I took apart a 49 chrysler flathead 6 about a year ago ( doing rings and bearings). Well I'm putting it back together and ran into a problem. These pistons have 4 rings ( 2 compression )and ( 2 oil control rings ) 4 ring grooves in all. I forgot how they go back on ! The oil control rings are a one piece style ( never used this type before)....and the the normal 3 piece oil ring with has 2 scrappers and the center expander ring. So heres my problem...I'm not sure where the (normal 3pc oil ring) goes I put it on the very bottom groove. BUT I'M not sure that is correct ?????? Someone please help me out !!!! I've never worked on a flathead...and never work with pistons that have 4 ring grooves..... HELP !!!!
Where did you get the new rings? Sounds kind of weird if the set comes with one modern 3 piece oil ring set, and one single piece cast oil ring....is that what you got? your post is sort of confusing. Anyways, I'd just make sure the rings fit properly, and put it together as you're doing now. If the rings fit correctly, that is, as far as width and gap.
Your missing the point. The piston has 4 rings grooves. The top 2 are for the comperssions rings...and there are 2 lower ring grooves are for two different type of oil contol rings. The two types of oil contol rings are the normal 3pc type.....and also a wide 1pc oil control ring. So this piston uses BOTH of these oil cotrol ring. I put the normal 3pc type in the lowest groove...but I'm not sure if that is correct.
Where did you get the new rings? What brand are they, if any? Are they newly made, or old stock, or what? Did they come with any instructions? Do you have the shop manual for the car the engine is from? I had the point the first time, too...I'm trying to help you figure it out. The 4 ring engines I've worked on weren't like this, so it helps to get all the information.
I did some googling and found the solid oil ring goes on the bottom with the 3 piece one in second place from the bottom. Look here; https://p15-d24.com/topic/55731-piston-ring-order/
I have the information in a factory manual. If you want me to look it up, let me know which car model and which engine you have. 23" long block or 25" long block.
I'm not going to be much help, but here goes. 1949 Chrysler Silver annerversry Convetable Model. I can not tell you if the block is 23-25" (as I will not be back at the shop till monday) All of the engine parts came from " oldmoparparts.com " Any info you can pass along would be helpful...(sorry I'm not much help, ..never worked on a flathead before) . The paper work with the rings was very unhelpful . Basically did not say which groove the oil rings were to be installed. The manual I'm using is not a factory manual...and does not have very detailed pictures.
All the engine parts came from "oldmoparparts.com" the instructions were not helpful. The manual I'm using has very poor pictures. I know your trying to help..thanks
I would have put it together like you did, apparently that's not right? Hey, I learned something, too...
Well I feel a bit better knowing that someone else would have installed them like I did. Thanks for your help.
I just found a video showing the correct way the oil control rings are be be installed (and yes the 3PC oil ring with the scrappers goes under the second compression ring/ then the 1pc oil type ring in the bottom groove) . Looks like I will be removing the pistons and moving the oil rings. But at least I found out now, while the engine is still on the stand, so thats a good thing...Thanks to all that of you guys that were helping me out.
It's probably because the 3-piece is more effective at controlling the oil film, and if it were on the bottom you'd have less oil on the walls to lube the skirts. Sometimes folks will leave the bottom oil ring off, since the 3-piece ring does an adequate job of controlling the oil film.
I can see how that would work. As for me since I have to remove the pistons, I will put the lower oil control ring back on. Thanks
Just wanted to pass this on: The 1948 Chrysler Service Manual shows the bottom two oil rings as being the same (cast iron) (?). I could go through some old Motors manuals but it's near zero in the garage and I have heart problems already. A side note: all the 4 ring pistons I can remember had the 3 pc segmented ring on the bottom groove. The cast iron 3rd ring often comes with a wavy expander that goes behind it. I don't often work on Chrysler products any more so I could be wrong. Also the paper sleeves that rings used to come in were always marked as to what groove they went in. Wonder whatever happened to that?
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