[461-69bird]

Would this cause any breathing issues by putting extra pressure into the crank case?

My engine builder has stripped down the motor to find the problem with it pushing oil out the dipstick. It did what I told him was happening on his dyno, got to 3000rpm and pushed oil out. He says that all the bores and rings are perfect and measure correctly. He did his own leakdown test before and got 15% on 3, 12% on 4 and 7 the rest were 9%.

I had the same set up with my solid roller cam and that had some leaks around the pan but nothing from the dipstick.

Could the lack of holes in the poured in brace be restricting the breathing?

[Formulas]

there is still the hole in the front of the block by front cam bearing.. pressure under piston can travel through timing cover and vent to lifter valley .... is there no way for valley oil to drain back down from top of lifters with the pour? since block is tilted back could be alot of trapped puddled oil there making it hard to get consistant level readings... i cant tell from picture

[steve25]

You need to repost that picture because we can't openit up bigger, but non the less if that valley is now fully sealed and was not before, then yes that is why your pushing oil and dip sticks out.

If that valley is now mostly sealed a header evac system will not work so you need to run a vacuum pump or drill and put vent tubes in there like they with BBC motors.

I am really questioning that builder and his thinking / guidance now after seeing this.

[461-69bird]

The brace was done on the last build by Len Caverly.

[461-69bird]

Steve, how and where are those tubes fitted?

[Dave Polichena]

461, the valley would have to be drilled and tapped for the tubes. 1/4 pipe and stand up them straight up

[461-69bird]

Thanks Dave, do you think they would help or are needed?

[chuckies76ta]

So this is why the oil is blowing out the dipstick. Makes sense now. Pressure in the crank case has to go somewhere.
https://forums.maxperformanceinc.com...d.php?t=871548

[steve25]

What does the OP exactly mean by “ he did his own leak down test before “?
Is before in reference to before this time on the dyno to prove out the dip stick issue, or before the motor was first put in the car?

This Seems to all have been discussed before in a previous post that you made, but to me that 15% leakage even on a fresh bore and unseated rings is high regardless of the builder saying that everything measures fine.

[461-69bird]

Steve, yes he did a leakdown test before running it up to 3000 to see for himself if it came out the dipstick, which it did.

Chuck, do you think that brace is the cause? It's the same set up as when I ran the solid roller when it was built originally by Len and Shaker. It always leaked from the pan gasket before, but perhaps the rings sealed better when they built it than now on this rebuild.

If that's part of the problem, short of removing the epoxy or drilling vent holes, would putting a breather where the valley pan pcv grommet is, relieve some pressure? It's currently plugged as I'm not running a pcv.

[Formulas]

Observation... a lower HP/torque engine with a leakdown rate of 5% will dump less volume in the crankcase than a higher HP/torque engine at 5% leak rate

above rings cylinder pressure is greater with more HP 5% of 1000psi is a greater volume than 5% of 100psi

your oil pan only leaking before could of been a tell now magnified with more power now blowing out of dipstick

Also with aluminum heads there is less room for crankcase venting to valve covers due to fewer voids / holes in the pushrod areas compaired to old iron

something i would do if my dipstick was blowing out, i woul back total timing off say 4 degrees to make sure i wasnt over advancing with a new build

[steve25]

The motor has no place for the crankcase pressure to go with no PCV.

Besides that part of a stock system which only works when there is enough vacuum the factory set up had a breather tube off of one valve cover that was plumbed to the air cleaner and that vacuum source would then take over once the PCV no longer worked .

[461-69bird]

Formulas, my current set up and problem is lower hp and tq than before. 542hp 581tq now against 620hp 601tq.

Total timing is the same at 34 so do you think setting it at 30 will help?

[Stan Weiss]

Originally Posted by 461-69bird

Formulas, my current set up and problem is lower hp and tq than before. 542hp 581tq now against 620hp 601tq.

Total timing is the same at 34 so do you think setting it at 30 will help?

Do you have dyno sheets from both engines?

Stan

[461-69bird]

Steve, so having an open breather on each valve cover wouldn't do the same thing? My issue is at 3000rpm and high vacuum around 12"

[461-69bird]

Stan, they are both in these threads

https://forums.maxperformanceinc.com...d.php?t=802656


https://forums.maxperformanceinc.com...d.php?t=870038

[Dave Polichena]

Originally Posted by 461-69bird

Thanks Dave, do you think they would help or are needed?

This could help a bunch, the crankcase needs to get vacuum. Your current set up is not allowing enough area to pull from the top, especially with header evac. Your limited real estate up top is your crutch. Fix that and you may get better ring seal too.

[shaker455]

Hi Rick,
I saw your post and asked Lenny to look as well.
In short he said the brace will not cause pressure.

Before that I was thinking if you use an electric fuel pump and if it was the case with pressure,
You can try using the fuel pump mount on timing cover as a vent, I've seen some pretty tall chimneys people built in the past.
Jeff

[461-69bird]

Thanks Jeff, I tried messaging Lenny to ask his thoughts, good to know. How would I do the fuel pump mod?

[shaker455]

He is not on here often but I hope he chimes in as he did one of those set ups for his current Gasser.
Hole in block off plate with welded tube or pipe threaded elbow.
On his I think he has a hose up into fender well.
Long time ago I saw a pic of one J-shaped. Tube pretty high with a breather type bird house on top.
I'll look for a pic later today.