Cadillac 331ohv v8 engine number

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    • #5562
      Max SowerbyMax Sowerby
      Participant

      Hi I am trying to find my engine number on my J2 as I know my car has had a number of engines in it’s time. It has a very badly fitting dipstick and sheaf which is leaking oil onto the exhaust which looks like I am doing the 007 smoke screen which I would love to replace . It also leaks oil from the the oil filler cap which has a drilled hole in the top. The engine has been modified to give a modern oil filter bypass which also has a breather so I was wondering if I could seal the hole? I have searched all the usual places to find the number and the only numbers I can see are obstructed by the bottom of the oil filler pipe and heat tray below the carburettors.see picture any help would be most appreciated. Max

       

    • #5563
      Neil BennettNeil Bennett
      Participant

      The engine number is stamped on a boss on the front of the block, just by the right cylinder head.

    • #5564
      Max SowerbyMax Sowerby
      Participant

      Thanks Neil for responding That’s where the oil filler goes down and a heat tray under the carbs is I can just see a couple of numbers which will take a lot more work to reveal. Thanks for confirming I was looking at the right thing. Max

    • #5565
      Max SowerbyMax Sowerby
      Participant

      Engine number

    • #5566
      Neil BennettNeil Bennett
      Participant

      Difficult to tell from your photo, but the engine number is at the front of the block on a boss by the #2 cylinder, ie. on the right of the block looking forward.

      I hope this leads you to it.

      There will be ten digitsl: the first two are the year of manufacture, the second two are the model of the car it was originally fitted to, and then a six digit serial number.

       

    • #5567
      roger murray-evansroger murray-evans
      Participant

      Max, As Neil has described, it’s at the front most extreme part of the RH side of the cylinder block.However, It can be prone to disappear when the block is resurfaced on the mill.There is occasionally another point where the number is stamped, certainly on the very early 1949/50 blocks, and that is on the top of the bellhousing area of the block, about 2″ to the rear of the distributor hole, on a small flat area integral with a casting rib. As it’s not a milled surface, the numbers are stamped straight onto the surface of the casting.As a matter of interest, many of these early blocks don’t always follow the normal/later numbering practice as described by Neil, but have just a short letter+number combo, such as 6M55 or 6M183.Certainly some of the earliest works Cadillac engines for J2 and,I believe, JRs had these.The later 365/390 blocks, I believe, also have an engine number stamped on a machined surface on the lower, left hand side of the block  in the area of the dipstck tube base/sump flange.I’m hoping your car doesn’t have one of these!Regarding your oil leaks.It may be prudent to extend the dipstick tube to the top of the block.Will require an appropriately longer dipstick!This should alleviate overspill especially on hard right hand corners.The ‘normal’ oil breathing arrangement of a ‘road draught’ tube at the back of the lifter valley cover, can be utilised for purposes of MSA spillage requirements by shortening the tube, rotatating to point at the gap betwix the rear of the LH inlet manifold and distributor and fed into a catch tank on the LHS of the engine bay.Likewise, you may wish to replace the oil filler/breather cap arrangement, by having a screw on cap without a hole, and letting in a breather pipe to also end up at the catch tank.

      Hope this helps

      Roger

    • #5574
      roger murray-evansroger murray-evans
      Participant

      Max, having re-read thru my old files of the Cadillac numbering system of the day it would seem that my memory wasn’t too far out, but it would appear that Cadillac engines were issued a seperate engine number upon manufacture (at the rear) and those destined for non Cadillac applications were not stamped at the front right of the block at all.This front numbering only happened when the recipient Cadillac vehicle was allocated that engine and that vehicles’ VIN was then stamped on the front of the block.The engine fitted into my J2X is a 1950 block and has the early EUN at front and back!This leaves you to uncover the rear stamping to id your number, and potentially you have the possibility that yours was always an original non-Cad fitment or, as I mentioned in my earlier posting, machined off during an earlier decking process to straighten the top of the block.

      Roger

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