My oil burning pig. Pics too!

-
BTW, I found this on the Hughes site on the RHS heads; not sure if this is your head exactly or not, but you can check at this link to see if all this applies: http://www.hughesengines.com/TechArticles/8laxandmaxironsmallblockheads.php


"The maximum safe lift at the valve will be about .500", like the OEM LA style heads.
anymore lift than that and the guides will need to be shortened to prevent seal damage.
These heads would use our #3806 valve stem seal. Remove the garter spring on the seals."

And your valve lift is?

And this note in the description of the Hughes seals (which sound like you Comp ones): "All valve stem seals must be installed with the protective sleeves and the proper installation tools. Failure to use the protective sleeve may result in tearing of the seal. Valve spring shims or cups should be installed before the seals are installed."
 
Mike - Thanks for the picture of your seals. I want to say I misspoke in my last post. I was thinking you were using Perfect Circle type seals which are made of Teflon (not Viton as I incorrectly said above). It's the Teflon seals which I believe have difficulty with excessive valve stem clearance since it is a relatively hard and inflexible material.

I see yours are indeed made of Viton which I understand has more flexibility. So, I don't really know that it could not handle guides with a certain amount of wear/excessive clearance.
 
Yesterday I changed oil, wemt out and pounded the snot out of it, made a few "passes" on the local "safe spot".......took a nice long ride after. Ended up putting 81 mile on it.

Came home and checked my new oil. BLACK BLACK BLACK.

Talked to my machinist today and we both agreed, it ain't guides or seals or porosity from the porting...it's gotta be the rings. He thought no way are bad guides going to allow a teaspoon of oil to pass by AND the fact that the oil is black,

Maybe when i WAS sucking oil through the valley, I glazed up the cyl walls? Maybe the gapless rings never were seated? He did not have nice things to say about gapless rings.

So...as much as it's gonna kill me, my plan is to yank it, have it re-honed with torque plates and re-ring it with CONVENTIONAL rings. Maybe even change the cam....it could be contributing due to huge overlap and late intake closing event. I bought it used cause someone didn't like it. Wonder why?

That's the plan......right now.
 
I'm having a real tough time imagining how rings can push oil up into the intake, to puddle on a closed intake. PUDDLE. Really tough.
It's got to be through the guides or around them. Got to be. Or a hole in the bottom of the plenum, if it's doing it to all of the intakes.
If the rings are bad, a leakdown test will prove it,no need to disassemble it. But if the cylinder walls are washed, it could still lie to you.So if you are not satisfied with the results of the first test, redo it it with well oiled cylinders. Just let the pressure stabilize before grabbing the number.
If the rings were leaving excessive oil on the cylinder walls, it would burn and go out the exhaust. Sure on a late closing intake angle some oil could end up in the intake with a corresponding fuel-air charge, but it get's "sucked" back, either on the next induction cycle as part of the next charge, or it goes into a different hole, shortly following as part of it's charge.
Black oil in 81 miles goes to a very fat fuel charge,and definitely speaks to rings, maybe. If your carb is fat enough to wash most of the oil off, then the rings will wear out really fast. Or if the oil scrapers are doing too good a job, then same thing. Don't blame the rings,yet. And if your carb IS that fat, it will wear out the next set just as fast.
So I would start with a leakdown test; every hole , dry then wet.
Next I would dry up the carb. I would prove the float valves are working, and that the float levels are correct. Then I would defeat the power valve circuit. And of course I would sync up the Tports, and give it the ig. timing it wants.

Since you didn't like my first two tests, here is test number 3. Pick a valve that you thought was the worst. Put it's piston to the top on it's compression stroke and remove the intake spring and seat. Leave the seal on.Clean the head surface thoroughly around the outside of the pocket. Build up a dam with modeling clay, to a height higher than the valve seal, by about a half inch. Fill the cavity with some very light oil, like sewing machine oil. Pull the valve up.Mark the level.Let it sit overnight.
 
AJ/FormS said:
I'm having a real tough time imagining how rings can push oil up into the intake, to puddle on a closed intake. PUDDLE. Really tough.
It's got to be through the guides or around them. Got to be. Or a hole in the bottom of the plenum, if it's doing it to all of the intakes.
Click to expand...
I would agree with that.

AJ/FormS said:
Since you didn't like my first two tests, here is test number 3. Pick a valve that you thought was the worst. Put it's piston to the top on it's compression stroke and remove the intake spring and seat. Leave the seal on.Clean the head surface thoroughly around the outside of the pocket. Build up a dam with modeling clay, to a height higher than the valve seal, by about a half inch. Fill the cavity with some very light oil, like sewing machine oil. Pull the valve up.Mark the level.Let it sit overnight.
Click to expand...
On the infamous BMW V8s one can pull the intake and see oil on the back of the valves. Or, one can pull the exhaust manifolds and see the trail of carbon from the valve guide right out the port where the oil burned coming out the guide past the seal. Some of those cars pass so much oil past the valve seals that just driving them in the shop would fill a 45 bay shop with smoke. Nasty. Ultimate driving machine my arse.
 
The Total Seal rings not working right is surely a possibility. But I used to completely blacken up natural petroleum oils up in 100 miles of hard racing on a couple of different type 4 cylinders, one turbo and one not with no real blow by. It was just the high heat oxidizing some components in the oil. (Reduced that hugely by going to synthetics.) I don't know how hard you hammered on it in your 81 miles or the heat in the engine or what oil you use and if it could have been effected that much. If mostly cruising, it's not likely just due to oil oxidization.

I haven't ever been able to see how bad rings would push oil up on top of the valves in this thread. But, ring blow by when you are on it hard could push oil past the seals/guides. I would suspect that more.

Sounds like it is coming apart; pretty much needed to happen at least partially to get a good read on the guides and you can put in some more appropriate rings, etc. I'd use moly top rings for their ease in seating; I'd expect your machinist would suggest that.

It would be crazy IMO to not check out the guides very thoroughly. Once a couple of springs are removed, it'll be evident.
 
Well, did a leakdown awhile ago. Ridiculously low...under 3 percent all cyls. Compression test was also weirdly "too good", if I remember it was 196 psi each cyl, not an average, they were all dead on the same. I have not done a dry/wet leakdown, but I will. I'm guessing both will yeild the same results.

So all this says is compression ring is great. What about the second ring, or the oil rings? This is why I'm confused.

And my carb is jetted the same as it was 60 horsepower ago. 78's front and back. Sure doesn't seem like excessive jet sizes for an engine well over 500 HP. And I've gone through it pretty good. I have NOT checked float valves, but have checked float level while idling. Changed powervalves to 4.5. I pull about 10 inches vacuum at idle. Timing locked at 33 degrees.

I SURE don't get how unseated rings are gonna push oil into the chamber either, but more than 1 machine shop guy has suggested it. They say they've "seen it before" with no other explanation.

I'll tell ya what. It sure seems to be using a LOT of fuel. I mean more than normal.

And the modeling clay thing...are you saying NO oil should get past the seals/guides, AJ?
 
I would be looking for No oil leakage at atmospheric pressure.Zero. And next morning if the oil level is still up, I would pump the stem back and forth, (wiggle test), in the same direction as the rocker arm points, about 700 times, and then I would pump the stem up and down about a half inch,(or until it kisses the piston) another 700 times. Ok not 700, but, IDK, say 30 or 40 times. Then pull the stem back up and check the level. It should remain pretty much exactly the same with good parts.
-Make sure the piston is at TDC, so you can't drop the valve into the cylinder.
-I remember, in the early part of the thread, reading those compression results. But I assumed that was done when fresh, and zero miles.
- 78/78 AND a PV is very odd jetting, for a combo like yours.
- if the float levels are stable,while idling, that more or less proves the float valves are OK.
-just how big is your cam, and on what LDA.
- you're not, by any chance running a too-high oil level, are you. I mean if the crank is beating up the oil, that is hard to control.
-Not to be a dick, but street motors really benefit from working advance systems, and especially including a Vcan. At part throttle, lightly loaded, and at rpms say between 1800 and 2800 rpm, a street motor often likes timing in the range of 35* to 45 *, and very often,more. You are severely limiting it, with a locked dizzy.
Furthermore, at part-throttle, and light loading ,and thus timing hampered,the engine will effectively be running retarded timing, and far short of burning efficiently, so, a significant amount of fuel will either not be burned or end up continuing to burn as it leaves the chamber, on the exhaust stroke. This is hard on headers and, you guessed it, hard on gas. And there's a real good chance , if the engine is operated this way for a long period of time, the unburned fuel will wash the cylinder walls dry of oil, and the rings won't stand that for long.
As cams go, mine is pretty small, at 230*@.050, and on a 110LDA. It was pretty easy to tune. The 292/509 was a bit harder.I ran full advance systems on both of them. Smoothed em right out.And the 230* is easy on gas.
 
So I'm sure:
You yourself doubt the possibility rings would push oil up a port in a otherwise-good running engine?
You have not measured the stem to guide clearance?
You have measured the ring sealing ability and it has passed (with flying colors) both the leakdown and cylinder to cylinder balance?
You drove it a few miles and it got oil up above the valves again?
 
I had not looked back on the compression numbers..... but 196 is pretty high with an aggressive cam. And the exact same number on each cylinder is a first, for me at least. Any chance you could borrow another one and repeat?

Just a comment on 2nd rings; many rings have a 'twist' in them; that makes them slide up the bores in a different fashion than down the bores. The 2nd ring is often setup so that it will pass over oil on the way up, and then scrape the oil going down; that's intentionally part of the oil control. Upside down 2nd rings can be a contributor to poor oil control. All compression numbers were good in your case BUT, what is often missed is that poor oil control will tend to make compression numbers look better than they really are; the oil up on the top rings helps seal them up. So, good compression numbers occasionally don't give the exact state of things, especially if there are oil control problems.

You would likely see smoke out the exhaust at SOME point in operation if ring oil control was the case. And again, how it would get up on top of the valves is not at all clear. So that goes back (again and again) to the guides and seals. BTW, often drivers cannot spot small amounts of exhaust smoke easily; it is best IME to put someone in the back seat constantly looking back while the driver goes through various engine loads.

Suggestion: why not just pull the heads at this time and really go over the guides and seals? It needs to be done anyway if the whole engine is coming out, and you might just save yourself some work and cost if the problem is just in the heads.... which seems most likely. And you'll get a good look at the cylinder walls and can see glazing, scoring, check ring ridge, etc.

Seriously, this would be my path at this point because I would be suspecting guides/seals, but I would do another compression test with another gauge first to get that info as it sets before tearing anything apart. I would also do that before letting anyone start the expense of any full teardown.
 
The rings have no idea they were manufactured by Total Seal.

I can tell you that if the cylinder bores are finnished correctly ANY ring from ANY era will seat and seal.

Also, I know the old timers (of which I can be considered one) love to slop oil on the rings and pistons, then lube the cylinder walls up real good before installing the piston. That is wrong. I know many really good engine builders who do this but it is still WRONG.

A little lube on the skirts and install the rings DRY. While rotating the engine to assemble, the rings will be 99% seated. The rings will spread the lube from the skirts around and all will be lubed.

But I don't think your issue is rings. I have used Total Seal since 1985. Never had an issue.

I have also used NOS rings from 1950 and they sealed like Jack the bear.

You have oil control issues, but rings ain't the problem.
 
well, here's my cam card. The .040 you see hand written, is how much the base circle was lowered. I HAD a lifter bore puking issue hence why the base was lowered.

What I found odd was, before Comp lowered the base my lobe separation was 110. It came back 109. Of course I degreed it and it's installed at 106.5

The first run on the dyno after Comp lowered it, my dyno guy said " this cam ain't the same". What the hell that meant I don't know. He don't talk much.

AJ, why do you think my jetting seems odd? Please elaborate, man. I value your knowledge!

I am now at the point that I would like to yank it, crate it, and ship the whole darn thing to someone and say "fix it".
 

Attachments

  • card.jpg
    28.2 KB · Views: 289
I think the issue with your jetting is when you're running a power valve you need to jet down a certain number (6-8 usually, depends on how big the PVCR is) on that side because the power valve increases the A/F ratio by that amount when it's working. So in effect when you're at WOT or at least enough to open the PV the primaries are dumping fuel as if you have #86 jets in there, and if your secondaries don't have a PV then they are running much leaner in comparison which will obviously screw up the distribution between cylinders.
 
I love how the web diagnosis has been going on for a LONG time, alot of hot air being blown around, and yet for less than $12 IN parts, you could TRY A PCV SETUP and eliminate this as a variable???? WHAT THE HELL??? So tired of people talking about things and discounting something without trying it.

Your carb is square jetted with a Power Valve???? Sorry, but that doesnt follow carb setup 101....you should have around an 8 point spread on jets front to back....

Sorry if I am sounding harsh but way too many Fu$&%%en chefs in the kitchen telling you how to cook an egg.

Try the PCV setup and get back to us.
 
redfastback said:
Try the PCV setup and get back to us.
Click to expand...
I read Ironmike to say he installed a header evacuation system. I don't know the specifics of what he did, however, that is another means of crankcase ventilation and should fit the bill. Are you thinking no? Why?
 
Yep. installed a crank evac system. One way valves welded into collectors with a nipple on the valve covers. It's working very good. Better than a PCV system, I'm sure.

Also, I have 2 powervalves. One front one rear. The HP950 comes out of the box with 6.5 pv's and 79 SQUARE jetted. If you're running 2 pv's, your jetting SHOULD be sqaure...or close. I'm sure you assumed I had no PV in the rear, Mr redfastback. Correct?

I really like all the chefs in the kitchen........somewhere along the way someone's gonna figure this out.
 
Header evac does NOT work anywhere near as well as a PCV. It is meant for very high RPM only.
 
RustyRatRod said:
Header evac does NOT work anywhere near as well as a PCV. It is meant for very high RPM only.
Click to expand...
^^^This!! Evac systems don't do anything significant or at all at idle and low engine air flows with throttle closed or lightly open, where high vacuum in the intakes will love to pull oil down past the intake seals.
 
Yep as stated a header evacuation system does not work as well as a PCV.

BTW, you're right I assumed you had only one PV.
On a street driven car, it works better to have 1 even though they come with 2. The 950 HP is designed to run WOT 95% of the time. Being that you aren't, I would change. Just my opinion. ..
 
My evacs pull 6 inches of vacuum at adle, as checked with a vac guage plugged into the dipstick tube. I thought this was pretty decent, but a PCV system pulls MORE?

I've thought about changing carbs in the past, but right now I gotta get this oil issue fixed first.

As a side note, I have no idea what carb I'd go to....this thing is a real beast at WOT, I'd hate to lose that.
 
Ironmike said:
My evacs pull 6 inches of vacuum at adle, as checked with a vac guage plugged into the dipstick tube. I thought this was pretty decent, but a PCV system pulls MORE?
Click to expand...

How much vacuum at idle testing from the timed port on the carb, or for that matter the intake? Have you tuned at all with a vacuum gauge?
 
Bad Sport said:
How much vacuum at idle testing from the timed port on the carb, or for that matter the intake? Have you tuned at all with a vacuum gauge?
Click to expand...

Bad Sport... Holley 950 HP carbs have ZERO vacuum ports... I don't think there is one for the PCV. Gotta use a spacer plate with a vacuum nipple.
 
Bad Sport... Holley 950 HP carbs have ZERO vacuum ports... I don't think there is one for the PCV. Gotta use a spacer plate with a vacuum nipple
Click to expand...

Exactly. Pulls about 10 inches vac at idle. 1 turn out, all 4 corners. Found out today, intake STILL sucking oil through the valley. Couldn't believe it...

I guess the Hughes method of intake sealing isn't exactly "perfect". Today was the 5th time I pulled that intake this season...........FINALLY I think I got it.

All the clearancing and painstaking crap you go through to build a motor, sealing a friggin intake shouldn't be a big deal. Man. Once you mill your heads, it's a crap shoot.
 

Attachments

  • leak.jpg
    50.4 KB · Views: 217
You must log in or register to reply here.
-

Back
Top