Why does my 350 knock for 3 seconds when I start it? Oil pump or worse?

No Im not positive but it seems like it lasts longer than start up piston slap would be.
It doesnt sound like a dieseling sound. the tempo of the knocks is slow about 4 to 6 knocks per second

 

Dump the 20w50 if that's what you have. That stuff is too thick for your oilpump. Stressing the pump,distributer and front cam bearing. If you have 20w50 yes its hiding the worn out bearings. Your not in the desert. 10w40 is enough.. I would bet your pump is weak now and front cam bearing is shot if you have that molasses in there.

 

I was mistaken. I checked the empty jug thats been sitting by the trash cans for a few months. It was Quaker State 10/30. Maybe the filter is just full and it takes a few seconds for the bypass to open up so unfiltered oil can get through.?

 

If you do pull your oil pan and see how small the tube for oil pickup is you will understand why . it has to pull oil thru a almost 3/8 tube then thru a long 7/16 passage in block to oil pump where filter is . its struggling. So its going to take a few seconds to get oil. Chevy engines the pump is almost in the oil inside pan.pickup tube is maybe 4 inches long and goes into pump .

 

so then this must be a common complaint of the buick 350 then right? But wont these dry starts hurt the engine just a little bit every time I start it gradually leading to catastrophic engine failure? Is there any kind of additive I can put in the oil to keep the parts slick while its waiting for the oil pressure? Like slik 50 or teflon products marvel mysery oil sea foam etc??

If those passages are so narrow already, what if there is some kind of build up or constriction of sludge in there? How can I dissolve that? Is it possible with the oil pan off to somehow ream it out with a brush. Im just tryhing to viusalize, I have never seen one before?

 

Sea foam is a cleaner. I would not let it get onto bearings. I have done slick 50 and have seen the startup noise go almost away sometimes. Marvel mystery oil is good to add at oil changes but don't really stick to bearing surface when sits overnite. Zmax if they still make that . but I never tryed it even thou the stuff is made down the street here.
I think I posted a pic on another of your threads of the oil passage in block on my stroker 350 that was drilled out to 1/2 inch and 5/8 screen used. That's what I do to help oil pump problems.

 

Don't worry about it. I have had many big block and small block Buicks do this, including my late Grandfather's 30K mile Electra. I have never lost a bearing in any of them.

 

When I start the car up after being complimented on the car it makes a death rattle knock for 4 seconds. Then I politely smile and drive away but inside I feel like man I need to fix that. That cant be good for the motor. It wasnt always this noticeable. Tomorrow I will change the oil and filter and chase it with some sea foam an d marvel mystery oil unless advised against it. Thats not normal. When all those oiling mods are done, does the noise go away then?

 

So how can I use it without it getting onto bearings? Dont you just pour it into the crankcase?

 

I never heard it poured into crank case.Most people I know use it as a top end cleaner. Pour it down carb as engine is running at around 2000 rpm or pour into fuel tank.

 

I do know that seafoam is safe for the crankcase when used as directed, even in a wet clutch motorcycle. But I have never done it, but know folks who have on the motorcycle boards with no side effects. Used in the gas most often by them though, cures many carb problems without opening them.

I would seriously get something anything in there, sound like mine use to do, then one day it was super loud, [lifters were all sticky n gummy,] few sec of running worked it lose for years then one day 2 of them collapsed and caused damage on start up.

I like to run some MMO every so often in both oil n gas. Should of ran some more often me thinks....

http://www.v8buick.com/showthread.p...-cam-looks-great-the-story-continues-Help-Plz

 

Just dawned on me, if you get your oil changed at Walmart, I believe they use Fram filters:eek2:
Change the oil yourself and use a quality filter as has been suggested on here:TU:

 

He uses a Wix filter. I told him what to do 1/2 2qts of 10-30 Mobile 1 Synthetic and 1/2 2 qts of 15-50 Mobile 1 synthetic and you will be fine. Don't put ANY of the other crap into the engine it is crap. OIL keeps the motor running not that junk you can buy. Put in the zddp too. That is the only additive you need. The 15-50 Mobile 1 synthetic has some zinc in the oil. But not the 10-30

Synthetic oil will absolutely not burn I tested it with a torch in a steel cup by heating it up do the same with regular oil and watch it smoke and burn.

I have 20 years on my motor using this oil and recipe, clean as a whistle inside. No issues. Well over 500 runs in the 1/4 mile ran to 6 grand every time. Bunch on Nitrous.

 

I think Brad Penn 10W-30 is an excellent oil with no additives needed. I use it in my '69 wagon and it purrs right along. Will use it in my Stage1 also.

Try it, you'll like it.

 

I only go to walmart to buy the oil. I like Quaker State in the 5 Qt jug. I always change it myself though and been using Wix filters now since I switched from AC delco. I thought AC delco was the best until I heard about WIX and napa Gold. I dont know for sure though. What do you guys think about AC delco filters?

 

But since Ive been running regular oil and the car may not have been maintained that well in the past, what can I do to clean the sludge out? Maybe just this once some sea foam to clean it out? and then use your formula? What do you think ?

 

You could use an ignition cut-out and spin the starter for a few seconds before firing.

 

All the buick cars and motors ive had have done that to a certain extent , my 95 lesabre 3.8 does it and its pretty loud too. Ive heard it in other makes too.like people have said probably excessive clearance somewhere.