Is it common for SBC oil pump pick up tubes to fall off?

Hitchhiker,
I haven't read the entire thread so I am probably parroting someone else here.

yes they come loose, that is why we tack weld them in place once we have them set. But if it has fallen out you would not have any oil pressure as a rule. I guess it could be loose enough to be just flopping around.

It could be that you have something floating in the pan that blocks or partially blocks the screen on occaision, I have seen that happen before as well. I have also seen the bypass stick intermitantly on the pump itself.

Sometimes a spun main will have the symtoms that you have mentioned even all the way to holding good oil pressure sometimes and not others or at least I have experienced that in the past. If you can drop the pan with out pulling the engine it is pretty easy to check.

Anyway like I said I am probably saying something that someone else already said.

Benno

Eddit:

One last thing comes to mind, I had one that drove me nuts once and it turned out to be a bad oil pressure sender.

 

The last 400SBC that I built I used a new Melling pump that came with a nice hardened drive shaft and a pickup tube that bolts on with two small bolts. I used Loctite on the bolts and it works good.

I learned to tack weld the tubes on from an old guy in the 60s. Measure the depth of the oil pan and set the pickup between 1/4" and 3/8" from the bottom of the pan, then tack it in place.

 

Drain and see if there is 4 qts. To long a dip stick will say full when there is a quart or more low.

 

Try this put 2 more quarts in it and see if the problem changes.My wife drove my big block suburban 30 miles home with the pick up in the pan.(Sounded like hell- lifters) I added 2 quarts and it quieted down and I knew what the problem was new pump and welded pickup fixed it. I pulled a couple of beearing caps it never hurt a thing. RLS

 

here is some pic of strap welded to pickup this came of a high rev 283 stock drag engine in a nova 1966 oil sump in front(this engine is in my roadster now)big block oil pump for wolume and bigger pipe
.srap is attatced to main bearing cap with dublle nuts and whashers the other is a sbc high wolume pump whith strap
experts say 3.5 psi pressure is enough if you have wolume on a sbc?

 

Just to up date this....I put a quart in it, problem got better....pulled the pan, pickup was still connected but rotated 45 degrees up from the bottom of the pan. I pulled a couple bearing caps everything looks decent, so I don't think it was starved for to long. put it back together everything seems great. Thanks everyone.

 

Great news!

Glad everything worked out for ya!

 

only common enough to be traditional to tack weld them in place for years now

 

Good info! I personally never heard of this before.
J

 

Yup, happened to me and cost me the bottom end of a brand new 383 stroker. Weld, braze or pin it on.

 

I just picked up my 283 chevy from the machine shop...he said the baffle in the oil pan was stopped up...it was showing about 2 quarts about full on the stick....but it only had about 4 qts in it when I drained it....that might be why the guy sold it to me...

 

I never had a problem but all mine since the first one in 1966 have been welded in not about to try one without welding. If something works why change it.

 

Thanks for the update on what you found and I'm glad it is fixed easily.

 

Good idea John.

 

Since the thing is press-fitted tin, I think most troubles arise because installation is likely to involve twisting and tilting that undersizes the tube end---especially with used part. I've seen this once, on a hotrod '55, and those symptoms that started the thread do match what happens with tube fully out; most chevy installations have pump deep enough that everything still works when not sloshing around.
A good driver makes installation easy and prevents twisting damage to tube. The best I've seen, much better than the common fork-on-a-stick type, is in Vizard's Chevy SBC overhaul book. It is just a piece of iron pipe with some clever grinding (shown in the book) that allows it to meet the ridge in the pickup nicely and drive from a very nearly straight approach. Just the pictures on making that were worth the price of the book it works so well. Still needs strap/weld/braze though! Vizard tool took me about 2 minutes of hard labor on the grinder.

 

I HAD A PICKUP AND PUMP DROP OFF THE 350 ENGINE TO MY WIFE'S CORVETTE.
In 1981 my wife and I purchased a 1980 Corvette L82. The car had a mere 1400 miles on it.
We drove to an ice-cream stand the first night of vacation one night, a very dark, unlit quiet Cape Cod road.
Road was dead smooth, freshly paved, perfect for cruising.
We hear a dull thunk about a half mile from our house. We're clueless about the noise. Pot hole? Sunken manhole cover? A rock? Wife says "What the hell was that?" I'm thinking a road issue "Nah, cant be, this road is perfect." Road is brand new I'm thinking don't have a clue to the loud thunk.
We get ice cream, then I start the engine. Sounds like solid lifters, zero oil pressure.
Drive the one mile home with noises getting louder.
Next day I have our new Corvette towed to the Chevy dealer in Hingham. She and I are both very unhappy now
Chevy dealer calls that night to tell me they found the oil pump exited the block and was found lying at the bottom of the pan.
Took several weeks to order and install a L82 long block.
Yup. Shit does happen

 

The fact that it was rotated in the pump tells you that it was going to fall out sooner or later.