Crankcase Blow By

[Anonymous]

Does anyone know why I couldn't plumb a 3/8" rubber line from the top of my valve cover to the intake "log" ?

I have some smoke that escapes through my breather cap (new cap, too) and out from around the hood seams that I'd like to stop. I thought this would be a good choice. I was thinking a closed vent circulation setup. I don't have a closed air cleaner so I can't plumb it to the cleaners housing.


Thoughts.


-Chris

 

[Anonymous]

Stang200,

I have to ask an obvious question, what’s wrong with the existing PCV valve set-up? Have you pulled the hose and checked for suction?
You do have a PCV valve setup from the rear grommet on the valve cover to the carb spacer, right? May just be clogged.
You should have either the PCV valve set-up or a draft tube, and a 77 is too new for a draft tube.

 

[Anonymous]

Well, I replaced the PCV valve yesterday and new hose. The carburetor base is clean. I cleaned it when I rebuilt the carburetor a month ago.

Right now the motor is setup with the PCV in the front and a breather cap in the back. Originally the breather cap was plumbed to the air cleaner but since then I have replaced the air cleaner housing.

If I plug the valve cover with a non-breather cap the internal engine pressure is so great I start blowing gaskets.


-Chris

 

[Anonymous]

Chris,

If I plug the valve cover with a non-breather cap the internal engine pressure is so great I start blowing gaskets.-Chris

This won't happen if your PCV is pulling the blow-by off the crank case. It sounds to me like your PCV system is blocked somehow.
If you have good suction through the PCV valve (did you check?) and you are getting more blow-by than the system can handle you may have another problem. How is your oil pressure?

 

[Anonymous]

Have you tried a crankcase evacuator system. Mr. Gasket makes them and you can get them from summit. It connects the crankcase houseing (Area where the vavle springs are) to the header to create a vacuum in the crankcase that's proportional to the pressure. You weld a venturi into the header with a check valve on it, and run a section of hose to where the PCV used to be. That venturi creates a negative pressure in the crankcase and actually assists the oil pump to get the oil to the top. Works great on 5.0's. I am a couple of weeks away from trying it on my 200/w clifford header.

John

 

[Falcon62]

Have you tried a crankcase evacuator system.

This is really unnecessary, and ineffective, for a daily driver car. Without high exhaust velocity (4 - 5k rpm and above), it won't work anyway.

What Chris needs to do is find out why his PCV system isn't functioning properly, and correct it.

Chris - Do you have vacuum to your PCV? Pull the PCV and put your finger over the end of it. You should be able to detect a strong vacuum. If not, where does the other end of the PCV hose connect? It should go to the base of the carb below the throttle plate, this is manifold vacuum. If your engine is in good condition, you should be pulling 18 - 22hg at idle.

To me, it sounds as though your PCV system is not connected properly.

 

[Anonymous]

Okay....here's the latest. I've been very busy with home life stuff but I had some time to look into my oil troubles yesterday.

I replaced the PCV and the hose and cleaned the carburetor base where it attaches. I blew some air thru my setup before I reinstalled it and alls clear.

I reassembled everything and checked for vacuum. I think I'm getting plenty because when I plug the PCV with my finger it changes the way my engine runs big time! Alot of vacuum!

Now what? I still have smoke. The only thing that has not been fixed or replaced are the oil rings. My compression is pretty good. I think the last time I checked it, back in early March, it was somewhere around 8.8:1.

Could the oil rings be bad and the engine still maintain good compression?

One more thing...my oil pressure gauge never gets much higher than the "L" on the meter. Is this normal? Also, can I run without a PCV? Just a hose running from the valve cover to the carb. base? Nevermind, bad idea.


-Chris

 

[Falcon62]

A lot of vacuum!

That's good.

Now what? I still have smoke. The only thing that has not been fixed or replaced are the oil rings. My compression is pretty good. I think the last time I checked it, back in early March, it was somewhere around 8.8:1.

How did you determine you had good compression? Better yet, how did you come up with the 8.8:1? That's basically a static value that will only change depending upon how much carbon is taking up space in the combustion chamber/piston tops. You need to perform a compression check and document the readings.

One more thing...my oil pressure gauge never gets much higher than the "L" on the meter. Is this normal?

Based on your posts, it sounds to me as though your engine is old and tired. There are no 'fix-its' with hoses. If your oil pressure is low, and you have significant amounts of blow-by, it's only a matter of time before it quits running. I'd find a rebuildable engine and start working on it while yours is still running.

 

[Anonymous]

Well....


I have thought about a new motor or at least one I can rebuild but I haven't seen anything I would consider worth buying. The block and head I have are in good shape but the cost to rebuild the block would kill me financially (the head was rebuild before I bought the car, it was apart of the deal - trust the guy).

I think I will start looking, again, but honestly...I have trouble justifying the cost of a professional rebuild on this motor. Technically, my abilities are limited to brakes and rear ends. I can do body work but when it comes to tearing down an engine, that's different. I can tune but that's about it.

Hmmm...now if someone would drop off a 200 on my door step (preferrably mid-late seventies) that runs - then this would be great!!!

My address is:

Chris Kehn
2020 Gerard Park Lane
Hazelwood, MO 63017
314-731-9845


:rolflmao: :rolflmao: :rolflmao: :rolflmao:


-Chris

 

[DaGr8Tim]

I know this doesn't help much, but my car has a PCV at the front and a breather at the rear.

Recentally I noticed a real drop in performance. In my tinkering going over all the usual suspects, I found my PCV was clogged along with the crank case breather.

A new PCV, cleaning the breather and a new hose to my air box fixxed my problems. I've since upgraded to an aftermarket crankcase breather that sits on top of the valve cover. APC make it and it's about $10. It's really nice, and it dresses the engine bay up a bit.

I know Mr Gasket also makes the breathers that just slide into the old grommet for the breather and has a filter on top.

I should have pictures of my setup this weekend. Maybe it will give you guys afew ideas.

 

[Anonymous]

Here's an update...in case some of you wanted to know.

This past weekend I replaced my points, spark plugs and wires. I also checked my PCV and line - found nothing unusual. Added some stop smoke to the oil and it helped alot.

After all this I noticed I'm still getting white smoke through the breather cap. When I changed my plugs they looked good. No oil, or excessive carbon build up. I also replaced ALL the vacuum lines and the transmission modulator valve.

Again, the smoke is only coming up through the breather cap and none through the tailpipe. My oil guage says I have moderately low oil pressure. I was thinking that the smoke might be because of the lack of oil reaching the valve gallery and is being burned by the engine heat. Maybe? Just a thought.

I don't think it's the rings because I would have oil on the plugs, right? And I'm getting good compression.

On another matter... ... would an electronic ignition help smooth out my idle? I just can't seem to get my idle as smooth as I would like it to be. I have the timing set as best as my engine likes (10 deg intial + 8 deg vac advance) but it still seems to run a little rough (I'm thinking diesel smooth).

-Chris

 

[Anonymous]

if his oil pressure is low wouldn`t that be the oil pump ? if you buy one I`ll put it in for ya I`m not kiddin while you`re here I could check out the pvc system