joe (pa) Posted September 21, 2013 Report Share Posted September 21, 2013 I have a 1951 cranbrook with a p23, I believe. Just purchased it and saw the oil pressure gauge was broken so I got a new one. To my surprise upon installing it, the oil pressure is upwards of 65psi at idle and completely pinned when driving. What could cause this? I don't have any history on the engine other than that it was running when I got it. some things weren't installed correctly or missing though. Fuel float retainer missing, points adjusted way out, timing off, fuel pump barely pumping, valves out of adjustment,etc... Could it be a blockage? Bypass valve spring? Seems like its not a great idea to leave it that way. Thanks for any input. Quote Link to comment Share on other sites More sharing options...
Young Ed Posted September 21, 2013 Report Share Posted September 21, 2013 I would say your oil pressure relieve valve is stuck or broken. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted September 21, 2013 Report Share Posted September 21, 2013 (edited) I agree with Ed..it is not hard to remove, polish and re-install...and do also ensure that the spring is not broken ...if stuck in place a long sheet tmetal screw will self thread into the relief piston and usually will then start spinng once threaded in so far...once that is doen carefully extract the piston...polish in a drill press if you have one handy..use 400-500 wet and dry and keep well oiled as you polish..clean the hole in the block with a bore brush and clean oil...using a q-tip to clean after using the brush...lube the piston..check for a smooth not catching fit. Edited September 21, 2013 by Plymouthy Adams Quote Link to comment Share on other sites More sharing options...
seabee Posted September 22, 2013 Report Share Posted September 22, 2013 I seem to remember when I rebuilt my engine the rebuild kit came with a few diff color springs, I installed the wrong one, when I started the engine the first time, it pegged my oil pressure gauge and broke it. The gauge never returned to zero when i shut it off. So make sure its the correct spring. Quote Link to comment Share on other sites More sharing options...
joe (pa) Posted September 22, 2013 Author Report Share Posted September 22, 2013 Yes, the old gauge was broken. The brass tube was blown up like a balloon. Hope I didn't break the new one. I will be pulling the relief spring out Monday and let you know what i find. Thanks for all the input! Quote Link to comment Share on other sites More sharing options...
joe (pa) Posted September 23, 2013 Author Report Share Posted September 23, 2013 well... the valve is completly frozen in the block. I tried a screw and even easy outs, but it will not budge!!! What type of screw would be the best to try? Any way to push it out from the back? Should i use a drill bit? Thanks for all your help! Quote Link to comment Share on other sites More sharing options...
ptwothree Posted September 23, 2013 Report Share Posted September 23, 2013 I wouldn't use an easy out. ... try a 50/50 mix of acetone and trans fluid and let it soak a day or two. Drill a hole in the middle of the piston and install a big sheet metal screw. If you have access to a torch, try heating it and prying on the sheet metal screw. You can sometimes get to the back of it but you have to pull the oil pan to do so. Some where in all this, it should come out. Quote Link to comment Share on other sites More sharing options...
DJ194950 Posted September 23, 2013 Report Share Posted September 23, 2013 Might try finding a piece of round stock that will fit inside the plunger and wiggle side to side/up and down and maybe tapping on it lightly after some soaking as suggested. Another thought? Best Doug Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted September 24, 2013 Report Share Posted September 24, 2013 the hole in the plunger is very small...the head of the plunger is rounded and the port in which it is located will not allow push through..must be extracted...a good high quality hardened screw say fof the variety for patio decks should thread into the hole...do inspect with light (mirror may be needed) to verify the plunger's hole size... Quote Link to comment Share on other sites More sharing options...
joe (pa) Posted September 24, 2013 Author Report Share Posted September 24, 2013 Well, tonight I tried to put a screw in it.... Didn't hold. Couldn't bite into the plunger. Man oh man is that thing made out of hard metal. Managed to hammer a flat tip chisel into it, that bit hard but didn't budge it. So I thought I'd just drill through it... Mushed two new drill bits. Jacked the one side of the car up 3 feet and filled the hole with penetrant oil to sit overnight. I lost for tonight but not beaten yet! Round 3 tomorrow... Does any one know if i can drop the oil pan and knock it out from the back? Thanks again guys Quote Link to comment Share on other sites More sharing options...
_shel_ny Posted September 24, 2013 Report Share Posted September 24, 2013 Thought I posted this in the AM, but must have missed "add reply after I did a preview. The inside of the plunger is .500" = or - if you try to fit something in there. My pinky works well for removal when they are not stuck. The hole is about that same depth. The small hole in the center is 1/8" The metal is very hard. You would need a quality bit to do any drilling. Quote Link to comment Share on other sites More sharing options...
JerseyHarold Posted September 24, 2013 Report Share Posted September 24, 2013 What if.... you remove the two oil filter lines, plug one of them on the block, and use a blow gun on an air hose at the other oil filter fitting to pressurize the oil system. With no retainer on the relief plunger it should pop right out. The same principle works for removing stuck wheel cylinder pistons. Quote Link to comment Share on other sites More sharing options...
joe (pa) Posted September 24, 2013 Author Report Share Posted September 24, 2013 Woo Hoo! Got it today! Boy was that thing stuck. I drilled through it then tapped the hole out, used a long bolt through a socket that rested on the block as a puller. Was afraid it was going to strip the threads out it pulled so hard but then it gave and came out! Quote Link to comment Share on other sites More sharing options...
TodFitch Posted September 24, 2013 Report Share Posted September 24, 2013 Woo Hoo! Got it today! Boy was that thing stuck. I drilled through it then tapped the hole out, used a long bolt through a socket that rested on the block as a puller. Was afraid it was going to strip the threads out it pulled so hard but then it gave and came out! Congratulations! Now, I suppose, you might be asking about where to get a new plunger. . . Quote Link to comment Share on other sites More sharing options...
joe (pa) Posted September 25, 2013 Author Report Share Posted September 25, 2013 Planned ahead on that one at least... New one is in the mail, should be here tomorrow! Quote Link to comment Share on other sites More sharing options...
greg g Posted September 25, 2013 Report Share Posted September 25, 2013 way to persevere. Quote Link to comment Share on other sites More sharing options...
RobertKB Posted September 25, 2013 Report Share Posted September 25, 2013 Glad it worked out and it was good you posted the final result and how you did it. Lots of good ideas presented in the thread as well for anyone else with a similar problem. Quote Link to comment Share on other sites More sharing options...
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