Hi guys, I am looking to replace the breather tube on my 316 by using a valve cover breather with a built in PCV valve. My question is what to use to plug the breather tube hole in the crankcase? Any suggestions?? Thanks for the help!
I usually put the PCV valve in the road draft tube so that the flow through the engine is the same and your breather is the same. I'm not familiar with the RD tube on a 56 Poncho but but for my Stude engine I just cut it off and welded on an adapter to get to a hose or hard line to go to the PCV valve. Your idea will be reversing the flow of the original system so any oil baffles in that system won't work as designed. It may work but I believe it will take more engineering. JMO
should work fine. It's my understanding that your motor ventilation should be either side to side or front to back. So in your case one valve cover having the pcv and the other having a breather will work. As for the draft tube port measure the diameter and get a freeze/brass plug at the local auto parts store. Probably will be 1" or 1-1/4". Just did it on my 283.
Disregard the previous 2 suggestions. All you need to do is remove the draft tube from the valley pan and install a PCV grommet and valve in its place. Both pieces are available from O'reillys. I will get you the part numbers when I get home later today. I did this on my 347 and it works fine...
Go to O'Reilly's and get these 2 parts and a length of vacuum hose to fit the PCV. http://www.oreillyauto.com/site/c/s...=Grand+Prix&vi=1254226&year=1973&make=Pontiac http://www.oreillyauto.com/site/c/search/PCV+Valve/02180.oap?year=1973&make=Pontiac&model=Grand%2BPrix&vi=1254226&rpl=1&categoryRedirect=02180 Remove the draft tube and any grommet or seal from the valley pan and discard. Install the grommet and PCV into the hole in the valley pan. You may need a long needle nose pliers and a little lube on the grommet to get it in. Attach the hose to manifold vacuum and you're done. No cutting, no drilling.... And it looks factory. PM me if you have any questions or need a picture of my set-up.
Ditto, bryan6902. I did much the same on my 8BA flattie,...works perfect !! Best thing, the airflow thru the engine remains as engineered at the factory. 4TTRUK
Wow!!! Great responses! Thanks for all the help! I think I will try your idea Bryan6902, seems like the easiest fix with the best result. But thanks to all, the HAMB comes through again!
Just let me know if you get stuck... It's a bit tight getting at that valley pan hole, since it's right between the carb and distributor. Just be patient, I walked another member through this a few months ago. Also make sure you get the PCV installed correctly. Make sure your breather caps are good and not all caked full of grease and dirt. REsults are worth it. Looks factory, no more messy draft tube, superior crankcase breathing, no more moisture build-up in the oil.. I read somewhere that PCV's actually helped manufactuers with the long term durability of their engines just by getting condensation and combustion by-products out of the engine.
I've pulled Pontiac valley pans that had that grommet in them, apparently they did this factory on some applications. Cars in question were too new to have had a draft tube.
JUst wanted to update everyone who was nice enough to offer help with this project! I used bryan6902's advice and put a grommet and pcv in the crankcase where the draft tube was removed. I used the Dorman part number and went to the local parts store and got exactly what he said would work. As there is no Oreilies in Maine. As mentioned it can be tight getting the grommet in the crankcase. As luck would have it a 1 inch piece of conduit fits nicely into the top of the grommet and allowed me to push the grommet into place with no trouble. In fact, getting the hose securely placed on the pcv took more time. Not much room in there for a guy with large hands. The out come is great! No more draft tube, which will keep fumes from getting in the car and oil from ending up under the car. Thanks again for the help! If anyone one else needs help with this kind of project just send me a message. I have the part numbers for Dorman etc.
I'm probably the other member Bryan was referring to. Still working great! I wanted to post pics of the inside of my breather tube and filter but never got around to it. It looked like it was plugged with lard!
Glad it worked out for you! Oddly enough the reason I did this conversion in the first place was the fact I was missing hardware for the draft tube. I had the tube itselt but was missing the canister that went on the end and some brackets for mounting, so it just kind of hung there....
I realize this is reviving a super old thread, but I just went through this on my 57 Pontiac with the 347 because I switched over to an HEI distributor and the breather tube would no longer fit with the larger distributor. Where would you recommend the best place to run the PCV hose to? Originally I was planning on running it in a valve cover breather but now I’m wondering if I’d be better off drilling a hole into the air cleaner?
You run the hose from a PCV valve to a manifold vacuum source. A PCV is a metered vacuum leak. Its a simple arrangement don't over think it.
Hi All, I am very new to HAMB and this is my first reply to a post so I hope it works. Anyway, I have 57 Pontiac w/ 347 and have been looking for how to remove the breather pipe for ages. Would anyone have any pictures of the completed install please? Also, Pinnacle57 mentioned converting the distributor to HEI, which would be fantastic, and wondering if anyone has advice / pictures of this please?
Any Pontiac V 8 HEI that has a vacuum advance will fit. Also you can get the later aluminum oil filter adapter and convert to a spin on oil filter.
Thanks Old wolf, really appreciate your quick response. I have already sourced the oil filter adapter and waiting to finish other mod's before I install this. My 57 is 3 on the tree and RHD (I'm from Oz and was lucky enough to find an original RHD one here), and the gear selector linkages are in the way of the oil filter being installed, even the filter adapter that is angled at about 75 degrees. Anyway, that will be sorted soon as I have just ordered a trans adapter and have a 700r4 waiting to be bolted up and installed, then the oil filter will fit. Thanks for the advice on the HEI, I will research the Pontiac ones and see what I can get here in Oz that is compatible. I think that some of our local GM made Holden V8's used some of the same parts as the US Pontiacs, so hopefully shouldn't be too difficult to find.
I also did the PCV in the original road-draft-tube hole/spin-on filter swap on my '57 engine. In the past I've also used a factory H.E I. distributor in the old 55-60 engines, even with a dual quad setup [photo] A small amount of grinding on the intake [Offenhauser] and the cap is helpful to get some timing adjustment but it fits. In my case there was a plugged hole in the back of my Carter AFB that accepted a screw-in pipe nipple for my PCV hose. It all works fine.
Thanks Rocky, pictures are a great help. Currently running the factory 2bbl manifold & carby, but good to know about grinding necessary on the old offy with 2x4bbls as I have one of these setups which I will be installing in the near future.
Hey Rocky, I’m looking to add PCV to my ‘56 engine. Do you happen to have part numbers for a grommet and PCV valve? I’m in Australia and the local auto parts stores don’t carry anything that looks suitable. I’ve tried the links in an above post, but can’t see it - O’Reillys might not let anyone from outside the USA access the website. Thanks Jim
I'd love to help you out with a number but I just dipped into my bin of rubber thingies and picked out an old grommet that fit the hole and also fit the PCV valve, which I also picked out of one of my parts bins. Sorry.
I want to do the same thing with my 56 Pontiac with a 287 and a 2bbl Rochester carb. (The 287 came out of a 55 car) I can tell that the parts are for a 73 Pontiac Grand Prix. But anyway, where do I attach the hose from the pvc valve? To the carb somehow. I could use some advice. I could use some pictures if anyone has some. Thanks
On my 347 equipped 29 Roadster I had run a 6 X2 setup so I couldn't put anything below the manifold and I just used a rubber dorman expandable plug in the hole and put a PCV on one valve cover and a breather on the other side and it worked fine for years now.
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