Combustion Chamber Buildup

General engine tech -- Drag Racing to Circle Track

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cjperformance
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Re: Combustion Chamber Buildup

Post by cjperformance »

hoodeng wrote: Wed Jul 18, 2018 9:46 pm HD360 oil is one of the best rated air cooled engine mineral oils you can buy , typically synthetic oils only protect an engine when the capability of a mineral oil is surpassed, you are obviously not exceeding that oils capability.

The TC breather system operation was unchanged from 99 to 2017 the only difference was that the first were aluminium sections ,the second was plastic [prone to warping] the third was pressed steel ,all used the same umbrellas, separators and circuitry , probably the only thing that was a bit small was the orifice in the outlet bolts ,but that only tended to be a problem in engines that were breathing more than ideal.

Regular servicing and maintenance will see you get many more trouble free miles from your bike than you have so far.

Cheers.
Exactly why I use it! Most oils out there dont come near the flash point of the 360 oil. Fantastic stuff.
Yes im happy with the stock breather system, on an engine with no mechanical issues, blowby etc there is no need for change.
I was wondering if you knew/remembered what the oil burner engines were using oil or breather wise. ?
Craig.
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Re: Combustion Chamber Buildup

Post by user-23911 »

Tuner wrote: Wed Jul 18, 2018 5:50 pm
joe 90 wrote: Wed Jul 18, 2018 5:20 pm Carbon is carbon and oil deposits are oil deposits....not carbon.
Carbon is insoluble, it's a black powder.
Oil deposits are hydrocarbon.
There are no words. #-o

Do you not know the difference?

Not a lot different from deposits caused by burning leaded fuel.......those get called "carbon" too but it's lead.


Lead isn't carbon either.
Back in the old days you had to regularly "decoke" the combustion chambers and valves.
Coke is carbon .


So if the deposits look wet and shiney.......it's from oil burning , not from excess fuel.
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Re: Combustion Chamber Buildup

Post by naukkis79 »

joe 90 wrote: Thu Jul 19, 2018 12:24 am
Do you not know the difference?

Not a lot different from deposits caused by burning leaded fuel.......those get called "carbon" too but it's lead.


Lead isn't carbon either.
Back in the old days you had to regularly "decoke" the combustion chambers and valves.
Coke is carbon .


So if the deposits look wet and shiney.......it's from oil burning , not from excess fuel.
You are kidding, right?

Lead deposits are pretty easily differentiated from carbon as other is black and other white :D
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Re: Combustion Chamber Buildup

Post by Tuner »

joe 90 wrote: Thu Jul 19, 2018 12:24 am
Tuner wrote: Wed Jul 18, 2018 5:50 pm
joe 90 wrote: Wed Jul 18, 2018 5:20 pm Carbon is carbon and oil deposits are oil deposits....not carbon.
Carbon is insoluble, it's a black powder.
Oil deposits are hydrocarbon.
There are no words. #-o

Do you not know the difference?

Not a lot different from deposits caused by burning leaded fuel.......those get called "carbon" too but it's lead.


Lead isn't carbon either.
Back in the old days you had to regularly "decoke" the combustion chambers and valves.
Coke is carbon .


So if the deposits look wet and shiney.......it's from oil burning , not from excess fuel.
I spent the night at the Holiday Inn but I slept in the parking lot, so I guess I can only guess. Pardon me for using the word "carbon" as the generic term for "Hydro-Carbon Deposit". Had it been Lead or Tricresyl Phosphate I would have said so. The OP's pictures look (my guess is) too rich at light load. The subsequent pictures posted by hoodeng are mostly oil but some are too rich as well. I guess. This is the intervebz, I guess, you guess, we all guess, by guess and by golly, buy a vowel.
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Re: Combustion Chamber Buildup

Post by HDBD »

What threw me a curve was the chamber buildup. The beige color and it was fairly heavy and uniform. Customer said he mixed "one 110" in every tank of fuel. Not sure what that is, race gas or an additive.
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Re: Combustion Chamber Buildup

Post by Tuner »

HDBD wrote: Thu Jul 19, 2018 6:56 pm What threw me a curve was the chamber buildup. The beige color and it was fairly heavy and uniform. Customer said he mixed "one 110" in every tank of fuel. Not sure what that is, race gas or an additive.
It is fuel deposits, perhaps some oil, but primarily fuel deposit. It is too rich at light and moderate load. Is this engine carb or EFI?

Is the "one 110" perhaps an additive containing MMT? MMT makes a red/orange/tan deposit, depending on concentration of MMT and A/F.

(this came to me in a dream last night as I slept in the Holiday Inn parking lot ;-) ..)

TEL can make several distinct colors, depending on A/F (available oxygen), from dark red through orange and yellow to white. Red and orange from cooler engine temp and richer A/F, and yellow and white from higher engine temp and lean A/F. To prevent chamber deposits, other additives in leaded gasoline are compounds with chlorine, bromine and phosphorus. TCP can make yellow deposits and I don't know what makes green but I have seen green plugs, mostly out of 289-302 Fords for some reason. In the 60s Shell advertised "Now, With TCP !" and in engines burning that gas it was common to see "yellow cornflakes" in combustion chambers and a yellow deposit that stubbornly resisted removal with a wire brush in a drill motor. The corn flakes would flake off but the yellow layer underneath was hard as nails. Geezers may recall all this, but if you ain't over 70- years old you probably haven't seen this type of deposit because you haven't seen all daily driven cars burning highly leaded fuel, like in the late 60's.
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Re: Combustion Chamber Buildup

Post by hoodeng »

If you burn oil the black smoke that comes off it is carbon[call it whatever type of carbon you want] ,that smoke is not wet it is dry if combustion has occurred at a high enough temperature ,evident by the soot it covers everything with, this is because the oil has reached its flashpoint and started a chemical conversion due to combustion, so we get heat ,noxious gases and residue as a result [matter can not be created nor destroyed, just changed]The old term to 'de coke' is correctly to 'de carbon' an engine ,coke is a fuel manufactured by heating coal in the absence of air , Carbon comes in a number of elemental types ,the one we are dealing with is an ash residue precipitated by the combustion of a lubricating oil.[in this instance] There is also fuel combustion residue evident.The beige colour is also observed regularly.

The residue observed on some piston crowns is wet ,that is because it has not got hot enough to meet flash point ,the solid matter is the oil that has burnt and left a residue .The fuel burn issue leaving residue is more common in the early hemi type HD heads , the picture of the two Shovel pistons from the same engine side by side is a classic example of that type of engine. the piston on the left has a fuel combustion residue that would not surprise me in any of that type of engine ,the piston on the right however has a heavier coating of residue [i'll call it carbon] ,at the rear left of the piston the ash build up is heavier as this is the point of the bore most of the oil was passing ,right next to the heavier deposit is a radial clean patch ,this is where the fresh oil passing into the piston dome area has dissolved ,lifted ,cleaned, prevented from forming [whatever] the carbon ash residue ,i would expect the detergent content of the oil before being burnt [chemically converted] is contributing to this phenomena. If a Shovel engine presented here with a clear combustion chamber and piston crown i would hope is has just been on a very fast ride ,if not , it's about ready to melt.
Modern HD engines have relatively clean combustion areas.

This is getting away from the OP , I only service one brand of engine , so i only have a limited range of product to draw conclusions from ,but i see these chambers on a very regular basis , as i have the rest of the engine parts associated with a fault here ,my conclusions are drawn from the observation of all parts involved in the fault being investigated, be it excessive oil / fuel consumption ,noise , vibration or excessive heat or mechanical failure.
The engine in question is injected.
But all of the above is only my opinion.


Cheers
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Re: Combustion Chamber Buildup

Post by cjperformance »

Tuner, 1st i just have to ask why you are sleeping in a parking lot of a holiday inn? Surely the inn would have comfortable beds? :D
Re the green deposit on 289/302 fords, yes i have seen that as well but not since we (australia) could no longer buy pump leaded fuel (was called 'Super' here). The outter radius of the earth electrode and sometimes the top maybe .040" of the porcelain would have the greenish deposit which kind of looked like the green corrosion you see on copper pipes. I only remember seeing this on higher mileage stock 289/302w(not 351w?) and our 200/250ci 6 cylinder engines.
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Re: Combustion Chamber Buildup

Post by Tuner »

hoodeng wrote: Thu Jul 19, 2018 9:11 pm The engine in question is injected.
But all of the above is only my opinion.
Cheers
A narrow band O2 feedback system can be tricked with an Innovate LC-2 sensor controller or MTX-L A/F gauge, both of which have programmable analog output which can mimic a normal narrow band sensor voltage swing, so the ECU thinks all is normal, but at any (reasonable) A/F you choose. I've not personally done this with a Harley, but I have done several OBD 1 Chevys and they run sweet when you lean them out to between 16 or 17/1 in cruise mode. Every engine seems to have a different preference for how lean it will run, but pre-emissions carbed engines are mostly tuned to cruise between 16 and 17/1 so this ain't rocket science. Most NBO2 feedback systems toggle across stoichiometric as less than some throttle position, usually 50%, and run on a programmed tune at over 50% up to WOT, so tricking the O2 to run lean has no effect on high power and WOT A/F.

If anybody wondered why you see spark plugs that look rich and lean at the same time, it's because a NBO2 feedback system toggles the A/F between richer and leaner than stoichiometric and half the firing cycles are rich and the other half are lean.
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Re: Combustion Chamber Buildup

Post by hoodeng »

Pretty much all of the injected engines i do have either as my first preference a Dynojet Power vision or Dynojet single tune license ,whichever is most suitable for the stage of modification, i leave it to the guy that does my tuning though, these are his preferred tuners also , second is the SE tuner and that is only because the dealer fitted it to the bike when first purchased, although you have to be aware that some features can be disabled when the module is updated on the Harley website.
There are a number of things that can be preset within the modules to make the module think the engine is either larger or smaller or higher level of modification,so providing base maps more in line with what the engine will demand to start with on the dyno , this saves an ass chasing exercise after the first pull.

I know there are a myriad of tuners out there for Harley Davidson ,every couple of months there seems to be a new exciting one button does all, self tune product coming on the market, but there are a lot of people out there that are more than capable of tuning a bike to a standstill even with one of these fine products.

[disclaimer previously supplied] can the moderators create an icon that covers this ?


Cheers.
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