Long Rant oil burner

[stangbuilder]

Ok here we go this engine is 9 yrs old been rebuilt 3 times over the yrs. I drive it a lot like every where i go.. Its a 67 Shelby reso mod car with a 477 in fe made just south of 600 hp on dyno runs strong Its all alum with a Shelby block eldebrock heads reworked by ron shavers its got a fast xfi injection system on it as well.OK hears the issue it has burnt oil sense day one. AND I MEAN BURN OIL . Like 2 qts every 300 miles. You look down the intake manifold you can see oil in the intake..No brainer intake leak.Well have resealed intake over about 12 times 3 intake manifolds every gasket thats made for the fe every sealer and Technic that i know.. I have been a mechanic for over 40 years.. Hell the last sealer i tried was aircraft gear sealer thats how far i have gone.. Its crazy i have had so many people look at this and just shake their head it looks like a diesel engine on the intake ports The craziest deal is the car run perfect it doesn't smoke ether does not foul plugs. There is not one port that looks worse then other...The only thing that is common on all the tear downs .The intake gasket has oil on both sides of gasket.Side note i have taken gaskets cut corners installed and measured around the ports top bottom same not even a 001 difference its square. So heres where i am at with this.It looks to me that after a number of heat cycles it starts to pull oil between the gasket the expansion of the block and heads are different or something crazy like that. So at the end of the day i have just got to the point i just drive it and pour oil in it.OK heres my next idea i am thinking about using studs instead of bolts with a fine threaded head 

 One final side note i had Lee Parr reseal it as well... Lee Parr he was carol Shelby engine builder at the Carson facility hes done over 500 fes he shuck his head in disbelief.. He said hes never seen anything like that before.But like he said most if all his engine dont get driven like i use mine.That the best hes got...        Tim R

[cjshaker]

I assume the squareness of the intake and head surfaces have been checked? Where in the intake are you seeing the oil? In the plenum area under the carb? If it's actually in the upper intake and not in the head port I would be leaning towards a faulty PCV system or maybe even a cracked or pourus intake. Maybe the crack only shows after its heated up? That might be a tough one to actually find if it is. If the PCV seems ok, I might try a different intake just to see what happens.

It doesn't matter how much you drive it, that's not normal. It also seems odd that it's not showing up on the plugs. Are the tops of the pistons looking black/oily or the exhaust?

[machoneman]

Yeah, something in this story is amiss, not that I doubt our poster's word. Having lots of beater experience, it's almost impossible to burn that much oil and not have fouled plugs, tons of heavy smoke and oil coated piston tops, among other things. Have you had someone follow you in a chase car to see if in fact it doesn't smoke?

Also, the insides of the exhaust pipes at the exits should literally be dripping blackish oil and/or have heavily oiled inners one can wipe off with a rag for inspection.

I'd also lean towards an unshielded PCV valve, if equipped, where oil off the rockers gets directly sucked into the intake. That and a cracked intake port on the head or more likely the intake itself. Not obvious until warmed up and then the crack shows. I'd get the intake zyglo'ed or have a competent shop do so.

https://www.youtube.com/watch?v=1cl2ULh0_ss

[plovett]

You don't have dowel pins locating the intake manifold the cylinder head do you?  It's a long shot, but it happened to me.   One or two, I can't remember, of the dowel pins had been located too close to the intake port and broken through.  So, they were like a straw connecting the top of the cylinder head to the intake ports.  It burned oil like crazy until my machinist figured it out. 

Like I said just a long shot,

paulie

[ScotiaFE]

You could be flooding the heads with oil.
The Edelbrock heads with some rocker systems will flood the heads.

A test I have done is get a set of those big ugly chrome covers and cut the tops out.
Spin it up and see what's happening.
Interesting show at the very least.

And for the guy's running them. Hey they look great on your engine.

http://www.summitracing.com/int/parts/mil-85652/overview/make/ford

[stangbuilder]

Ya crazy ha. Ok i have had 3 different manifolds on this engine the last a blue tunder dual plane. I had a blue tunder 2x4 and a edlebrock as well. The 2x4 BT was the best one on the oil burning issue. I have a 0,60 restrictor under rockers push rods are non-oiling. I even went as far as to cap the cyd head oil system and put push rods that oil through them. no change.. Ok ya i need to run the smoke deal by you guys. Yes it does smoke at full throttle. If i run it down a long hill nothing i can see. Even at night in the headlights nothing..And yes you can see oil in the plenum. Now this is after it run thousands of miles.. not to the store and back . just wanted to clarify that.. Some other things are coming back to me remember its been 9 yrs dealing with this. In the 9 yrs mileage wise about 50.000 miles.

    Thanks for the reply's   

[Autoholic]

You've tried different intakes, but have you tried a different set of heads? Heads can be very difficult to inspect for any fractures that might lead to a leak. What are the common parts used over 9 years of use? You need to focus on what hasn't been changed. My first thought was your PCV setup is faulty to the extreme, if you have a PCV setup going. Even on new cars, the PCV will rout oil mist to the intake instead of letting it go to the atmosphere and result in quit a bit of oil. If this system doesn't work right, your engine will suck oil right into the intake. The best way to find out is to put a PCV oil separator on the engine. The catch can will be the tell-all. But, it seems like you haven't tried a different set of heads and a crack in the wrong place could easily turn into an oil leak right into the intake. I'm certainly not an expert on engines or the FE, but these are the two areas that came to my mind. Focus on what hasn't been changed or checked in 9 years, that's where your problem is most likely.

You think it might have something to do with the number of heat cycles. A small fracture in the wrong part of an oil passageway might not exactly leak oil when the material is cold but once it heats up and there is enough oil pressure and temperature, the oil gets through. A magflux check on the heads might show you something. The FE does have a rather interesting oil passage design to get oil to the heads, there is a small bend in it. I don't know enough about the FE sadly to know if this bend is to get around an intake port but it looks like it. A crack in this area, if there is an intake port near it, it could theoretically shoot oil right up into the intake. Finding this would be a PITA.



Can anyone tell me for sure if the bend in the oil passages to the heads are due to an intake port?

[stangbuilder]

Thank you for your reply. i have disconnected the pcv system just to check it .Yes the heads are part of the original engine its killing me to replace a 3000.00 $$$$$ set of heads.Plus on this car the engine has head studs so engine has got to come out more $$$$$..The only thing i can say for sure when you assm top end fresh. Oil consumption is less then after it run about 6 months. i know where your coming from make perfect sense .Like i said it changes as i run it x miles..Take it apart oil is between gasket . how is it getting between gasket if i am not getting a breach between manifold and gasket. Most likely i am blowing smoke up my own ass. I almost know your right .MAKES SENSE. the money is killing to test the idea..

[Mark65]

Hi, I’m most interested in this topic as I’m having almost exactly the same problems as the OP.  Engine is a stroked side oiler with ported iron heads.  Oil-saturated intake gaskets (lower halves of all eight).  Currently 202A gaskets on MR heads, 100 miles per pint, engine runs strong (200 psi compression all round).  The intake has been machined for proper fit, made no difference anyway.  I’ve tried all sorts of sealers/gaskets as recommended and it makes no difference.  Tried with and without PCV, using just breathers currently.  Smokes on high revs only.  Can see no cracks or holes in the intake ports below the oil feed passages rocker studs. 

About the only difference from the OP is that 3 plugs (1, 6 & 7) are showing oil fouling.  These are on the same side of the carb on the dual plane Performer RPM.   Most recently I changed the intake bolts for the correct Edelbrock bolts/washers and retorqued after the first heat cycle.  Previous washers were not hardened.  No difference.

I have not tried replacing manifold or heads yet.

Maybe the heads need crack testing/replacing?

[machoneman]

As to maybe flooding the heads with too much oil (any restrictors in place? Using the OEM tins under the rocker stands? Unblocked oil drain at the rear of each heads? Have you checked the oil level in the heads with cut-up valve covers?) one should see lots of black gunk (oil and gas) on the backsides of the intake valves. Is this present? It's unlikely you have a cracked head as having 3 cylinders on different sides fouling plugs  makes this very odd.

As previously mentioned, is the OEM steel pin present in the front china wall of the block, holding up the intake manifold from seating properly? 

http://www.network54.com/Forum/74182/thread/1310624374
 

[Mark65]

There is definitely black goo on the backs of the intake valves.  Oil feeds to the heads have restrictors fitted.  The pin is on the front wall but I've ground it down some way and it's not holding the manifold up.  There are no tins under the rocker stands but the return paths for the oil have been smoothed out to help presumably.  I understand that many people don't use them anyway.  I haven't checked for oil pooling but I don't believe that's a problem although I may be able to check somehow (I don't have any spare covers to cut up).

Thanks

[Katz427]

We (a friends 408 windsor) in the drag car, it does see some street. Looked at all those things. We always found oil in th PCV hose. Oil separator for the PCV (helped), gaskets, checked the valve guides (again) a couple intakes on the loose side of spec. No real problem cruising only when pushing it hard. Showed good compression, good leak down, ran strong mid 11's. Finally taking things apart I decided to really look close at the ring lands. Upon a close inspection 3 of the pistons ring lands have a wavy surface appearance looking under magnification. Two pistons showed this on the middle ring land. The other one had an oil ring groove with some problems. He is going to put new pistons in it for next seson, touch hone and rering. The 3 cylinders with the suspect pistons were the ones that were showing the oil. The MSD fired the plugs thou they were black in those cylinders. FWIW the pistons were part of a relatively cheap stroker kit.

[Joe-JDC]

What seals do you have on the valve stems?  If you still have the teflon style, they can be the problem.  If your guides are worn, or have/had too much clearance from the start, you are sucking oil past the guides and it will show up in all the intake passages.  The intake valves can be run as tight as .001" with some of the newer guides and not seize up.  Use Viton seals on refresh.  Just a thought.  Joe-JDC

[Mark65]

Joe, it's got Viton seals and it had new guides maybe 3000 miles ago.  The heads were checked over at the time.  No smoke on start up from cold.

[My427stang]

These seems  very simple recommendations, but:

1 - Have you verified that all/some of your intake bolts are not too long?

Almost every FE manifold uses different bolts and I keep a box of the ones I take out just because every swap I do seems to like something different.  Generally, on the bench, drop the bolts through with the washers you'll run and 1/2 inch of thread showing is generally good.  However, best is to measure the depth of the intake bolt holes because you don't want them too short and pulling out either

2 - Have you verified that the intake isn't hitting the head gasket tabs or the block?

I haven't seen it often, but I have had to take an angle grinder to bevel a 45 degree-ish cut along the length of each side of the intake.  It can hit the head gasket tabs, and I haven't seen it, but theoretically could hit the block before it compressed the gaskets