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Gmac454
04-04-2005, 10:41 PM
I have a 350 4bolt .30 over (355) all the standard stuff, 2.02 heads, rollers
10.4 - 1 comp. edelbrock airgap intake, etc... it runs perfect and i only have about 50 miles on it. still trying to break it in. my problem is that i blow oil out of the pcv valve hole and out of the front seal on the timing cover. what can i do to stop this? i have put a larger pcv valve on it and a new larger breather on the passenger valve cover. still when i start driving it i start dripping out of the timing cover harmonic balancer seal. and down the sides of the valve covers from the rubber grommets for the pcv and breather.

Thanks :(
Gmac454

MaxHarvard
04-05-2005, 07:51 AM
Sounds like some massive blow by.

is your PCV connected to a strong vacuum line? you'll need it!

Y-TRY
04-05-2005, 06:19 PM
I agree with Max. are the rings new and with a fresh bore hone? Sounds like all of your compression is sneaking right by your rings and into the crankcase.

Gmac454
04-05-2005, 10:46 PM
the block is newly bored and decked and trued. the pistons are new as are the rings. it only has about 40 miles on it. but i have never had this much crank pressure ever. I was hoping the rings would seat after i put a few miles on it. do you think if i did a compression test it would give me an indication of what is up. you know do a dry pump and then poor some oil on the seal the rings and do a wet pump ??? what do you think. i appreciate you guys mulling this over thanks!

camcojb
04-06-2005, 10:16 AM
The other thought is that if you don't have baffles under the pcv and breather areas they will drip oil period. Also the front pan to timing cover area is an oil leak area.

A leakdown test would be best to determine what condition the engine and ring/valve seal is in.

Jody

JohnM69SS
04-06-2005, 03:52 PM
Agreed. Just curious, do you have an oil pressure gauge on it? If so, what PSI when it is warmed up? Was the crank ground during the rebuild? I know that and tighter tolerances make for higher oil pressure, but this sounds extreme.

Also, what year 350? Sometimes, if you do not trim the tabs off of the edges of the rubber gasket that slips into the lip of the bottom of the timing chain cover, they can bind when the oil pan is bolted on, or if the timing chain cover was removed and replaced without removing the oil pan.

XcYZ
04-06-2005, 06:56 PM
I agree with Jody about the baffles, and how about the timing cover, is it chrome?

Gmac454
04-06-2005, 09:12 PM
ahh yes the timing cover is chrome,
I had a 2 piece on their originally and it leaked like a sive so i trashed it and replaced it with a single piece steel unit, and i replaced the seal in case i ripped it putting in the harmonic balancer. The harmonic balancer does have a sleave on it because it was so worn. i wonder if that is not allowing a good seal.
I have baffles on the pcv and breather,
The crank was totally reground and polished,
I am running about 60 psi for oil pressure, and that is with a mechanical line gauge not electric. The Block is a 70-74 vintage 4 bolt main.
The thing is, i am pushing oil out of the harmonic balancer seal, not the lower oil seal to the front lip of the pan, that usually leaks if you dont put a dab of permatex in the corners. you know what i mean. it is pushing out of the seal around the dampener...
I get no burning oil so i am not leakng past the rings into the chamber, and the motor doesnt run that hot, 200 to 220 with a stock 2 core steel radiator. so it doesn't seam like i am getting hot gases pushed back into any other area's. It just doesn't seam like rings are leaking by, although i cannot toss out that suggestion it is surely possible. I am about to yank the motor out and tear it down, replace the rings, the harmonic balancer with a new fluid dampner, and new seals and gaskets everywhere. doesnt sound fun...but i am running out of idea's

XcYZ
04-06-2005, 09:57 PM
Gmac, I just noticed you're in Minnesota. Where abouts are you?

Gmac454
04-06-2005, 10:14 PM
im in hutchinson, straight west of the metro about 45 minutes from minnetonka on highway 7. Man your car is totally sweet. i was just reading all your stuff, that is so sweet i have to see the twin turbo motor! Are there any cruise nights or car meets that go on? there is usually a meet and greet in hutch every friday night, but that is about it.

XcYZ
04-07-2005, 07:40 AM
My car won't be on the road this summer. There's still quite a bit of stuff to do and I'm trying to make a decision on the front suspension.

Are you going to Car Craft? Will your car be there?

ohcbird
04-09-2005, 02:36 AM
You didn't overfill it, did you? Where is your pcv hooked up to?

Is your balancer new? Sometimes they get a groove worn in them under the old seal lip. They make 'seal saver' kits for this, but I'd get a new balancer.