old white washcloth at the opening to capture whatever came out. After 700 miles it was clean, so I reinstalled the dipstick. I will report the results of new seals.

 

[fest3er]

If it's valve seals, you should get slightly better fuel economy and possibly slightly better power. (OK, so it'd be nearly imperceptible. ) You should also be able to detect a slight difference when shutting the engine down. If there's oil coming in through the valves, shutdown should be slightly prolonged, and it ought to be kind-of rough/uneven (unless all the seals leak equally).

 

[GAmes]

If there's oil coming in through the valves, shutdown should be slightly prolonged, and it ought to be kind-of rough/uneven (unless all the seals leak equally).

I do have that. The engine shudders during shutdown, as in the old saying, like a dog crapping peach seeds:-laf

 

[The patriot]

I've always been led to believe sticky rings were more a result of the truck sitting, not running.

Judging from the miles on your truck, it dont sit that much.

 

[GAmes]

Gary,

It might finally be time to retire that engine. Almost 800,000 miles ain't bad.

I am passively looking for an engine to rebuild, just haven't found a deal. I expected that the engine would die around 750k due to the small power enhancements (all the million mile engines I have read about were still stock). If the seals don't cure the problem then I'll start looking a little harder, but the low blowby really has me puzzled. I put it on the dyno about 2 months ago and it had 3hp less than when I had 161k. Now that I have the IP rebuilt and tuned with a different fuel plate and governor springs I'm thinking of driving back to the dyno and have it run again.

 

[HBarlow]

If it's valve seals, you should get slightly better fuel economy and possibly slightly better power. (OK, so it'd be nearly imperceptible. ) You should also be able to detect a slight difference when shutting the engine down. If there's oil coming in through the valves, shutdown should be slightly prolonged, and it ought to be kind-of rough/uneven (unless all the seals leak equally).

That is an interesting bit of new information I had never heard before. It makes perfect sense as a possible clue to the cause of oil consumption in an engine with almost 800k miles of "work experience. "