EmTee Posted February 25, 2022 Author Share Posted February 25, 2022 The flare fitting below (right) looks like what I currently have. The 3/16" hard line passes through the center. Basically the same as in the picture Pont35cpe posted above. Link to comment Share on other sites More sharing options...
EmTee Posted February 25, 2022 Author Share Posted February 25, 2022 2 hours ago, pont35cpe said: Fitting to head is 1/8"NPT, fitting has a .046 hole. Hmmm, that's smaller than the 1/16" (0.0625) restriction that is mentioned in the shop manual excerpt that I posted yesterday. The fitting Leif is sending is 'in the mail', so I'll measure the orifice in it when I receive it. Link to comment Share on other sites More sharing options...
DonMicheletti Posted February 25, 2022 Share Posted February 25, 2022 After a couple of removals and re-installations, it gets difficult to get those fitting to not leak. They can be a real PITA. 2 Link to comment Share on other sites More sharing options...
pont35cpe Posted February 25, 2022 Share Posted February 25, 2022 19 minutes ago, EmTee said: Hmmm, that's smaller than the 1/16" (0.0625) restriction that is mentioned in the shop manual excerpt that I posted yesterday. The fitting Leif is sending is 'in the mail', so I'll measure the orifice in it when I receive it. Maybe there is a different restriction size, from the 320 and 248 engines, my example is from a 248. 1 Link to comment Share on other sites More sharing options...
EmTee Posted February 25, 2022 Author Share Posted February 25, 2022 Maybe, but I don't think my shop manual made any distinction between the two engines in this case. The oiling system description appeared to apply to both the 248 and the 320. 3 Link to comment Share on other sites More sharing options...
buick looks fine for 39 Posted February 26, 2022 Share Posted February 26, 2022 Great picture, but there is a cavity in the cylinder head where the screen fits into and the shape remains unchanged. Thanks Leif 2 Link to comment Share on other sites More sharing options...
37_Roadmaster_C Posted February 26, 2022 Share Posted February 26, 2022 (edited) I can not tell from the pictures, but the male threads , on the left fitting in @EmTee's picture do NOT appear to be tapered like NPT. They look like strait threads to me. @pont35cpe, could you put a strait edge on the threads or better yet measure the outer diameter of the male thread at both ends of the thread with a caliper or micrometer, if you have one, to confirm it is really NPT and nor strait pipe thread. Both are available and have the same threads per inch and thread angle profile. In other words, either will thread into the opposite thread, but not seat or seal properly. If you use a strait edge what we are looking for is an angle to the threads. Two strait edges would be great as you could put one on the threads and the other on the hex flat of the fitting and compare the edge angle. If parallel the thread is strait, like a bolt or machine screw. If at an angle it is NPT, angled like a wood screw kind of for example. This is really what we are trying to figure out. Edited February 26, 2022 by 37_Roadmaster_C better info (see edit history) 1 Link to comment Share on other sites More sharing options...
pont35cpe Posted February 26, 2022 Share Posted February 26, 2022 (edited) I can tell just by looking, that the threads are tapered. I measured with calipers anyways, .012 difference. Edited February 26, 2022 by pont35cpe (see edit history) 1 Link to comment Share on other sites More sharing options...
37_Roadmaster_C Posted February 26, 2022 Share Posted February 26, 2022 (edited) Ok, that proves it. So that solves the sealing issue. Now what seats the screen or does it just float in the port in the casting. As large as the screen is it would still filter just as well. Now on to the orifice..... Where, how big and all that. Also, thanks @pont35cpefor your effort and help! It is appreciated!! Edited February 26, 2022 by 37_Roadmaster_C (see edit history) 2 Link to comment Share on other sites More sharing options...
pont35cpe Posted February 26, 2022 Share Posted February 26, 2022 2 hours ago, pont35cpe said: I can tell just by looking, that the threads are tapered. I measured with calipers anyways, .012 difference. I just wanted to state that the 1/8NPT is 27 threads per inch(tapered), and the line fitting is 24 threads per inch(straight). Picture at the beginning that EmTee shows screwing line into head without the "fitting", he is actually screwing 24tpi(straight) into a 27tpi(tapered)hole. 1 2 Link to comment Share on other sites More sharing options...
pont35cpe Posted February 26, 2022 Share Posted February 26, 2022 (edited) 2 hours ago, 37_Roadmaster_C said: Ok, that proves it. So that solves the sealing issue. Now what seats the screen or does it just float in the port in the casting. As large as the screen is it would still filter just as well. Now on to the orifice..... Where, how big and all that. Also, thanks @pont35cpefor your effort and help! It is appreciated!! Orifice on my fitting, .046. Screen from Leif is on the way, then can measure length of screen and depth of hole. I still think the screen actually collapses a little when screwing the fitting in, which keeps screen tight against the bottom of fitting. Am i nuts or what? Edited February 26, 2022 by pont35cpe (see edit history) 2 Link to comment Share on other sites More sharing options...
EmTee Posted February 26, 2022 Author Share Posted February 26, 2022 I'm going to clean the cavity that the screen fits into when I take it apart to install the NOS one from Leif. I did pull out some gunk the last time, but next time I'll use a small, round brush I have and flush it with some brake cleaner. From what I see, I think the screen just sits there in the cavity. I agree, it will probably collapse if the fitting butts up against the brass collar, but if not, I think it just sits there and catches whatever passes by. The main purpose is apparently to keep particles from fouling the 1/16" orifice at the input to the rocker shaft. 4 Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted February 26, 2022 Share Posted February 26, 2022 FWIW, I have just read the oil supply definition in the 1950 Shop Manual. By this time the oil filter was standard, I guess, as the text says all oil to the rocker arms is filtered, and goes on to describe the filter. It then mentions the restricted "pipe " fitting which is installed on top of the head, under the valve cover. NO SCREEN. So, I would think, by this, if the engine has a filter the screen is not NEEDED. The restricted fitting is. Ben 2 2 Link to comment Share on other sites More sharing options...
EmTee Posted February 28, 2022 Author Share Posted February 28, 2022 (edited) I received the fitting and new screen from Leif today (Thank you! ) The oil hole in the fitting measures 9/64". Based on my tap & die it looks like the fitting threads are 1/8" - 28 BSP (both the male & female). The female end has a profile that does appear to be the inverse of the fitting attached to the tubing. I was wondering whether a typical inverse flare fitting would work (in the event that I couldn't obtain an original style fitting), but any modern fitting would have a straight flare and not the curved profile of the original. A new fitting might still work, but it wouldn't provide as much contact area, so it may leak over time or require periodic tightening. "Plan B" was to cut-off the male fitting I have on the tube and find a 3/16" compression fitting with a body that would thread into the head (with or without adapters) and use the compression nut/ ferrule on the tubing. Fortunately, Leif saved me from that scavenger hunt! Edited February 28, 2022 by EmTee (see edit history) 4 Link to comment Share on other sites More sharing options...
Bloo Posted February 28, 2022 Share Posted February 28, 2022 (edited) That fitting is threaded sleeve. What you have should screw in it and work. Normally you don't replace the nut. If you do need it, Blackhawk Supply has them. This not compatible with double flare in any way. BSP? Straight threads? Not NPT? Edited February 28, 2022 by Bloo (see edit history) 2 Link to comment Share on other sites More sharing options...
EmTee Posted February 28, 2022 Author Share Posted February 28, 2022 I agree, I plan to use my original nut (currently on the tubing) with the sleeve from Leif. I plan to install these tomorrow, so more to come... 1 Link to comment Share on other sites More sharing options...
EmTee Posted February 28, 2022 Author Share Posted February 28, 2022 9 minutes ago, Bloo said: BSP? Straight threads? Not NPT? I'm pretty certain they are tapered threads. I happen to have a 1/8" -28 BSP tap and die. I don't have the NPT version, but holding the male fitting against the tap and 'eyeballing' them the taper seems to match. According to the Internet (so it has to be true) BSP uses a 55* taper while NPT is 60*. The tapers of my BSP tap and the fitting look the same to my eye; but they're not what they used to be... 1 Link to comment Share on other sites More sharing options...
Bloo Posted February 28, 2022 Share Posted February 28, 2022 Ok I just looked that up and I now think what I have always heard called BSP in the USA is really BSPP. The difference is no taper on BSP(P). If you have no taper, which seemed logical with a screen that looks like that because the fitting would be able to bottom on the screens ring. But, there would have to be a flat shelf or seat in the head for the screen's ring to squeeze and seal against. If there is no seat or shelf in that head for the ring to bottom on, then the fitting probably is tapered threads. If it is tapered threads, it seals on the threads and is probably NPT. No reason I can think of to use a British standard pipe threads in the US at that time unless you needed the straight threads. Link to comment Share on other sites More sharing options...
EmTee Posted February 28, 2022 Author Share Posted February 28, 2022 6 minutes ago, Bloo said: If there is no seat or shelf in that head for the ring to bottom on, then the fitting probably is tapered threads. I don't think there's anything for the fitting to seat against, but I'll pay close attention to that tomorrow and try to get some pictures of the cavity in the head. 1 Link to comment Share on other sites More sharing options...
NailheadBob Posted March 1, 2022 Share Posted March 1, 2022 On 2/22/2022 at 10:31 PM, buick looks fine for 39 said: Emtee needed a fitting and I wanted to make sure I had the correct fitting for him. To my surprise I had 2 fittings which seemed identical, but the orifice diameters were different. I then pulled a fitting out of a 1939 248 engine and the orifice diameter was 1/16th inch. After that I pulled a fitting out of a 1939 320 engine and the orifice diameter was 1/8th inch. I guess empirically it makes sense the larger engine would require more oil supply to the rocker arm assembly. I never realized this before. Thanks Leif I am thinking, @EmTee fitting orifice measured 9/64" and would be used WITH screen in cylinder head see group # 1.917 listed under pipe, crankcase to cylinder head oil, allowing more oil into cylinder head and oil was reduced because of going through/around screen and this not flood rockers with oil. AND, @buick looks fine for 39 one fitting orifice measured 1/16" was used when car was serviced when screen was removed from cylinder head (see group # 1.928 connector, crankcase to cylinder head oil pipe) would reduce the amount of oil passing in cylinder head WITHOUT SCREEN as to not flood the the rockers. Bob 1 Link to comment Share on other sites More sharing options...
buick looks fine for 39 Posted March 1, 2022 Share Posted March 1, 2022 Great thought Bob 1 Link to comment Share on other sites More sharing options...
EmTee Posted March 2, 2022 Author Share Posted March 2, 2022 A 9/64" drill bit fit perfectly into the fitting that Leif sent to me. I think that fitting is indeed the one intended to be used with the screen in the tapped hole at the front of the head below the the valve cover. I think the other fitting, with the 1/16" orifice is to be used at the other end of this passage - where there is another short 90* piece of tubing that feeds the rocker shaft. That's where the restriction is made to reduce the flow to the top of the head. The screen being ahead of this would presumably keep 'chunks' from fouling the 1/16" orifice. Link to comment Share on other sites More sharing options...
EmTee Posted March 2, 2022 Author Share Posted March 2, 2022 I installed the fitting today and the bottom line is everything went together as expected. Here's a picture of the new screen beside the temporary tube that I had installed to stop the hemorrhaging... I flushed the cavity with WD-40 and gave it a swish with my little 'bottle-brush'. Nothing really of note came out and it seemed to be clean inside when I looked into the opening with my dental mirror. The following is the best picture I could muster... Next, here's the same shot with the new screen installed. The brass collar on the screen is recessed somewhere between 3/16" to 1/4" relative to the opening. And here's the final installation, which should look the way Buick intended. I didn't run the engine yet, because the weather wasn't going to allow me to run the car up to temperature today. Thursday looks like a possibility, so I'll verify no leaks then, however, the way it went together I'm 99.99% sure that it will be fine. 7 Link to comment Share on other sites More sharing options...
EmTee Posted March 2, 2022 Author Share Posted March 2, 2022 (edited) The next job today was to address the coolant weeping from the upper hose where I installed the stocking filter. To fix this required disassembly of the entire upper hose, including the Gano and the stocking filter, so I decided to check them to see what had been 'caught' over the brief time that they had been in service (~2 hours and maybe 10 ~ 15 miles). Good news is there was one small flake in the Gano and some fine 'sand-like' particles in the stocking as shown below. I rinsed both filters and re-installed them, but this time I was careful to try to keep the stocking from sticking out beyond the hose. I mostly succeeded, but there is a sliver of stocking showing where the hose is closest to the radiator. I'm hoping that if there is any weeping at that spot, it will be very minor and I'll live with it until it's time to make another filter check in about 200 miles. Now: Before: Edited March 2, 2022 by EmTee (see edit history) 6 Link to comment Share on other sites More sharing options...
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