She ain't happy with me. Spitting oil out.

[usar17]

Well as some of you know my 85 k10 hasn't been the easiest rebuild. Especially with not having access to a good amount of tools.

History:
has a 305 in it. Rings are most likely shot. No crankcase ventilation, as in i have positive pressure at the breather instead of negative. good vacuum at PCV valve. Took breather off that goes to air filter bc it was slowly saturating the filter with splash up. replaced it with a push in breather filter.

pulled the valve covers off to clean them up and clean out the baffles and check for clogged vent holes in the heads. First re-install attempt was with rubber gasket, valve covers leaked. second attempt was cork. passenger side still leaked. third attempt was cork and RTV. worked.

turned my attention to maybe making this engine last a little longer till i could save up my money to purchase and put in a 350 my friend has. added a can of Restore engine restorer and lubricant. can said it helps reduce blow by and i thought that may help gain vacuum in the crankcase. Ran great for a little bit, more throttle response, seem to be working good.

Restore
http://www.autozone.com/autozone/accessories/Restore-19-oz-8-cyl-engine-restorer-and-lubricant/_/N-4b63?itemIdentifier=521229_0_0_

Preset:
she's leaking oil bad all over the passenger side valve covers. it's not a bad seal because its coming up and out of the filler neck too. oil pressure gauge isn't reading any higher then normal, roughly 35-40. but i have a major oil evacuation happening. Driving it just causes a ton of bluish grey smoke from the engine compartment. I can see it dropping down at idle and burning off the exhaust manifold. The frame, front driveshaft, starter, and transmission are covered in oil now.


any thoughts? or is she done?

 

[89Suburban]

Sounds whooped. Try to seal the leak wherever it is and run some thicker oil and take it easy on it. Compression test will shed some light for sure. Is your buddy's 350 ready to go or do you have to rebuild it?

 

[usar17]

the 350 is in an 87 k20 still. I want to pull it to a stand so i can clean it up and paint it. It was recently rebuilt by GM with only 3000 miles on it. I also want to switch the intake so i can run it carberated. I don't feel like running all the wires and sensors for TBI. and i'm not in the best financial situation to complete all this anytime soon. That motor probably wont be mine and ready till spring.

That's why i'm asking about any temp fixes to help the current motor. It's just blowing oil and pressure on the passenger side. I can't seal the fill cap closed. Would changing the oil to thicker help create some crankcase vacuum to balance the system? The last time i actually drove it i blew out a quart of oil in 10 minutes.

 

[skysurfer]

I had a rebuilt 7.3 diesel in a delivery truck doing the same thing, it was building pressure in the top end and leaking oil like mad. On that engine there was a 1.5" diameter tube coming off the top of the engine that was for adding oil. I removed the cap and installed about three feet of heavy-duty rubber hose, ending just below the pan. It was basically a down-draft tube and vented all the pressure from the top end. No oil came out, just vapor. I ran it that way for years.

If you did something similar and vented both valve covers it won't leak past the seals anymore. Of course it won't fly if you have emissions testing, down-draft tubes were banned about fifty years ago.

 

[usar17]

To my knowledge downdraft tubes are a diesel thing.... I've only ever seen them used in that aspect.

 

[skysurfer]

Nope. They were used on gas engines back in the day as well.

 

[usar17]

Anyone else like to add? Would this work? Or thicker oil? Or what. I refuse to rebuild this motor when I'm putting in a different one later

 

[HotRodPC]

I'd be more apt to say the valve guides and seals are gone and you're compressuion directly under the valve covers and that's why it's all escaping there. Obviously rings rings too if your oil into the combustion chamber to great blue tailpipe smoke.
I think sky suggested about your only option. As worn as the motor is, Cheap SAE 40 weight is about all I'd run it at this point.

 

[usar17]

I'm not getting any smoke from the tail pipe. Its all coming from where oil is running out onto the exhaust manifold. And would I put a down draft tube on both vavle covers or just one side

 

[HotRodPC]

Ohhh, well then you probably just have some very bad valve guides and seals.

 

[usar17]

if so then its not worth doing anything to it is there?

 

[HotRodPC]

if so then its not worth doing anything to it is there?

IF you've got another motor in mind, NO it's not. I highly discourage a valve job on a motor this old. You'd be looking at about $200 in a valve job for machine work and gaskets, + your free labor. The newly worked heads would raise your compression enough, the tired rings would say Fugg it and give up and you're right back where you started except this time it's the rings causing the massive blow by and you would for certain have blue smoke out the tailpipe. Not sure you'd want to go thru all the hassle and work, but some new umbrella type valve seals would patch it for a short time by limiting the oil, but I'd be afraid if the valve guides are shot, then compression would just blow to seals out too in short order. At this point, I'd do the down draft tube. Drive ony when needed and get busy working on the 350.

 

[usar17]

Ok thanks

 

[usar17]

Ok im not that versed in downdraft tubes, neither is my friend.

I know the concept is that driving down the road causes a vacuum effect across the bottom open end of the tube. Now are you recommending replacing my PCV valve with a downdraft tube or replacing my breather with a downdraft tube. The oil problem is on the breather/fill tube side of the motor.

 

[skysurfer]

I would go with what's easiest first, leave the pcv in place and replace the breather with a tube. You don't need to do anything fancy, just put some hose on there to see if it helps. Try to keep the i.d. of the hose at least as large as the i.d. of the grommet and give it some height coming off the valve cover before it turns down so if there's any oil splash it will have a chance to drain back into the engine.

If it works, you could always do something that looks a little nicer with some thin wall tubing but it sounds like this is a temporary fix until the engine is replaced.