Jackfit

Morning Gentlemen,

327/350 Original engine, 66 . Back from complete rebuild. Stared first turn of key. I have put on about 400 miles. Changed filter, after 1 hour, full of builder grease etc. Will change oil in about 100 miles. Live in Maine, so it is cold now. Pressure on start about 30 psi. Originial oil gauge. Goes to about 15 psi at highway speeds , drops to bottom of gauge at idle.

Have owned car for 40 years and I never had high readings, Could the gauge be old and reads low?

Is 15 psi ok at 30 to 70 mph ?

10/30 oil

Jack

midyearvette

jack.....hook up a temporary second gauge to verify the reading....15 psi is way too low

capevettes

15 PSI at highway speeds is way too low and certainly, "bottom of the gauge" or 0 PSI at idle when warm is off the charts. If the car runs well it's a safe bet that the gauge is no good.

66BlkBB

I wouldn't run it that way. Just my personal opinion. I would buy a cheap gauge that has a plastic oil line and hook it up to the engine. Just to check to see if the original gauge is giving you a correct reading. If the cheap gauge reads substantially higher I would guess that the original gauge does have some problems.

Jackfit

Thanks

Will verifiy with other gauge

Engine runs like clock, no valve noise or indications of not getting oil, but I agree it does not make me feel good to see no pressure at idle, could the gauge have gotten gunk in it upon start up, from rebuild?


Jack

midyearvette

is there a fitting on the front of the block between the water pump and intake??..if so it is an oil tap....

1-2-b-67L89

I know you do not want to read this but I would verify oil gauge (as already stated several times) immediately, but be prepared that you might have a engine issue which is not common but it does happen. Your description is exactly what engines do when they have issues, not a faulty oil gauge. I hope it is the gauge but if it worked fine before I would be checking it but preparing for more drastic issues. I would not run the engine anymore than you have to check the gauge. Easier to fix than wasting away journals, etc....
Good luck and let us know how you make out,

Jackfit

Can I put the secondary gauge in that tap, I hate to touch the oil line, it does not leak and is more difficult to reach.

Run both gauges at same time to see if old gauge is off?

Thanks for tip,

I will get back with readings as soon as I put my pants on

Jack

midyearvette

naaaah...do it without pants......yes BOTH gauges

Jackfit

The filter had gunk in it after start up, could the screen also be blocked a bit. I will run second gauge , hope it is gauge, not pump.

Jack

62Jeff

Jack just as a reference point, my 65 327 with an alleged 350 horse configuration, in well-used form, shows 60 lbs at cold idle, or at speed.

Powershift

AMA Specifications (Automaker Manufacturing Association) for the Chevrolet 327 engine show 30-45 psig at 1500 RPM for normal (hot) operation.

My 1967 327/350 HP has around 50-60 psig cold at startup, 45-50 psig hot normal running, and 30 psig hot idle.

Larry

MikeM

I've never seen this but heard about it. Ask the guy that built it what kind of assembly/breakin lube he put in there. The front of the block is a good, easy place to hook up your second oil gauge.

The AMA specs as quoted above are "normal" for a 327/350 engine.

Jackfit

Thanks all of you for your comments. I will give you the results of my test and some of the things done to engine.

Was not able to get square nut off front oil tap. Water pump in way and no socket to fit, brass nut and started to strip if worked to hard

Use regular fitting at rear that supplies reg gauge

Other gauge showed same reading. 5 or less at idle 15 max at faster rpm cold, did not wait to warm up since I know what to expect.

The car has always read a bit low, even 40 years ago. 30 to 40 psi max
about 15 to 20 warm. and would drop low at idle. Engine has over 250,000 miles on it with same pump and reading but Never dropped to almost 0 at idle

The lube used for assembly was LubriMatic Motor Assembly White Grease.

Lots of gunk in first filter after 1 hr run time
Oil is clean, no smoke or bad sounds that I can perceive
Engine feels strong like I remember when I was 22 and bought car

I don't believe he changed original oil pump.
Only leak front of oil pan stated below
I did put on a spin filter instead of original canister.
I do have a small leak front of oil pan and I am going to have gasket replaced next week and will have screen and pump checked

If you believe the pump may be problem, since I will be dropping pan no problem with putting in new pump (I hope that is problem)

Car temp is at 160 after warm up. New Dewitt direct fit rad. Old temp was at 200 plus before rebuild with 20 year old copper.

Could I have put on spin filter wrong.. Does not leak or indicate any problem

I will not run engine until I hear your comments

Thanks

Jack

Ron Miller

Check to see if a new oil pump was installed. If not, and you plan to pull the pan anyway, I would certainly recommend a new oil pump at that time. Always a good idea at rebuild time, in my opinion. Then, if nothing changes, I'd try going back to the original cannister oil filter just to see . . .

Little changes, won't cost much, and will eliminate any possibility from the equation, in my opinion . . .

midyearvette

the builder should have replaced the oil pump......get a MELLING high volume not high pressure....be sure you still have the original filter plate used in conjunction with the spin adapter!! ....you won't need to go back to the canister..this should solve your problem....disconnect the idler arm at the 2 bolts on the frame...then you can pull the center link down to make pan removal easier..good luck....

MikeM

I would replace the oil pump with a standard replacement pump while you had the pan off but I don't believe that's your problem. Pumps wear and will lose pressure but they don't do it sitting on the bench waiting for the rebuild to be complete. If you put a new pump in, tack weld the pickup screen to the pump housing. Don't rely on the press fit.

I'd like to tell you something happened when you changed the oil filter over but I have no idea what it could be if it doesn't leak.

Jackfit

I did change the filter back to the canister. You know, they say the spin on is less messy, but the two times I have changed it, I got more oil on me than I ever had with the canister.

Anyway, guess what? no change, still low pressure.

I think I will keep the canister for a while.

Now, heaven forbid, if I change the pump, and still low pressure....

Is there any possibility that the oil tap opening, could be clogged in any manner from the build, or if that was so, would I not see any pressure on the gauge,

It still goes up and down , just not up as far as I would like, like a lot of things at our age.

Jack

midyearvette

.........replace the pump.........you haven't had good presure for 40 years...give yourself a treat and your engine too...

Jackfit

Thanks again everyone for the very entertaining morning and afternoon.

I will let you all know the outcome of a new pump.

Now a drink and little TV golf watching. Good to see others frustrated, I think I will take my pants off , since putting them on didn't fix my problem

Jack