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1098 vent tube

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I do have discoloration down the side of the block but no water in oil or weird exhaust, too much to hope that it's just a head gasket? Is the $10 version from Moss adequate for a "test" or do I really need the $40 one (Payen)? I should probably try a leak down test first, pressurize #3 and see that happens?
An overhaul is not on the agenda until things get markedly worse.
 
okay, have acquired a catch can (thanks Edward!) Now how to plumb it in. I realize it's likely a band-aid. I'm thinking of coming off the vent tube into the can, back out of the can to tie in with valve cover line to air cleaner, drain back to sump via fuel pump blanking plate. I could forgo the tie in with the valve cover/air cleaner line and just vent the catch can to atmosphere otherwise.
Thoughts?

Anyone have a tappet cover plate they would be willing to part with?
I hate hacking up original pieces of the car, I'd rather experiment on a scrap part if I can.
ventplumbing.jpg


or

ventplumbing2.jpg
 
I remember that thread now too. I don't have a timing chain cover can though, early 1098's had the draft tube straight to under the car, open to atmosphere, and a line from rocker cover to air filter housing, that's it (I believe). If I do the second picture it wouldn't get any "draft" but I don't know that it really needs it. If I do the first picture I'd still get some oil in my intake (I see evidence of it no on the air filter and oiliness where tube enters the filter housing).
Here's another way, both rocker cover and crankcase lines go to can, other line from can goes to air filter to get a bit of "pull", bottom of can drains back to crank via fuel pump plate.
ventplumbing3.jpg
 
alright, maybe this:
cut the tub (I don't think you can separate the long portion from the elbow but maybe?)
and rotate the cover (can you do that?)
then the rocker cover line and the now relocated cover line T together than to one of the can's inputs
the other input on the top of the can (the red line in picture) goes to the air cleaner housing for a bit of vacuum and the bottom of the can goes to the fuel pump plate to drain back in.
ventplumbing4.jpg


maybe even stuff the can with stainless steel wool to help collect the oil out of the air?
 
I did a test today. Put a hose on the end of the draft tube, curled it up. Drove about 15 miles. Checked tube: dry. So I guess I won't go nuts with a catch can just yet. Better look harder for the source of that oil, might be further back, maybe out rear scroll seal after all but it doesn't look like it's coming out of the cotter pin hole but on the edge of the black before the flywheel.
 
Where is the oil supply for the rockers come through the head gasket from the block to the head? Might be a bad head gasket allowing the 20-50 psi oil to leak out of the edge of the head gasket. Clean the suspected area and check to see if this is the problem.
 
This is still driving me nuts, after resealing the spin on filter adapter and my fuel pump blanking plate breather.. I'm beginning to suspect that it is really only under higher revs (normal driving) that my draft tube sees oil discharge, which collects on the bottom of the bell housing, the sump drain plug and (and this is wild) inside the drive shaft tunnel, where it collects and drips out the back end of the tunnel after a while, or when I park on an uphill grade. Yes I know it may be symptom of a tired motor.
Should I:
A) stop up the draft tube, drive around and see if the leaks are gone
B) replumb the draft tube into a existing breather line
C) tear down the draft tube and replumb it so it won't "fill up" and connect with existing breather line
I'd upload a picture but I'm behind a firewall and can't.
At one point when I first got the car, I put a hose on the draft tube and ran it up, it filled up pretty fast and blew oil EVERYWHERE. But I've fiddled much since. I'm 90% sure if can stop or reroute the draft tube concept, I'd be leak free.........yeah right.
 
ventplumbing4.jpg


This looks nice. Did you do it?

I would only make a couple suggestions.
Get a PCV valve from your local auto parts (something for an old Dodge). Connect the manifold end to your inlet manifold and the other end to the "red air cleaner" hose.
Then completely remove the hose from the valve cover (and the "Y" fitting) placing instead a small crankcase air filter on the valve cover pipe.

ventplumbing5.jpg


K&N-breather-filter.jpg
 
The 1275 on my BE is from a '66 Midget. The PO filled the port for the PCV valve (that flying saucer looking thing) with solder and oil came out of every orifice imaginable. I drilled that out and put in a new PCV valve and that pretty well fixed it. It still leaks oil but no more than any other LBC.
 
racingenglishcars said:
This looks nice. Did you do it?

I would only make a couple suggestions.
Get a PCV valve from your local auto parts (something for an old Dodge). Connect the manifold end to your inlet manifold and the other end to the "red air cleaner" hose.
Then completely remove the hose from the valve cover (and the "Y" fitting) placing instead a small crankcase air filter on the valve cover pipe.
Click to expand...

That's Tony Barnhill's 1098, it was good profile shot of an early 1098 with a draft tube. I'm not sure where you're telling me to put the PVC. What would it help to have this? I used to have my head around it I thought.
So, this afternoon I put a hunk of hose on the draft tube and stuffed the end with paper towel, wiped down the bottom and went for a ride. Still had drips, must not be the draft tube after all, will keep looking. Might just be the PO made blanking plate after all, might not be sealing up well.
 
PCV valve goes to the inlet manifold from where it receives inlet vacuum. The vacuum is regulated by the valve to provide a slight under-pressure in the crankcase. The filter on the valve cover allows outside air in, therefore a slight flow of air into the valve cover, through the engine and out the side cover and into the inlet manifold. Any liquids passing through should fall into the canister and into the drain tube thereafter back into the engine.
 
Jeff the drawing you made of the draft tube altered is only taking crankcase pressure back to the crankcase (via the mech. fuel pump plate), it's pressure to have to release it, not contain it. If crankcase pressure does not have an escape route then it continues to build and will relieve itself whereever it can find, on A series engine this will most likely be at the rear scroll. The earlier systems on our car was to just relieve the crankcase pressure to the open air, the draft tube job as design was hang down low catch the under car air flow which would work as vaccum to draw out the pressure, later on car factories where mandated to catch crankcase pressure and burn them with the fuel/air mixture. Bottom line Jeff you have to evacuate the pressure not recirculate it.
 
I thought I had it that in each situation, all lines are open to atmosphere via the catch can line to the air filter housing (which really isn't "atmosphere" in the strict sense I suppose). In other words, everything leads to a catch can, which itself goes to the air filter housing to see some vacuum (which may not be necessary). But, after yesterday's experiment (see above post) I'm not so sure I'm loosing it out of the draft tube after all. The paper towel plug showed no signs of oil saturation after a short speedy run but I still had the drips. I'm turning my attention back to the fuel cover blanking plate. I'm starting to suspect that despite a gasket and permatex, it's getting out there somehow. I should just buy this (as hap suggested on another thread).

Assuming it is mostly a good old fashioned leak, then this should be fine, and the catch only maybe prevents a bit of oily mist from going into the intake and is likely not worth the effort. I most closely examine that blanking plate, maybe it's slightly warped or something.
crankvent5.gif


I'll stop wasting time on internet conjecture and just work on it for awhile (I wish I had 1/2 the time to wrench for real, that I have to waste thinking about wrenching at work......)
 
WOW! My engine is becoming an internet star - might have to get it its own facebook page!
 
tony barnhill said:
WOW! My engine is becoming an internet star - might have to get it its own facebook page!
Click to expand...

Hope you don't mind!
 
Not at all!
 
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