bad oil leak at high rpms

[Stangtamer]

hey whats up to all...i've got a 331 stroker with a 7 quart moroso pan on it...it leaks like i've never seen at high rpms...i took it to get tuned yesterday and when it was on the dyno, it started spewing out oil everywhere on the floor...it gets all over my clutch cable and long tubes and it sucks!!! i've checked under the car, replaced the dipstick tube, put teflon tape on it and silicone and i thought that fixed it...no i was wrong...i know that my rear main is leaking a little, but when it flings out of the side of the pan, i know it is something else... anyhow, i've tried putting silicone on the two bolts before the back bolt on the pan cause there are drips coming off of them and it still leaks... how could it be pouring out a puddle about five inches in diameter at high rpms...any suggestions would be appreciated a lot!

-jeremy

 

[04sleeper]

Jeremy,

You need to degrease the entire underside of the engine and pinpoint where the leak is originating from.

Then you can get a better understanding where it comming from and how to fix it.

 

[Stangtamer]

thanks for the advice...i degreased part of it when i put the silicone in the bolt holes, but i never thought of doing the whole thing...i'll try it...is there any place in the head where oil could be coming out of...i don't think there is but im just now learning about ford motors so i don't know...its pretty mysterious and im trying to solve it...let me know if you have any more suggestions...thanks again!
-jeremy

 

[04sleeper]

Well if you have a leak from the valve covers then I would consider that a leak from the head.

Also another place to check is the back of the intake. The rear seal on it as well as the PCV valve and screen. These are sometimes mistaken for a rear main seal because they could cause oil to run down the back of the engine.

With the 331 be sure to ventilate your crankcase pressure somehow. Make sure you don't have the valve cover vent tube blocked off or at least have a breather to help ventilate the crankcase pressure.

If not the pressure will try to escape other places, usually by the gaskets and seals.

 

[PurpleStripes]

Crankcase pressure increases with rpm. A bad or ill operating PCV system will cause severe leaks as the pressure increases. I would replace the PCV valve, the small steel wool screen that sits below it and clean all pcv tubing and ports.

 

[HISSIN50]

Are you burning any oil? I think Kevin (and PS) is/are onto something with the PCV. A catch can, breathers, etc might help out.

Good luck.

 

[Stangtamer]

im running a victor efi intake and it has no pcv screen at the back...the valve covers are dry, but i do have a pcv valve in the valve cover and a breather on the other...should i put a pcv valve on the one with the breather as well? it would be nice if the problem is that simple...i appreciate the advice...i think it might get me somewhere...thanks...oh yeah, i am burning oil...i don't know if its the fact that its a stroker, or the rings...they are plasma moly...i used perfect circle rings but broke some second groove rings due to the fact i had to size them and they are brittle...i had to get more rings but the perfect circles were much too expensive, so i got some sealed power rings of the same material...my auto teacher at the college i built this at said i would be fine...have any of you had any luck with plasma molys? any more suggestions with this information?

-jeremy

 

[04sleeper]

Jeremy,

I had a little solid roller 306 with a carb I had built for me and it took a PCV valve in the back of 1 valve cover and a breather in the front. And on the other valve cover 2 more breathers to keep oil from leaking out of them.

Remember when putting in breathers to be sure to put in oil baffles.

 

[eighty8]

I am running a Moroso 7 quart oil pan I have had the pan off twice trying to fix my oil leak (Silverado Syndrome). I have 2 friends both Master Ford techs that helped me. I think and I may be wrong that since the oil pan is right up against the trans that it causes the pan to leak. My one friend that is a master ford tech has a 86 with a S/C 306 bought a Milodon Oil pan it is not up against the trans like my Moroso is. My oil pan is going to come off and get resealed for the third time soon to cure the Silveraldo Syndrome. If this doesn't fix the problem I will pitch this POS Moroso in the dumpster and buy a Canton or Mildon pan like my friend has in his car. Anyway this is just my 2 cents...

 

[Stangtamer]

i think i'll pull the motor and put the stock pan on it...i don't need 7 quarts for daily driving...moroso sucks! its nice to know im not the only one out there with this problem...

 

[mfewtrail]

Have you taken a peak behind the intake plenum and looked at the lower intake area at the back of the motor to see if it's dry? You should be able to see down there from the drivers side of the car if you get close to the firewall while looking.

 

[HISSIN50]

i think i'll pull the motor and put the stock pan on it...i don't need 7 quarts for daily driving...moroso sucks! its nice to know im not the only one out there with this problem...

Do you have a high volume oil pump? If so, there is no guarantee that it wont suck the stock pan dry (there is great debate on this, but I would not want to chance it myself).

Good luck bud.

 

[Stangtamer]

the intake is dry in back and i am running a stock oil pump

 

[87mustang347]

damn, thats really weird. i just noticed a huge puddle today too under my car rite at the drain plug. i also have a moroso oil pan. o yah and that smoking problem that i told u guys about was because the plug that i used to plug up where the dip stick goes came out, so oil was spitting out and onto my header which caused the smoke. well any ways, my car never left a puddle this big, even when i didnt have the dipstick in there. now i put it in, took my car out for a drive, parked it to moe my lawn and as i walked to it to put it in the garage, i saw a puddle under neath it. damn, these pans really do suck!

 

[mr.b]

sounds like pcv problems. you are building a lot of crankcase pressure and it has to go somewhere.

 

[Stangtamer]

yeah, i definitely should have stuck with stock a while back, i put a fraction of the old dipstick tube in the old dipstick hole along with some silicone, but maybe thats not enough...do you also burn oil? mine burns some, especially at high rpms...my oil leak is definitely from crankcase pressure cause it was spraying out on the dyno...it definitely had some pressure behind it, but only at high rpms...is there any way that my cylinder heads are not sealing well enough to allow pressure to come back down in the crankcase? that might not allow my rings to seat either...when i compression test is, i get anywhere from 110-150 on different cylinders...somethings not completely seating...any thought would be appreciated...kill moroso

-jeremy

 

[Stangtamer]

i have a pcv on on side of the valve cover going to the intake and it does work...i checked it...i have a breather on the other side cover...should i get another pcv in place of the breather? does that matter?

 

[87mustang347]

yeah, i definitely should have stuck with stock a while back, i put a fraction of the old dipstick tube in the old dipstick hole along with some silicone, but maybe thats not enough...do you also burn oil? mine burns some, especially at high rpms...my oil leak is definitely from crankcase pressure cause it was spraying out on the dyno...it definitely had some pressure behind it, but only at high rpms...is there any way that my cylinder heads are not sealing well enough to allow pressure to come back down in the crankcase? that might not allow my rings to seat either...when i compression test is, i get anywhere from 110-150 on different cylinders...somethings not completely seating...any thought would be appreciated...kill moroso

-jeremy

dude! something is deffinetly wrong. compression is supposed to stay alot closer together then that. i just did mine yesterday and it was 180 across the board except for the #1 & 2 cylinders. 170 and 175

 

[Stangtamer]

so what do you think the issue is...i bought my cylinder heads used with 400 miles on them...supposedly...they had so much port and polish work done and i got the for $900 and they aluminum holley systemax heads...so it was almost too good to be true...considering i just build this motor and it has plasma moly rings...its there a chance that the heads are not sealing up completely which is not allowing to rings to seat either? cause i do burn a little oil...more at high rpms...what do you think...im gonna take the heads off and have them evaluated...maybe they are not completely sealing...what do you think?

-jeremy

 

[D347643]

dude i got it, same thing happened with me! might sound dumb but did you plug up your existing dipstick tube hole in the block@!??