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PCV installation results

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Nomad, you are absolutely correct! The more I dig into these things the more types I find. Some have diaphrams, some springs, and some are gravity. The orfice inside the PCV is not an indicator of the amount of flow on the gravity models, just make sure they are verticle. I hope I can find a generic PCV that meets the vacuum specs for a 1275 and get rid of the 'restrictor' I placed inline.
Thanks, Rut
 
David,
I had to reread this thread since it's been so long ago. My final solution was to install HS2s. I had a set of HS2s that use the PCV valve and decided to move to a newer ebay set with the Y connector. This solved all of my problems with smoking and rear seal leaks. The car came to me with the Weber installed and I didn't really understand it and the connection to the rear seal leak.
HTH, Rut
 
David,

I also had a major issue with leakage from the rear seal on my transplanted '66 1098 in Bugsy my 68 Sprite. Put it this way, I thought I'd purchased the Exxon Valdez. Discovered the DPO had plugged the line coming from Timing Cover with a 4" long 3/8 Ratchet extension bar(a nice addition to my tool chest). Line going to vacumn on intage manifold/valve cover/ wherever it goes as I scratch my head, was plugged with a broken off spark plug. Amazing the things the DPO did. All blowby from rings was pushing oil directly out the rear seal. Crankcase ventilation via area of least resistance.

Replumbing properly including adding a flying saucer PCV Valve stopped oil from pushing out the rear seal. That along with a vented oil filler cap did hte trick for Bugsy. Bugsy still marks his territory but a single drop vs. large puddles and cardboard is cheap.
 
Jim & Rut,

thanks for your replies. My car has a 948 with HS2's, a vent on the valve cover that goes to the air cleaner, and a vent on the side cover that is open to the air and points down. My carbs do not have the hookup for the y-connector.

The engine is out of the car now for painting, I'm researching the best way to set-up the crankcase/pvc system before I put it back in. The new air cleaners will not have a conection for the valve cover vent.
 
David,

Are you indeed experiencing an issue with leakage from the rear seal. Or just trying to clean things up. The pancake valve provides a measured orifice for negative crankcase pressure. Needs to be used with a vented oil filler cap I do believe. Your car obviously has an "as designed" LBC Chassis Rust Prevention / Lubrication System.
 
I went with the pancake stuff PCV (that I got from Bill L) for my log-style intake manifold with HS2s. I ran a hose from the oil separator to the unit and then directly into the manifold. It sort of worked... until one day I sucked a mess of oil through the unit and was in a smoky (embarrassing) wonderland. So, my next plan is to dial down that vacuum a bit by narrowing the line to the manifold.
 
Boink said:
I went with the pancake stuff PCV (that I got from Bill L) for my log-style intake manifold with HS2s. I ran a hose from the oil separator to the unit and then directly into the manifold. It sort of worked... until one day I sucked a mess of oil through the unit and was in a smoky (embarrassing) wonderland. So, my next plan is to dial down that vacuum a bit by narrowing the line to the manifold.
Click to expand...

What's "pancake stuff PCV"?
 
Jim_Gruber said:
David,

Are you indeed experiencing an issue with leakage from the rear seal. Or just trying to clean things up. The pancake valve provides a measured orifice for negative crankcase pressure. Needs to be used with a vented oil filler cap I do believe. Your car obviously has an "as designed" LBC Chassis Rust Prevention / Lubrication System.
Click to expand...


Long story short... I decided to paint my car. While prepping to paint, I decided to clean up the wheel wells, which led to cleaning the under carriage, which led to pulling the rear axle and tranny to fix leaks, which led to pulling the motor because it was the only thing left.

My car was covered in "rust preventative" on the bottom. The oil filter adapter was leaking, the diff pinion seal was brittle, transmission tail seal was leaking. I think everything is fixed now, I'd really like the car to be "leak free"

I've cleaned, repaired and painted the axle, springs, diff, tranny and the engine will be done this weekend.

Now that everything is so pretty, I want to keep it that way. I've been reading everything I can find on the various crankcase ventilation and PVC systems used on these motors over the years.
 
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I've also read through the old posts on pcv systems, and I'm still confused. Can anyone post a simple drawing/diagram of how the pancake pcv valve was originally connected? Pictures are helpful but it's not always easy to figure what goes where. My particular engine is a 1098 w/hs-2s. Any original ventilation parts were dumped, and the bottom of the car was covered with oil. Most seemed to be from the side cover breather.

Thanks, Jim
 
If your car had the side cover breather it must have a 10CG engine. The pancake PCV wasn't used until the 10CC engine. it hooked up to the oil separator on the front timing cover then to a barb on top of the intake manifold. If you have a oiley 10CG it may be just because of wear or shrunk and dried out seals.
 
My car was covered in "rust preventative" on the bottom. The oil filter adapter was leaking, the diff pinion seal was brittle, transmission tail seal was leaking. I think everything is fixed now, I'd really like the car to be "leak free"

[/QUOTE]
David, such an endeavor could lead to madness!!! These are British cars!!!:congratulatory:


Kurt
 
My mistake on terminology. The engine is a 10CC big bearing with the big can on the front tappet/lifter/inspection cover. The intake manifold has a hex head fitting cut flush and brazed shut in the center hole. I assume this is where the pancake valve goes. I can't look now to see if the cap is vented or not.

Because the engine was out when I got the car, I don't know if the "can" was just vented to the atmosphere. I think it probably was. The application is a bugeye.

Jim

Jim
 
So, the total of emissions/crankcase ventilation on the 10CC 1098 is the oil separator "can" on the front side cover, connected by hose to the pancake PCV which attaches via a short hose to the fitting on the top of the intake manifold. Like the picture?

The valve cover is plain unvented, and the cap is unvented?? And, nothing to air filoters??

Jim
 

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jjscott said:
So, the total of emissions/crankcase ventilation on the 10CC 1098 is the oil separator "can" on the front side cover, connected by hose to the pancake PCV which attaches via a short hose to the fitting on the top of the intake manifold. Like the picture?

The valve cover is plain unvented, and the cap is unvented?? And, nothing to air filoters??

Jim
Click to expand...

This is largely what I did (with my 1275), though my separator is bit lower and in front. I plan to experiment with the small tube from the pancake into the stub out of the intake manifold. The pancake unit is a very simple beasty (with a rubber membrane and a spring-loaded plate). Evidently, I've occasionally sucked a large enough vacuum to pull oil all the way into it (excessively so).
 
This article makes it all make sense:

https://www.mgaguru.com/mgtech/engine/cv101.htm

It is 3 pages, read them all...


After reading that, I want the official PCV valve. Where can you get one?
 
David, thanks for that link; it explains it all. The pcv valves are available at Moss, and I assume from the other suppliers as well.

In my case I need a vented cap. Moss shows an OEM and an aftermarket, $27 vs. $7. Do the aftermarkets work just as well?

Mark, could your issue be related to the valve cover air volume and not the size of the opening going into the manifold. The MG article in the link indicates the air in through the top has a significant effect.

Jim
 
All the usual suspects list the PCV valve, no one has them in stock - that I can find.

Moss has one for the TR250/6 - Is it the same one as the sprite/midget/MGB? - It looks the same, but they only show the top in the pic.
 
Jim the 10CC is supposed to have a valve cover cap that is vented with little filter inside the cap. I'm sure that how much air this lets in is closely related to how the PCV works but I'll bet they are not available anymore so you may have to experiment.

Kurt.
 
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