Got 514 problems!

Back in Black · #1 (**permalink**) 07-01-2006, 12:09 PM

OK, I've been gone a while but some may remember my old saga of problems with my 514.. created by my builder. It's been 4 years from heck and I'm trying to get her back on the road

It's now professionally rebuilt and dyno run, 800 miles on her with a carb and was still smoking a bit of blue oil smoke out both sidepipes when I shut her down last year and commenced to install the Holley EFI w/airdoor and rails

Went to the shop for programming and dyno, we modified a few things and got her running when the tech discovered a tab was broken in the stock distributor and it was "free advancing" and causing pinging. He stopped, we got a new distributor and modified it with a steel gear and back to the dyno

He had disconnected my PCV valve, (It went to the base of the carb/now airdoor and in street running I had little leakage last year after I installed it) he was telling me it was interfering with his tuning of the EFI computer.. he ran it up to 4 K on the dyno and the oil cap blew off sending oil onto the fender and such. The cap is just the push in type with an o ring. He tells me the engines got damage of some kind.. probably rings scorched from detonation or from being washed out from the carb. No compression tests run yet, my mechanic friend and I are going to do compression and leak down tests and inspect the plugs when I truck her back to his shop.

This mechanic friend says this sort of issue is common with this engine, especially when new, and that 800 miles is not enough to fully seat the rings..

I'm getting pro engine builders telling me the rings should be fully seated by now and this should not happen, and opposite advice from my friend..?

Any advice, comments?

Tony Radford · #2 (**permalink**) 07-01-2006, 01:23 PM

I'm not running a BB, but when my stroker was built, my rings only lasted a few minutes. I was sucking a quart of oil every hundred miles or so. It was theorized that my Demon carb washed the oil off the rings due to jetting and insufficient advance. After she failed a leak down test, my pistons were removed and re-ringed (the original rings were completely worn down). I took my car to a local dyno and they ran a bunch of pulls, rejetted the carb back to where it was when originally installed and cranked in a bunch of advance to get the A/F ratio right. That was 12K miles ago and all is well. A few other folks down this way had similar experiences.

Back in Black · #3 (**permalink**) 07-01-2006, 01:35 PM

Thing is I'm not really using much oil.. 800 miles and maybe a quarter of a quart low

Cracker · #4 (**permalink**) 07-01-2006, 02:51 PM

Don't know about the miles but after a half days worth of dyno tuning on my original rebuild my professional builder told me the rings WERE seated. Keith Craft, I believe stated the same thing after his build and tests.

Maybe George G., Bill P., Keith, Tom or some other engine experts will share thier thoughts.

Tom Wells · #5 (**permalink**) 07-01-2006, 05:51 PM

Yo BiB,

Long time no read....

Just a few off the wall thoughts:

1) valve guide clearances?
2) oil drain-back from the heads restricted?
3) vacuum leak?

Also, my Holley EFI needs all the hoses attached during tuning, especially including the PCV which seems to be a controlled and steady vacuum leak.

BTW, I finally got mine going "like a real car". I'm on the Holley wideband sensor with ECU (computer) #5 from Holley.

Still not perfect, but approaching it steadily. The latest fix was to ground the wideband controller connector separately, using its unused gauge connector's black wire. Just crossed 16K miles of smiles, including hundreds of miles on the full 3.7 mile track at Sebring last month - wide open!

Here are a couple of places to look and ask:

These guys know 385s better than anyone: http://www.460ford.com/index.php

and these guys can sometimes help with the Holley or similar EFI: http://www.chevytalk.org/threads/pos...rd=UBB12&page=
(don't let the chevytalk name bother you, there's some really good folks in there, especially street sweeper and some others - it is moderated by a Holley EFI manager)

Hope you get it going!

Tom

Back in Black · #6 (**permalink**) 07-01-2006, 06:35 PM

Tom, good to see you here.. and once again many thinks for EFI conversion info you're offered me.

#2 possibility is I think out of the picture as the oil drains nicely from the heads

#1 is a possibility that I think our bleed down test will catch?

#3 possibility.. yes, here is something to look at if we eliminate other possibilities and actually fire it up again

Thing that's bothering me is everything was good (no real oil leakage) with the PCV breather installed as before. Yes a bit of blue smoke was issuing from the sidepipes, but not too bad (I thought) My dilemma is this tech guy who is doing it is very highly recommended and seems very talented but I'm wondering that if he tuned it with the PCV disconnected then how's it going to run properly when it has to be reconnected? Won't it run leaner? He said it was running somewhat rich with the PCV removed..

PS: Great to hear you and your cobra are both well and back on the street again!

Excaliber · #7 (**permalink**) 07-01-2006, 07:39 PM

I'm a believer in a PC valve, without I worry about to much internal pressure.

A quart of oil in a thousand miles could be considered 'normal'.

Mike Simard · #8 (**permalink**) 07-01-2006, 09:04 PM

BinB, it's not unheard of for breathers to fly off during dyno runs and it may not be a problem, there will be some blowby even if the rings seal well. If you had detonation problems it's possible to have damaged a piston. Why not do a compression check to find odd cylinders? You can have a detonation damaged piston with chunks broken off around the ring land and not even know it, you would want to catch it before the ring breaks up.

FUNFER2 · #9 (**permalink**) 07-02-2006, 01:11 AM

Just do a simple "leak down test". You'll be able to see if the rings are set and if there's any blow by. Then do a compression test. Also, read your plugs.
What was the fuel curve results on the dyno ?

Back in Black · #10 (**permalink**) 07-02-2006, 09:48 AM

Quote:

Originally Posted by FUNFER2

Just do a simple "leak down test". You'll be able to see if the rings are set and if there's any blow by. Then do a compression test. Also, read your plugs.
What was the fuel curve results on the dyno ?

The fuel curve results I do not yet know, but I'll ask when they reopen on Wednesday

The Dreamer · #11 (**permalink**) 07-02-2006, 11:29 AM

Blue smoke (oil leak) out of the sidepipes could be the result of a intake gasket leak. This is especially true if you were using the Fel-Pro gaskets. Speculation of my part is people using the printoseal gasket still put RTV on them and it is causing the gasket to get too compressed. The gaskets get mangled and you get an intake leak. I switched to some Victor Reinz Nitro Seal gaskets and it cleared up my oil in the sidepipe problem.

Back in Black · #12 (**permalink**) 07-02-2006, 11:34 AM

So you're thinking the rebuilder used the end gaskets and put RTV on them, or I otherwise have an intake gasket leak due to something else? That would be way better than the alternative scenarios..

Back in Black · #13 (**permalink**) 07-03-2006, 10:22 PM

Bump!

Back in Black · #14 (**permalink**) 07-05-2006, 04:23 PM

Great news, we did a complete compression test and all cylinders are virtually identical, two pumps per cylinder made 150 PSI, more pumps much higher and still identical across the board, less than 2 PSI difference!

Plugs look a bit rich but not wet at all, no oil usage.. what I thought was slight oil smoke out the sidepipes was likely mostly slightly rich running, possibly due to the PCV valve being disconnected

Shop that was doing the work seems to be the problem.. no understanding of these large bore super stroker engines. Many people have told me these engines must have a PCV valve or they will have problems (which is why I installed it in the first place)

fordracer · #15 (**permalink**) 07-05-2006, 06:54 PM

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No offense here but I see a couple of things in this picture. The breathers on the valve covers suck. You need some open element type push in breathers.

Remember, an engine is an air pump. You have a large chamber above the piston correct? You also have a very large chamber under the piston. It's called the crankcase. A piston moving up and down is going to cause pressure in the oil pan. When you removed the PCV the pressure built to a point that it had to go somewhere. Lucky for you all it did was blow the breathers off. The PCV draws in fresh air through the breather.

Look at your everyday driver. There will always be a tube goint from one valve cover to the air inlet tube or air cleaner box. This allows the PCV to draw in as much filtered air as possible.

Back to your Cobra. If the breather is restricted the PCV will start sucking oil thus causing your slight oil burning.

Ask your mechanic friend, I am an ASE Master with an L1 Advanced

Back in Black · #16 (**permalink**) 07-05-2006, 09:22 PM

No offense taken, thanks for the advice..that's a very old picture of the original junk breathers that came on the original crate. 4 year old pics

I have billet aluminum breather/PCV valve with all an fittings/SS braided lines now.. got them from JEGs

I drove it home today across town, wonderful feeling. PCV is disconnected due to the way it was programmed (with PCV way too lean and saw white spark plugs, slightly rich with PCV but driveable) All readings look good and we changed the oil and filter just to be safe

It's going to a different shop for proper tuning before I drive it any more. I have a good lead for a fuel injection specific shop already

Back in Black · #17 (**permalink**) 07-05-2006, 09:34 PM

To clarify the PCV is run into the intake and has a high quality billet aluminum breather on the opposite valve cover to pull fresh air from

What I thought was oil smoke must have mostly been simply rich running. There's no sign of oil burning in that engine and it looks to be fine. Plugs look nice and dry

The person dynoing and programming my car was the problem.. although highly recommended by several people and seemingly a well set up shop he (The owner) apparently knew less about this specific issue than I do, which is to say not much. That's the optomistic view of his intents. I'm just going to move on and get someone to properly program my ECU so I can finally drive my machine

The shop also knocked my front bumper out of true (shoved in on one side) but that's another issue and no doubt easy to fix. I only noticed it after I got home tonight

ByronRACE · #18 (**permalink**) 07-06-2006, 04:59 PM

Sorry, but the pistons moving around in the crank case do not cause the crank case to "pump up" and build pressure. Sure, when a piston moves down the bore it displaces air...and if all 8 were moving down the bore at the same time, you'd create quite an air compressor. That would be a very stupid design, and amazingly enough...they figured this out way back in the beginning and designed around it ever since. As one piston moves down, another moves up, keeping the volume and pressure in the crank case constant. Yes, turbulent...but constant on average.

If this "pumping crankcase" theory was correct, every "sealed system" engine (just about every single engine built since 1980, probably even earlier) would blow the PCV out as well as the pan and intake gaskets, shoot oil out the front and rear seals, etc. This doesn't happen, right.

The truth of the matter is, if you're building crank case pressure, it's combustion pressure coming past the rings. Sounds scary, but every engine does this to some degree, and the larger the displacement and higher the compression, the more this will occur. Newer engines leak more as well. On a 514, a single factory style breather isn't sufficient at wide-open-throttle. One or two open element breathers (as suggested) should do the job. In addition, the more breathers you put on the crank case the better. Every time you double the area of the breather path to the crank case, you cut the velocity of the air flow out the breather in half. Air velocity is what carries the oil out of the breather.

I have a pair of -10 lines running from the valvecovers of my blown 435" bbf, and I have no crankcase pressure at WOT. It does vent some, and I do see some "fog" at fire up as well as some oil fog at WOT. The fog at fire up is steam/moisture/condensation that goes away when the engine warms. The fog at WOT is oil vapor, combustion gasses, etc..."blow-by". With just one -10 line venting the engine, I see about 1/4 psi (data logger) at wot. With two, it's zero. I keep my eye on it...it's an early warning system in the event I were to crack a ring or damage a piston.

fordracer · #19 (**permalink**) 07-11-2006, 04:46 PM

Quote:

Originally Posted by ByronRACE

Sorry, but the pistons moving around in the crank case do not cause the crank case to "pump up" and build pressure. Sure, when a piston moves down the bore it displaces air...and if all 8 were moving down the bore at the same time, you'd create quite an air compressor. That would be a very stupid design, and amazingly enough...they figured this out way back in the beginning and designed around it ever since. As one piston moves down, another moves up, keeping the volume and pressure in the crank case constant. Yes, turbulent...but constant on average.

If this "pumping crankcase" theory was correct, every "sealed system" engine (just about every single engine built since 1980, probably even earlier) would blow the PCV out as well as the pan and intake gaskets, shoot oil out the front and rear seals, etc. This doesn't happen, right.

The truth of the matter is, if you're building crank case pressure, it's combustion pressure coming past the rings. Sounds scary, but every engine does this to some degree, and the larger the displacement and higher the compression, the more this will occur. Newer engines leak more as well. On a 514, a single factory style breather isn't sufficient at wide-open-throttle. One or two open element breathers (as suggested) should do the job. In addition, the more breathers you put on the crank case the better. Every time you double the area of the breather path to the crank case, you cut the velocity of the air flow out the breather in half. Air velocity is what carries the oil out of the breather.

Then explain why when the PCV gets plugged up or totally removed oil will be blown up into the air filter?? In fact I am so positive about this I'll give you some homework.

Go out to your car and start it up. Plug the hole in the valve cover where the PCV goes. Plug the hole or holes where the breather element or tube is. Rev the car to 2500 rpm and see how long it takes to blow out every seal in the engine.

ByronRACE · #20 (**permalink**) 07-11-2006, 05:32 PM

If the crank case isn't ventilated and the PCV is the only exit path for pressure, then yes...if you block the last remaining exit path, the blow-by will pressurize the crank case to the point where it'll blow oil past the front and rear seals. If that's not a good enough vent, it will blow out the end gaskets on the intake next usually. Not the best thing to try.

Big stroker engines, high compression, or anything else that increases blow-by more than what a normal production engine sees needs a bigger ventilation system. If you want to run a PCV system, then you probably need more than one PCV valve to make a large enough exit path. And even then, keep in mind that your engine is sucking crankcase vapor containing oil...with is a very low octane fuel and induces detonation. Personally, I say forget the PCV and run an open crankcase unless the PCV is required. If you want crankcase vacuum, use a vacuum pump or a header evac system.