Oil consumption on Windsor stroker

I've got an AC Cobra replica and recently had my stock-stroke 351 replaced with a 427 Windsor stroker with:

- Reworked Windsor block
- Scat forged stroker crank
- Scat lightweight H beam rods
- Keith Black pistons with ET Molly rings (filed to fit)
- Elgin solid cam, split duration
- Stage III ported and polished TFS Trick Flow heads with billet aluminum roller rockers
- Port-matched Vic. Jr. intake
- Barry Grant 750 Might Demon carb
- Canton pan with windage tray
- Aluminum flywheel
- ARP fasteners through out
- Everything is of course ballanced and blueprinted

My question, since I've got almost 2K miles on the new engine and she's still drinking oil (qt/100 miles), is there any hope that the rings will eventually seat? She starts, runs and idles great, pulls smoothly and strong through 6,500 RPMs and doesn't smoke. She doesn't leak. The builder is prepared to pull the motor and go back through it, making any necessary mods, but it kills me to think about going through all that as driving season is coming fast. Any similar experiences that had happy endings?


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Streets, good point. My previous stock-stroke Windsor was blue printed. I guess MY point is that the motor was not simply "bolted together", but gone through pretty thoroughly, bearings plastigauged, rings filed to fit, rolling assembly ballanced etc. Anything to contribute on the problem?

:CRY: A quart to 100 miles after a 2k break in is probably not going to heal itself Tony. It's time to bite the bullet, there's too much $ in this engine to mickey mouse it. I'll play "master of the obvious" here and say there's something wrong in there.

Streets; Do you run a differant oil to break the engine in? Now I don't know if I've been doing this right? don't chew me out. But I was told to run a non detergent oil to break in the engine. And then after that to run a high detergent oil. Is this right?I was told that this allows the engine to work it's self in to a good grove or allowed enough wear to beak the engine in, you know rings,cam,ect. I was then told that if you ran a high detergent oil from the beggining that the engine might never break in right and would use oil because of the rings won't seat or wear in properly. What is your thoughts on this, I'm just asking so please don't get mad at me for being a little Dumb,about this. What would you do to break in your new motors?


Vegas

Streets; Sounds good to me, well I guess I've been doing it right,minus the engine stand to run it on. thanks


Vegas :LOL: :LOL: :D :LOL: :LOL:

Guys, I pulled the plugs yesterday and they look clean (tan and dry), no signs of oil. Would you expect this from an engine that was burning a qt/100 miles? I will be scheduling a tear down with my engine builder early next week. But we're all a bit perplexed. It HAS to be burning it. There is a sooty residue at the exhause openings of my sidepipes, but the car doesn't smoke or hesitate. It runs smooth and idles fine. Does this make sense?

Tony Let me throw my 2 cents in. If during the engine rebuild, if the clyinders were bored you might have honing residue that has clogged the oil return holes. If they are clogged, oil cannot drain back into the crankcase. If this happens, it can accumulate in the cylinder head and over lubricate the valve stems causing oil consumption. When you say you can't see it smoke, do you mean just on start up?

When I first start up or when I really nail it, I get a puff of smoke from the pipes, but when I'm driving, nothing. Since I'm running a solid cam, the valve covers have been off a couple of times. Nothing out of the ordinary.

I had emailed the Keith Black tech line a couple of days ago. Their response was that since my plugs are clean, it is highly unlikely that there is any problem with my pistons or rings, the problem is likely in my PCV valve. That could make a lot of sense. Though I'm running the same TFS heads I had before, they are now outfitted with billet aluminum roller rockers and new valve covers. Maybe the PCV baffle was damaged. I have noticed that the oil consumption is particularly significant after I've pushed the engine hard RPM-wise. I assume the negative pressure at the output of the valve is increased with RPMs. In any event, it will be easy to check tonight when I get home. I have my fingers crossed as this would be the best possible scenario.

Streets Centavos? Guide Seals? Ya your probaly right but I just threw in my 2 cents worth since I did have that problem one time.

streets I have never done a bore on any block myself but have watched many being done. What you state is correct except I have never seen the block soaked in oil before. What I posted to tony is a bad boring job a friend of mine received. The cylinders were never cleaned out except for a quick rinse with soap and water. You can imagine what the cylinders looked like after just a 1000 miles on it.About a quart every 100 miles.

streets Many thanks for info. It makes sense. One of these days I'm going to due a bore on a block myself and use the tank of oil like you suggested. I welded the crack in my flathead and sleeved it. Didn't work so I'm going to have new sleeves put in and have it bored .060. Hopefully as I said this would be my first bore job. Need to ask you a question. On a previous post you mentioned(I think) that you had a replacement knee. I've got to have it done pretty soon and was wondering how the knee felt afterwards?

Well, we thought we had it. The engine makes so much vacuum through the PCV valve, it looked like it had to be sucking oil into the intake. We plugged the line with a restrictor, but it's still consuming oil like crazy. Again, plugs are clean and pipes are sooty.

Tony, that thing with the clean plugs is a puzzler ain't it?

What kind of oil are you using, synthetic or mineral? What viscosity?

I'm assuming you've done the logical inspection of the underside to see whether or not it's got a coating of oil on it.

Bob, it ain't leaking. When I emailed Keith Black (those are the pistons I'm running) they said that clean plugs indicates the oil is coming in through the carb/intake. Today, I purchased a plug for the vacuum port on the carb and a breather cap to replace the PCV valve. That will at least eliminate one potential culprit. The pisser is that one of my buddies here has basically the same engine and he doesn't use any oil. I'm wondering if all the porting that was done on my intake and heads is creating too much vacuum. I'm running a Vic. Jr and a Mighty Demon BG carb. I'm running out of ideas. Pretty much everyone is stumped. Worst case is to pull the motor and start all over again. It's all polished and dressed out for show. I hate the thought of it having to be taken back apart.

I had another reason in mind when asking about the oil, not just leaking.

I've been running Valvoline 20W50 since the engine was installed at the recommendation of the builder. I know that synthetics can prolong the pre-break in period. I still don't get the underside coating comment (I'm a bit slow in the reading comprehension area).

:LOL: That was in reference to leaks, which you already answered, so give yourself more credit. The 20w50 mineral oil kills my other thought. If that were blowing by it would show on the plugs.

Has your builder done a leak down test?

Tony, this is strange enough to make me curious :)

Just my 1-3/4 cents... if your plugs are tan and you’re not seeing a lot of smoke (1 quart per 100 miles would generate noticeable smoke), you’re probably not pulling oil through the cylinders and burning it (through the intake or otherwise). You’ve got to be losing the oil on the exhaust valve side. Sounds like bad valve guide seals or clearance problems on the exhaust side. You said that the pipes were sooty… are both sides equally sooty?

Dan J

Dan, both sides look about the same. Since I burn around 12-15 gallons of gas per 100 miles, a qt of oil in 15 gallons doesn't seem so dense if it's mixed with the fuel and air prior to combustion. Even though my TFS heads had 8,000 miles on them (on my previous engine), they received additional porting, new valve guides and seals, a valve job and new roller rockers. I doubt there is anything wrong in the heads. I will be able to put that theory to rest this weekend when I replace the PCV valve with a breather. This motor's so shiny, I can see a leak from a mile away.

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Tony, beautiful engine! I just love a good mystery :) I hope that you are correct, and that no teardown is required in order to fix the problem. Please let us know if the PVC valve does the fix.

Dan J

Thanks Dan. Will do.

what kind of condition is your intake manifold in and how well is it seated? i had a similar problem with a 302, ended up that my intake manifold had small cracks in it enough to let oil into the cylinders... the reason it only happens on startup and higher RPMs could easily have to do with your oil pump, pumping harder when its at those higher RPMs... the only way i found out that this was the problem on my engine though was that my oil pressure was slowly rising from 60psi to about 120psi in about an hour, which was because water from the radiator was leaking through those cracks as well, but its not always gonna be what happens depending on where the cracks are....

also too much chrome for my liking.... chrome brings engine temp up, and i like to keep mine as cool as possible

thesals, I really don't think it's the intake. It was new when installed. It was hand ported and polished prior to assembly. There isn't any chrome on my motor, just polishing. My engine temp runs at the bottom end of the temp spectrum at all times (160 degrees). I'm running a Griffin aluminum radiator with two 9" pusher fans and a SPAL 16" puller all on a thermostat and Edelbrock high volume water pump. Temp has never been an issue for me.

Incidentally, the saga continues. I removed the PCV valve and did some pretty hard cruising over the weekend. After the ride, I was still further down on the dipstick than I should have been. I also replaced the plugs while marked the old ones for my engine builder to analyze. Though they look good at the electrodes, there is a fair amount of black gunk down in the grooves at the base. A couple of them are particularly gunky compared to the others. I know I'm running a bit rich on my 750 DP Mighty Demon carb, so that could be a contributor. I jacked the car up and spent a couple of hours underneath with shop rags and a can of degreaser. I had significant build up from a leaky rear main seal in my last engine. I got everything shiny and re-inspected it after the test run. No oil leaks anywhere on the engine. After I had a few hundred miles on the engine, I replaced the 20W50, but accidentally purchased the Valvoline Max Life as opposed to the racing formula I normally use. I've wondered ever since if there is anything like a Slick50 additive in Max Life that could have left a low-friction surface on my cylinder walls therefore prohibiting break in. Since I'm running a remote oil filter adapter and external oil cooler, I never get all of the oil out of the system when I replace it. I feel like it's got to be due to the rings not seating.

Streets, sounds easy enough. I'll be scheduling a return trip to my builder's shop tomorrow.

TONY, I had a good 357w in my last hot rod and it burnt oil for over 4000 miles, sold the car (to build a new one) the guy ran it for another 1000 miles or so and the oil problem went away, ur guess is as good as mine to what was wrong........

20w50 might be heavy for a new engine.

JOEE, when I hear yours and similar stories, I gain a sense of relief that there is still hope (other than a removal and break down). I keep saying I'll go another few hundred miles. I guess I'm good for a few more.

There are so many others in my area running similar strokers and they all use 20W50 per the advise of the builder. I seem to be the only one experiencing this prolonged problem. Most of the guys seem to see a virtual end to consumption in 1,000 or so miles. It runs so well, I just hate to mess with it.

Quote:

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Originally posted by Tony Radford
It runs so well, I just hate to mess with it.

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I wonder if it might be your valve cover leaking out the back next to the fire wall and directly unto your exhaust? I'm having a simular problem. It is frustrating.

There aren't any engine leaks. I've thoroughly cleaned the underside of the car including the engine compartment, run the engine gard and reinspected for leaks. So far, no leaks.

Do a compression check like Streets said. Might want to do a leak down check on the motor, it will tell you what the rings, guides, and valves are doing.

Tony Radford

Bad rings or a bad honing job might comprise 1% of all oil burning problems after a rebuild. I thought of another probable cause.

Do any of your rocker studs end in your intake runners?? If so, you might want to run some thread sealant in their threads and try that.

I'm not sure about the rocker studs. I do know they were replaced during the build which included new studs. Since removing the PCV valve didn't help, I'm back to believing the rings are taking their time to seat (at least I hope that's it). If things don't appear to be improving during the next few hundred miles, I'll go in for a tear down.

I am guessing rocker studs, intake gasket, or valve guides. I would check them in that order, for that would trying the least expensive fix first.