I do not think it is a ticking time bomb regarding the oil usage. If it isn't lean, oil usage seems like the only side effect.

 

Several of these guys sound like they know engine building....

But not one mentioned that unless you have a really 'good' reason to pull the heads... it's better NOT to pull them.

The reason is although you will torque the head bolts back to specs., the bolts will not 'pull' the metal back to it's original position as when the heads were torqued the first time.
This effect is small but it does exist. The rings will have to 'seat' a second time to the changed shape of the cylinders.

You probably won't notice much difference in performance. This 'may' cause the engine to consume a greater amount of oil than it did before the heads were pulled. The compression may be slightly less than before the heads were pulled.

The marks in the cylinders were likely caused by some small 'grit' that got between the piston skirt and the cylinder wall.
Without checking the ring ends it's just a guess as to whether the ends of the rings caused the marks.
A small piece of carbon could have wedged between the piston and cylinder wall. The marks are nothing to worry about.

Get a tap and run it into ALL the head bolt holes in the block before you put the heads back on.
Don't forget to put a sealer on all the head bolts that go into the water jacket. Just put sealer on all them because the ones that don't go into the water jacket need to be sealed so oil won't seap past them.

The oil consumption could also be caused by the valve stem bores or seals.
you may want to check them or replace the seals while the heads are off.

BTW.... Leave the carbon that's built up on the pistons on them.....
If you "MUST" clean them..... pack some paper towels down around the pistons to keep that garbage' from falling in the crack.
Best thing to do is DONOT CLEAN the piston tops....
I know everybody WANTS to but... just don't do it. You take a BIG chance of some of that stuff falling down by the piston and causing more of those marks you see.

Again...... my .02 ..... Do Not Pull The heads on a running engine unless you need to pull them for 'cause'. Don't pull them just to 'take a look'.
That advice is for 'next time'.......

 

Thanks guys for all the feeback.

Here is a update:

I talked to my engine builder, he whas whery understanding.
He told me that the correct stone whas used for the rings, he used the recomendation from ring manufacture. The rings whas file to fit type, and he use the right ring gap. He even mailed the company to verify the end gap becuase he thougt the gap that the manufacture gave in the manuel that come with pistons where to big (proge forge pistons ). But after he talked to probe he did what they told him.
Regarding the scuffing on the bore he told me it whas "normal", and regarding the scratches he needed to se that for him self, so I have to wait for a verdict on that one.
The piston the wall clearance whas also within the spec from the manufacture.

We came up with some possible explanation for the oily goo on the pistons.
He told me to look over the cylinderheads. And what I saw whas that on 7 of the intake vavles I got a spot ( the size of a fingernail ) of burned oil on them. And that could indicate bad valve seals or bad vavleguides. The oil "spots" on the valves where all on the outeredge of the valve, towards the lifter valey side. And that could also indicate a intake leak, that the intake whas sucking oil from the lifter valey area. As I use a converted LT1 intake there could be a alignment probleme agains the heads. That is a interesting thing to look up.

But if we cant find any probleme with the heads or the intake. And if we can verify that the rings do have alot of blowby he will ofcourse re-hone or bore the block for free. He has worked with engine all his life and good a good rep here in Sweden, so he is whery keen on his reputation. And as a owner of Swedens largest corvette forum I can make som damage

I keep you posted.

Regards

ps: thanks for the tips regarding the heads Jim ..

 

I did not see any mention of torque plates used or not used. Rehoning and reringing, is not worth doing in my opion, without using torque plates. The results will be the same without. Insist on it.

 

Yes ofcourse, that I will..

 

My wife say's I tend to repeat myself
Just wanted to drive that point home. The newer (after 1975) blocks are considered lightweight. They are so flimsy because of this. In the old days racers use plates to get the edge on the competition. Now it is absolutely required just to make a round cylinder. When I was shafted by an engine builder, all 8 bores were dead ***** perfectly round without the torque plate. 4.030 was the size. After torquing on the plate all cylinders became out of round. 2 of them were .003 tight at the top. He claimed that they were used during honing, I proved they were not. It took a phone call from my attorney to convince him he was wrong. This was 10 years ago.My current builder is honest.

 

What are you view on the possible "oil" probleme I mention abow. Not to far fetch and surly interesting enough to examin?

 

Pete,
Man, that is terrible. I honestly thought that the days of just using a hone and a 1/2"drive drill by hand were over. Seeing there are guys out there that are still doing that by hand without plates etc. and telling a customer otherwise, that is just plain wrong and deserve whatever due process of the law. Glad to hear you had that covered. I imagine there are many that never checked, and then had some real issues.

 

I do not wish to imply his machinest is unethical. Mine clearly was. Installing a torque plate takes time. When rushed or behind, some tend to "forget" to install it. I own a bore guage and check everything I have done.

 

Regarding if my engine builder is "unethical" or not Is a issue that I will handle mysefl, and thats not really a topic that should be discussed here. So far he is whery understanding. Time will tell..

So back to the topic at hand. I would really love to hear som feedback regarding the oil issues I posted abow. To start, is there some way I can test the valve seals myself. Or do I need to take the heads to a mech shop with proper gear for that?

Regards

 

Although I have never used or saw one, the service manual shows a tool that slips over the top of the retainer and applies vacuum. I believe this is a test for the o-ring on the valve stem. Seals are easy to check. If they are soft, look good and are firmly attached to the guide(pc type) they should be fine. Umbrella seals just sit there. I would do a valve guide check while it is apart. Excessive guide clearance will contribute to oil being pulled past the valve guide seals.

 

I understand, and it wasn't taken that way. It just makes me think about the time before I had mics. and some bore gauges etc. I know that many DIY's don't have any precision tools etc.and have put to their faith in a machinist without checking the work.
Ultimately, unless one has the tooling we are all suspect to having someone "forgetting" or being rushed. I have to depend on machinists to do the work. Finding guys who will spend the time is certainly worth it. Like yourself, I still double check everything before assembly (if for nothing else piece of mind).

devilfish, sorry not trying to take your thread off topic.

 

I agree. I did not mean to either. I just wanted to make the point that no torque plate use is quite common and promotes terrible ring seal, therefore oil consumption. May people chase this problem when it is often something as easily missed as this.

 

your engine builders answer that he ''used the stone recommended by the ring manufacturer'' implies to me that he did use the right ''grit'' to hone the cylinder (several different grits or coarseness are available and different types of ring--moly,plain,chrome,etc--req different grit) but also sounds like deburring the ends with a stone is an unknown to him as his answer went off topic.

but i've torn down race motors that were feature winners that looked much worse than yours (not originally built by me)

is yours perfect?--no
is it junk?--no

RUN IT

 

Torque Plates are essential if you're trying to wring that last 2~3 percent of power from an engine and want it right away instead of waiting until the rings finally conform to the cylinders.
Torque Plate honing is the preferred way in todays engine building world but it is by no means an absolute necessity for a street driven engine.

THOUSANDS and THOUSANDS and THOUSANDS of engines have been successfully built with cylinders honed without them. THOUSANDS and THOUSANDS and THOUSANDS of those engines went on to perform perfectly and have great longevity and extremely low or no oil consumption.

IMHO, the key to building engines that have cylinders honed without Torque Plates is to use "Moly" rings and less course honing stones.
Someengine builders do the finnish hone with 400 grit sandpaper wrapped around the stones. Molybdenum (sp) material is very soft and will conform quicky to the cylinder shape.

If hard steel or chrome rings are used, they are likely to take a long, long time to seal and the oil consumption may be less than 'favorable' during this time. Sometimes chrome rings will never seal.
Moly rings are soft and will conform quickly to cylinders that aren't perfectly round or that have some taper. Some taper is almost unavoidable with standard cylinder hones run by drill motors.
A patient and skillful engine builder can minimize this but it's not normally done in a 'production' environmentas it takes a LOT od patience and time.

EACH ring pack should be fitted to the specific cylinder it will be installed in. Too MUCH end gap is HIGHLY preferrable to 'too little" end gap. IIRC it's about (.004 * Cyl Diameter)... MINIMUM.

I've seen (had) SBC engines with .030~.040 ring end gap run GREAT and with low or no oil consumption. Tha'ts out on the MAXIMUM side of ring end gap.


The oil control rings control the amount of oil that comes by the pistons when the cylinders are in "vacumn mode" such as happens on each intake stroke.
THe first and second compression rings have VERY little to do with oil control. THat's why they are called "compression rings".

Most have a "reverse twist" that causes the ring to push out against the cylinder wall with there is pressure applyed to the top of the ring, such as on the compression stroke.

The ring 'side clearance' IS a very critical parameter for the compression rings. If it's too much the ring will will "flop" back and forth or flutter and NEVER seal correctly. Side clearance is the clearance bwteeen the ring and the ring groove in the horizontal plane.

RE: Tearing down race winning engines......for those that don't know....
It's a procedure prescribed by the "Protest" rules of most racetracks whereby you (or competitor) put up a specified amount of money and your competitor has to tear his engine down for "inspection". It's a dirty, nasty job to pull an engine down "at the track". It gives your competitor the chance to see most of your engine building 'tricks' .

That's the standard way to beat the guy the next week after he just bolts the heads back on and comes back to the track to race. The 10-15 horspower that is lost due to the effect described above is usually all you need to beat him in the upcoming weeks race.

The valve stem guides can easiy be checked with the heads off the engine. You will need only a valve spring compressor and a magnetic base dial indicator. Plan on replacing the valve stem seals anyway as long as the heads are off the engine. THey are inexpensive and should be replace as a 'matter of course' while the heads are off.
Note: DO NOT under any circumstances mix the valves up when you do this.... just work on one at a time.
THis will give you a chance to clean the "backside" of the valves if there happensto be carbon buildup there. ANY buildup on the backside of the valves WILLhave a drastic adverse affect on engine power.
So clean them while you have good access to them.
Be sure and coat the valve stems with a good heavy coat of oil before re-installing the valves to reduce guide wear on engine startup.
It's hard for oil to get down by the valve stems and you do not want them to run without lubrication on engine start up.

Whew... I should write a book. LOL

 

Because this post appears to be directed toward discrediting what I have gone out of my way to share, I am compelled to reply. I have seen with my own eyes just how important torque plating is on modern small block chevy. When not using one distorts a cylinder 3-4 thousands of an inch, as witnessed by me time and time again, I fail to see how it is only optional. But then again, what do I know.

 

Pete, the shop that rebuilt my engine agrees with you. Well, at least thats what they say, and charged me a few $$ for on my bill.

I talked to the shop owner some time back, and he told me he uses torque plates on ALL engine cylinder hone work, no matter who the customer is. Street, racing, mom & pop, it doesn't matter. Well, thats what he told me anyway. I haven't had the heads off again (no reason to), so I can't verify. But I have no reason (that I know of) not to trust him.

 

For the difference in price between with and with out torque plates, i will have mine honed with torque plates and they will be checked by me after honing, before the plates come off. A out of round cylinder is just that, out of round.

But then I tend to be more than a little **** when it comes to some thing that cost me several thousand dollars and a lot of time to build.

It is just not worth what small amount of money you will save to not do this with plates.

Greg N

 

Whery informative topic indeed. Perhaps you really should write a book VetNutJim, If i hade read it perhaps I wouldent be here today
The reason my engine builder did not use a torqueplate is a missunderstanding between the two of us. We are sorting that out right now. Some way or the other I will get compensation for the "blunder" they did. But that is another topic. But as VetNutJim says he also state that the condition on my pistons is not "normal" even on a engine that have not used torqueplate while honing. Thats why we started to look on other things that might be wrong.
BUT ofcourse it COULD be a ring probleme aswell, and if that is the case we will work something out there to.

But if we leave the torqueplate and honing for a while and focus on the other possible reasons why my pistons and heads looked like they did.
Why did i have burned oil ( not carbon ) on the intake valves backside? couldent that be a sign of something is wrong with the alignment of the intake ( suckin in oil ), valve seals or valve guides. Pcv system?

If we start with the intake out of alignment theroy. Has anyone experience this, and is that a valid "theroy". Remeber that I use the converted lt1intake, that has been modifyed heavy to fit to my l98 car.
Could that lead to the oil on the intake vavles as well as the pistons?

Bad valve seals/guides. Even that I did use brand new trickflow heads its not sure they are 100%.
Could that lead to the oil on the intake vavles as well as the pistons?

Im just looking for som feedback from you that have more experince of our motors then I have. As I have to lissen to learn..

Thanks for sticking with this topic.

Devilfish..

 

i have a converted lt1 intake on my l98 and on two other sbc-1 engines--no leaks....i use the ''printo-seal'' gaskets

oil on top (inside cylinder head) of the intake valves is not acceptable and is either due to pcv valve (common), intake gaskets, or valve stem seals (worn or oversized guides can prevent seal function)

any new cylinder head (aluminum or iron) will experience some changes dimensionally during the first few heat cycles (50 cycles is usually considered sufficient to stabilize a new casting by ''experts'')....check for stem clearance with dial indicator and if ok,''hand lap'' valves lightly and look at lapping line on valve to ascertain that valve seating is correct... a good valve job on ''new'' heads that have been ''seasoned'' is highly recommended