Started my 63 up and the oil light stayed illuminated

all appeared normal, but then the engine began to make noise

The car is now safely in my garage.

checking the service manual, changing the oil pump is very involved

can the pump be spun through the distributor like a dodge motor to check its operation?

any other insights it advice?



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Perhaps stuck open pressure relief valve in the oil pump housing. This is the most common reason I have seen sudden oil pressure drop and engine noise. If occurs gradually, I’ve seen blocked oil pickup screen cause a drop in oil pressure.

Thx for the replies

it appears to get to this, I have to pull the front of the engine off.

anyone got to this without that?

No need to remove front engine cover. Pressure relief valve has large end cap bolt. Remove and spring and valve should slide out. Cover can also be removed via four 7/16” bolts. See shop manual for illustration of oil pump assembly.

Follow Jason’s suggestion regarding getting to the oil pressure relief valve 

Glad the front cover does not need to be removed as that is more labor intensive 

Suggest you clean that valve channel first to see if that is your problem 


Hi Jason

I will try cleaning the channel you speak of

if I remove that end nut, are you able to clean that all out?

if I pull the cover plate off, can you check the pump operation?

have you ever seen a pump fail?


Yes the oil pump can be spun thru the dist shaft on our year cars 

To get to the oil pressure relief valve the engine front cover has to be removed and debri cleaned out of the channel there 

To get to the oil screen —the oil pan has to be removed and the screen inspected 

Sure you have checked the oil level on the dip stick first


Could an oil filter get so full of debris  that it could influence oil pressure in a negative way ??

To the best of my knowledge —-there is a by pass that the oil can take if the oil filter gets full of debris and fills up with junk 


Am going to change out the oil filter and drain a bit of oil from the pan and look at it

will also spin the pump to check oil pump output

I have a long octagonal rod that I used to oil my 69 mopar 318 after overhaul prior to breaking in the lifters

can this be used to spin the pump?

Mark, A stuck pressure relief valve has nothing to do with "spinning the pump". The pressure relief valve simply overcomes the spring pressure at a given oil pressure and pushes the valve out.  If their is debris,etc. in that cavity the valve can get stuck in the open position meaning the oil pump cannot build up any pressure. 

Until you figure this out I would not run the engine other than a quick try to crank and see if issues is resolved. I would remove the valve end cap bolt, and spray some cleaner lubricant up in there and try to work a clean cloth or similar material up in the cavity and  make sure the valve slides freely up and down inside the cavity before reinstalling. If the valve has some corrision on the the one in picture below I would take some very fine sand paper (400 grit or better) and smooth down. 0000 Steel wool and WD40 is also good. 

Below is a picture of the oi pump cover. If you remove it, it would give you easier access to clean the pressure relief valve.  You will also want to prime the pump if you remove the cover. If you just remove the relief  valve it probalby will not need to be primed.


Thx Jason

I misspoke.....once the regulator is checked, I would try to spin the pump to check if its working

thanks for the going to try and hit this tomorrow

If valve is beyond saving you can get them new with the oil pump kits that includes the valve, spring, gasket, and 2 gears.  When I rebuilt my engine in 2012 all new parts went inside my oil pump. If yours is just sticking, I would clean and lube and see if that does the trick. Again, this is one of the main causes. A clogged oil strainer due to say nylon teeth coming off the cam timing gear would be another.  If you get the the oil pump repair kit, be sure to get the one correct for your year. The 63 version is usually a bit more than the 64/65 verson.



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