Hey guys. Been following the "shop area" forums. Lots of troubles and lots of fixes. Enjoy all the back and forth. I have an issue that has developed that I'd like to poll the "audience" with. Took the "lovely" beast out for a drive today. She's been running well. But today, as we heading out through the subdivision roads toward the highway I suddenly noticed my oil pressure reading on the gauge had dropped to or near zero. As quickly as I could I looked for a clear spot to pull over (big snow banks), the pressure reading showed normal again. It seemed fine for a short distance and then the whole process went on again. I took a chance and drove home. The drop in the pressure reading happened about a half dozen times on the way, each time coming back within a few seconds. My thought is "well of course it's the oil pump", and that's my question. Is that the nature of the death of an oil pump, or could there be another reason ? My gauge is of the mechanical type of course. Not original, but a Stewart Warner replacement (2 1/16 in. round that fits in the original military dash), of mid seventies or earlier vintage. The engine is a 235 (1959 block). Thanks for reading.
In close to 60 years of working on engines, I think I've seen a grand total of three oil pump failures. Two were sheared-off drive tangs from debris getting stuck between the gears, and one was a piece of trash stuck in the relief valve, jamming it wide open. The pump was still moving oil, but it was being recycled right back into the oil pan. Your situation is likely something similar, a sticky relief valve. Drop the oil pan and the pump, and inspect it carefully for wear. Remove the relief valve spring and plunger, and look for burrs on the plunger and/or score marks in its bore. If you see anything suspicious, change the pump. Also inspect the pump pickup strainer screen for obstructions, sludge, etc., or a loose tubing fitting where the pickup line enters the pump.
While you've got the pan off, inspect all the rod and main bearings, and check the oil clearance with Plastigauge. About .0015" is ideal, and .003" is max. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I agree it's probably not the pump but I would like to know how old it is. Since I always have trouble sealing a pan from under a truck, that would be my last place to check. If this event happens while idling and revving a little, that's good because you can plumb in another gauge in the old gauge location or leave it alone and plumb one in another proper location. If you could see it from drivers seat while driving that would be really great.
Anyway, I would, in order:
1. Check the oil level of truck 2. Put on another gauge somewhere under hood. The result of this will lead the way. 3. Change filter if it has one, change oil. 4. Consider that it could be the cold. 5. Go deeper (Jerry)
D'OH! Didn't even think about the oil level- - - - -that's the logical place to start. If there's a floating pickup screen, there's a possibility of it getting stuck in the up position and sucking air, even if the oil level is only slightly low.
I'd drop the pan just on general principles- - - -the cost of a pan gasket and a little aggravation sure beats a trashed engine! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Oh wouldn't that be funny (not) if it was that low on oil. I'm always checking the oil (good at that), so that's good (although I just went out and checked again !). Replacing or adding a gauge would be the easy way out I suppose, if there's a chance it would work. About 42 bones at Summit. Good ideas.
Jerry, every time I see your "handle" I think "My pappy said son, your gonna drive me to drinkin if you don't stop drivin that..." I didn't realize for years that Commander Cody's version was a cover.
Bartamos, my thought was, if I go that route, might as well replace the dash gauge with the essentially matching SW unit (all the gauges are SW), rather than tee into the line and all that stuff. If it works differently and shows steady pressure, then that's it. Done.
And then maybe I'll drop the pan if only for "general principles" Or not.
My handle is also my favorite karaoke song after I've had a drink or three- - - -otherwise I can't carry a tune in a bucket! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Another good idea bartamos. Thanks everyone for your ideas.
Jerry. That's terrific stuff ! I've been boppin here for quite a while. I love it ! Interesting story on the original car. Would love to hear your version too, of course after you've had a drink or three. Maybe more! Ha !
Another good idea bartamos. Thanks everyone for your ideas.
Jerry. That's terrific stuff ! I've been boppin here for quite a while. I love it ! Interesting story on the original car. Would love to hear your version too, of course after you've had a drink or three. Maybe more! Ha !
I haven't heard Jerry sing, but if he thinks he needs a beer or three to carry a note, then I would suggest that the listening audience also should have a beer or three and bring their own 5 gallon bucket full of notes.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
"Alcohol- - - -helping dummies think they can sing and dance for centuries!"
Yep, that's the cleaned up, PC version of that quote! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I got to the job site this morning, read the last two posts and I was laughing my head off. I wanted to respond but I couldn't remember my password to sign in. Only had my phone. My computer fills it in automatically. Too funny !
On my topic here, I have some new info, for what it's worth. I was fixing to rig up either an additional oil pressure gauge or just a singular unit. Turned out I had another gauge but I couldn't see it, because it was in plain sight! doh! Anyhoo, I'll try to be quick. I started my engine and observed my current gauge. I ran the motor for a good twenty minutes or so in the driveway. The pressure never dropped below 20psi even when idling. Applying say one quarter throttle brought it up to much closer to the 40 than the 20 even after it was good and hot. Gauge reads 0-20-40-60-80. Finally I say "lets take her out". Driving around nothing happens at first. Then, sure enough, it drops off to near zero, but not when I'm accelerating or cruising, only during slow downs or stops. Always comes back with a little blip of the throttle. So I think alright, I've checked the oil, but maybe for whatever reason the level in the crankcase is low (or lowering) and the oil in there is surging forward and not being picked up. Then I add a quart of oil just to see what happens. Well, I could not create the condition again in about the ten or fifteen minutes I kept driving. Hmm. Brought er back to the barn. Parked on a level spot on the driveway and let it for about 10 minutes. Oil is a little high on the stick, by about a quarter inch. So maybe I was a little low starting out. Still doesn't seem right.
So I'm thinking there's nothing wrong with the gauge. There's nothing wrong with the pump itself. Maybe something amiss in regard to the pickup and or screen (never did this before). Or maybe, and I'm just trying to be logical without any real mechanical knowledge, it has to do with how quickly the oil is able to drain through what is has to, to return to the pan. While it was rebuilt (tag says) in 1974, and I've owned it since 1977, it never has been ran a lot or very far. My hunch is that it's all gooped and gunked up. Realistically, I'm thinking the engine should be overhauled, if only for a good cleaning. I don't particularly care to do that right now, and would like to try to buy a little time. Would rather try to flush it out somehow. Maybe do the ole kerosene/oil bath. Does this make any sense ?
Could be the dipstick is not the correct one for the engine. Maybe the pickup screen inside is not adjusted correctly or has some where it is pulling air rather than oil.
I think at the next oil change I would put in the correct amount of oil and then see where the oil comes on the dipstick. If not close then mark the stick to show full.
Right Roy. I'm considering that possibility with the dipstick. When changing the oil and filter in the past I've gone with 5 qts., and the dipstick shows full. I'm reading in my '60 truck manual that it takes six quarts (with filter change). Might have been a little low all these years. Sheesh
I'm thinking the pickup screen is a little high for some reason, or an air leak has developed. I'd strongly recommend dropping the oil pan for a cleanup and inspection of the inlet side of the oil pump- - - -pickup screen, tubing, etc. That oil pressure is good enough with an adequate oil level, which tells me the bottom end of the engine is in pretty good shape. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Sounds real similar to my '55 sedan I drove in High School. I had used a pan that had the baffle removed (seem to remember it was for a boat or something) Every time I would get on the brakes hard the oil pressure would drop way down, then come back up. Oil was rushing to the front of the pan and starving the pump. I drove it like that till I was able to find another pan. Maybe something wrong with your baffle or pickup?
I am going to save myself some time from responding to this heavily tempting response, only having to delete it for being insensitive to this poster. .
Last edited by 52Carl; 02/01/20173:19 AM. Reason: Deleted prior deletion.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Put some swingin' doors in that pan like we did on the dirt track!
LOL! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
"It's not hot dog- - - -it's Top Dog- - -you dipstick!" Roscoe P. Coltrane
"Well, if I was a dipstick I'd be rich- - - - -they're in oil, ya know!" Cletus
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Hot Rod Lincoln? Charlie Ryan? Commander Cody? Merle Haggard? Did I get hacked and redirected to KOMA. (I could get that from AZ on my Crystal radio kit with the antenna wire connected to the screw that holds the outlet cover on, in my bedroom. Wolfman Jack)(The entire house ground system was my antenna)
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Alright, I could have just let this one slip right on by, but, it's only right I finish the story. So today was the day I'd drop the pan and check on the oil pump pick up plumbing. Have my gasket set and a nice sunny day. Perfect.
First of course was to get er all hotted up to drain the oil. Second, I wanted to measure the oil carefully just to see what was in the crankcase. I know, get to the point. Measured just under 4 quarts ! Dunce City Man ! That's where I be ! Remember, I added an additional quart (to get to the 4) in my previous test (where I could not recreate the condition of lost oil pressure). So I went with what my 1960 truck manual says to put in (5 qts. plus 1 qt. more if replacing filter, which I was). So 6 qts of 15w-40 Rotella (actually with one pint of Lucas TB Zinc Plus as part of the six quarts).
Drove all over town and never had any issue with oil pressure, so I'm going with that for now. Took note of where on the dipstick that amount reads.
Hey- - - -an easy fix is always GOOD! Glad it worked out that way! Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
