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Author Topic: Valve stem oil usage?  (Read 472 times)

guest27834

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Valve stem oil usage?
« on: July 02, 2022, 04:19:49 AM »
Hello.
I have a new GTC 6/1 engine. It was test run, with fresh oil and water cooled from start.
I ran it intermittently over six months for an hour at a time with 50% load to break it in gently.
Now it's in its place of work and for the last two days it's been running at 70% load with a fresh oil change and tappet adjustment..
The engine started to make dripping black oil that puked out of the exhaust. I noticed that the rocker oil compartment seemed to be needing filling every day.
So my question is...what would be the normal rocker cover leakdown of oil, I am thinking that the factory valve stem oil seals may be shot already. I replaced the engine oil and made sure it wasn't overfilled so I dont think it's that. There is a very faint smoke when running at load now, and the engine is at 190f during it's run
Each day before starting, I have had to fill the rocker cover (valve spring) areas as they were empty,
Is this normal after 4 hours of use?
I suppose what I am asking generally is how much oil the rocker cover leaks down daily?
Thanks for any thoughts.

38ac

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Re: Valve stem oil usage?
« Reply #1 on: July 02, 2022, 11:59:20 AM »
Hello and welcome to the LEF :)

No, the engine should not use all of the valve stem oil in 4 hours. There is no seals on the valve stems, they rely on correct fit but India screws up several things that affect how much oil is consumed.
First thing is that on most, but not all India guides they decided it would be a good idea to drill a small hole in the side of the guides to let the oil run to the stem. If your guides are drilled then you cannot stop the oil usage without dissasembly and plugging them. I use a piece of lead shot with a tight fit.
Second thing is a loose fit of the valves in the guides. Original valve stems were 7/16" Some India valves are 7/16, some are 11mm. All of the guides are 7/16" if 11mm valves are installed in 7/16 guides(common) there is way too much cearance and oil consumption will be high.
Third thing is India will put a huge chamfer on top of the guides to act as a funnel,  another  bad move. I machine them flat and lightly deburr.
All of the fixes for oil consumption require head removal and machine work.  Very little oil is needed up there. The bulk of the engines that go through my little operation have never been oiled up top or seldom at best and they don't seem to suffer for it.
Last thing is the black goop in exhaust is not always from oil, it can also be from bad injector or bad injector timing and what appears to be oil is just unburned fuel and carbon mix. This is more of a problem with cold and lightly loaded engines than hot and heavily loaded.

When everything is done right up top you should see very little oil usage up top in an 8 hour run.

« Last Edit: July 02, 2022, 12:06:58 PM by 38ac »
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veggie

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Re: Valve stem oil usage?
« Reply #2 on: July 02, 2022, 03:27:01 PM »

Great explanation and fixes 38ac.
I had no idea those issues existed.

cheers,
veggie
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guest27834

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Re: Valve stem oil usage?
« Reply #3 on: July 03, 2022, 05:21:38 PM »
Thanks for your answers, and welcome, appreciate it.
The GTC does indeed have valve stem seals,
Next step will be to pull the head off an check everything, and replace the seals anyway while I'm in there.
Like I said the engine didn't do this till it was placed to work, maybe the load is causing the leak, but I will investigate and report back with what I find.
I suppose if it keeps happening I might clean the seals an stems and use a hydraulic grease in there .
Cheers.

38ac

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Re: Valve stem oil usage?
« Reply #4 on: July 03, 2022, 06:04:36 PM »
Indeed ??? thats a new one on me. Loading should have no effect on oil usage on a diesel, no vacuam changes to pull oil down the stems.  The top end knows nothing other than up and down motion. The cause will be interesting to hear about
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mobile_bob

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Re: Valve stem oil usage?
« Reply #5 on: July 03, 2022, 06:30:06 PM »
what are you using for an air cleaner?  if paper, maybe clogged with fine powder causing a vacuum on the intake?

just asking...

bob g
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guest27834

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Re: Valve stem oil usage?
« Reply #6 on: July 03, 2022, 06:46:11 PM »
The oil cleaner is the Lister oil bath with wire mesh inside.
That was my first port of call as I was thinking it may have been inhaling oil, alas that was not the case, (that would have made me happy as it would be a quick fix).

Today I noticed that the black oil coming from the exhaust is engine oil as it is quite thick, (I put a pail under to catch the drips, but the spray droplets have covered the grass, and are evident within 15 ft of the exhaust).

Yesterday I put just enough oil to fill to the bottom of the valve springs, so there was less oil out the exhaust,

Looks like there is no other way but to drain down the coolant tank and whip the head off for a closer look, (in my enthusiasm to get it all working, I forgot to iinstall a tank drain so that's enough of a reason to pull the head anyhow and install the drain at the same time).

Live and learn I suppose hahaaha.

Says all that, the engine charges my battery bank in two hours with the Delco 32 SI (170a alternator), and used less than a litre of deisel. My gas generator used about 6 litres of petrol in the same time, so saving about $8 a day in fuel so far.



mikenash

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Re: Valve stem oil usage?
« Reply #7 on: July 03, 2022, 07:24:11 PM »
The oil cleaner is the Lister oil bath with wire mesh inside.
That was my first port of call as I was thinking it may have been inhaling oil, alas that was not the case, (that would have made me happy as it would be a quick fix).

Today I noticed that the black oil coming from the exhaust is engine oil as it is quite thick, (I put a pail under to catch the drips, but the spray droplets have covered the grass, and are evident within 15 ft of the exhaust).

Yesterday I put just enough oil to fill to the bottom of the valve springs, so there was less oil out the exhaust,

Looks like there is no other way but to drain down the coolant tank and whip the head off for a closer look, (in my enthusiasm to get it all working, I forgot to iinstall a tank drain so that's enough of a reason to pull the head anyhow and install the drain at the same time).

Live and learn I suppose hahaaha.

Says all that, the engine charges my battery bank in two hours with the Delco 32 SI (170a alternator), and used less than a litre of deisel. My gas generator used about 6 litres of petrol in the same time, so saving about $8 a day in fuel so far.


Just a comment - to prevent a possible mis-diagnosis . . . One of my old CS 6/1s has a head-gasket leak, so a bit of water gets into the cylinder.  When it fires up after sitting for a while, it sprays small black droplets everywhere - not a lot of volume, but quite a mess.  Fwiw, I reckon this is water and soot/carbon

Could be wrong.  Won't know until I get around to getting the head off . . .

Cheers

guest27834

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Re: Valve stem oil usage?
« Reply #8 on: July 04, 2022, 04:32:16 AM »
Hello again.

So first of all, I want to apologize to 32ac,
There are in fact no valve stem oil seals on the GTC engines
The seals are on the camshaft ends, and that was my mistake.

Today I popped the head off the engine and took out the valves.
Both valves and sleeves are exactly 7/16", however I noticed that the exhaust valve was sticking.

The problem appears to be " the green goblin".

By that I mean the green paint that is slobbered over everything in these Indian engines.

The paint was 1/2" down the valve stem and there were flakes of paint all over the top of the valve head.

The exhaust valve had terrible scoring due to this and that must be where the oil was going.

The guides seemed unaffected, so the valve stems must be softer than the guides?

After cleaning everything up and removing as much paint as possible, I test fit some new spare valves and they seemed a nice fit.

The piston crown was 75% clean, and most carbon was towards the exhaust valve, so I think that the scoring must have been the problem..

So... Reassembled everything with the new valves and head gasket and then  placed a .177 flat nosed air rifle pellet on the piston to measure head clearance.

The head clearance was spot on after checking so I fastened it all back up and it started first time.

Minimal smoke at start up but gone after a few minutes,

The engine now has been running for five hours, and is at 200f,(warmer than before) and almost no smoke at 75% load

Interesting note, after the fact, but the engine always seemed to struggle when the ccv was changed to low compression, now it runs fine on low compression. So the exhaust valve must have been sticking from new.

Lesson for myself today...don't assume a new engine is ok till I've been inside and actually proved it so. And check facts before stating something that is incorrect*( sorry 38ac).

Thanks to everyone for the comments, it always helps motivate to action that which needs to be done!

32 coupe

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Re: Valve stem oil usage?
« Reply #9 on: July 04, 2022, 03:16:00 PM »

Good job !
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38ac

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Re: Valve stem oil usage?
« Reply #10 on: July 04, 2022, 11:40:37 PM »

Good job !


X2!   Thanks for posting your problem and the fix. Real world fixes are the best source of information for others
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dieselspanner

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Re: Valve stem oil usage?
« Reply #11 on: July 07, 2022, 08:06:51 PM »
Hi All

Just a swift point on the wearing of the valve stems versus the guides....

I was taught long back that the softer surface, in a situation like this,. allows the abrasive  particles to embed themselves and holds them as they wear the harder surface.

So, it may be worth checking the guides for contamination that will continue to abrade the new stems....

Cheers
Stef
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guest27834

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Re: Valve stem oil usage?
« Reply #12 on: July 08, 2022, 03:10:16 AM »
Thanks for all your comments,
I did clean out the valve stem guides really well before fitting the new valves.
Since doing the head the engine now has been put to retest for a shade over 14 hours at 75% load. The exhaust oil loss has reduced to a drop or two which is likely now just residue in the exhaust pipe. ( I intend to keep running the engine hot and loaded to monitor).

Fortunately it's been quite cloudy here in the forests of northern Saskatchewan and my solar array was lagging a bit. This of course has allowed me to test the generator setup now it's back together.

Thanks again for all the tips and great to know you guys are there to throw ideas about.
Cheers
Simon.