Another case of [not so] "good" advice from parts store

[6SENSE]

Here is another one, this time from another guy at another store. This happened to be the manager who all the other guys there looked up to as THE source of information.
Just replaced #2 rod bearings on a .307 in a Cutlass I acquired. Aside from diagnosing the knock issue coming from this rod, the car had issues with low oil pressure, so figured Id change out the oil pump and screen while in there. A hi-volume pump is only $3 more than stock type so went to get it. This guy starts questioning if Ive done work on the engine such as boring it out or putting a bigger cam in, "because it doesnt need the hi-volume pump and if I use it there will be problems". He goes on to say that oil will go where you dont want it to and you will have too much oil moving. Oil will go past the rings. He asked me "..if I ever heard anyone say not to over fill your oil?". I seem to resort to the "dumb" role when these situations come up because you can never win a argument with these guys and its easier this way, so I just told him I only heard about that when it comes to transmissions, and that extra oil in the engine will find its way out if it needs, and left it at that.
I hate misinformation! There is 200+psi in a tranny and it is [for the most part] sealed. The engine is not sealed air tight and is what, 60-80psi max at peak? Oil going past the rings because you use a hi-v pump!? Hi-pressure and Hi-volume is too different things for one............ never mind, you get the point. Besides the pure entertainment factor, I have just started to feel that there is some benefit to sharing these stories for those who arent as mechanically inclined and/or lack the automotive knowledge that others do. I see too many people go in to these stores and come out with the wrong instructions/information and its not there faults. I know that these employees dont get paid high dollar so I dont even expect them to "know-it-all", IMO they should just have a knowledge of the parts and keep the mechanic "opinions" to themselves IF they dont really know. If they were Master Mechanics I dont think they would really be working there, now would they?
Again, let me know if I am not thinking correctly on this subject...because I will be putting the hi-v pump in shortly
Thanks

P.S. This instance, and the one about mixing synthetic oil in my other thread from about a week ago were both at Auto Zone. Maybe someone needs to tell Jesse James about this stuff since his face is plastered all over the front of the place now He'd probably go off on em' pretty good if he heard some of this stuff.

 

[gn1220]

I've heard High volume pumps can suck a stock pan dry. They move so much oil that the oil doesn't have time to make it's way through the motor and back to the pan. Maybe this doesn't apply to Western Auto pumps but you might want to put the stock pump in it and use the $3 for lunch. Don't think you really need a high volume pump in a stock 307.

 

[Slow91z]

The only problem i have heard with high pressure or high volume oil pumps is they put more strain on the cam which can wear out dist. gears or oil pump drive, stuff of that nature.

 

[6SENSE]

Thanks for the replies guys. Check this out : http://www.melling.com/support/bulletins/view.asp?id=12 Just found this. Good reading
I had already went ahead and completed the job a little while ago.....with the hi-v pump. I wasnt too worried, but for any doubt that I may have had, the Melling site made me feel a bit better

 

[Rickracer]

If you're going to run an HV pump.....

...you might want to make sure all the oil drains are clean. Most motor have cast hole for oil drainback, and most have casting flash in them. 10~20 minutes spent with a carbide burr, or a sandpaper roll will take care of these concerns.

Disclaimer: Do not do this on a motor that is together and in the car!!!

 

[ViciousV6]

"..if I ever heard anyone say not to over fill your oil?". I seem to resort to the "dumb" role when these situations come up because you can never win a argument with these guys and its easier this way, so I just told him I only heard about that when it comes to transmissions, and that extra oil in the engine will find its way out if it needs, and left it at that.

I was always under the impression that it is bad to overfill the oil. It will not necessarily "find it's way out" in good places.

 

[smokin'6]

Many have not recommended the hi vol. on the TR's. Might be different in the case of your 307.

 

[6SENSE]

Originally posted by ViciousV6
I was always under the impression that it is bad to overfill the oil. It will not necessarily "find it's way out" in good places.

Let me clarify that Im not talking about someone who went way overboard filling there oil adding litteraly qts over full. But if the oil IS somewhat overfilled, especially on these old engines, I dont think there is any problem. When it comes to transmissions I look at it much differently, but we are talking about engines with an oiling system that usually have somewhere in the neighborhood of 15psi at idle, maybe 40psi cruising, etc..... I do not see the oil getting forced anywhere, certainly not past the rings . The engine oiling system already has a breather(s), not to mention when you add larger aftermarket ones. Where you are probably more likely to find it is, [yes] where you probably wont want it either, is on the outside of the engine. A saying that I DID use to hear a long time ago from some "old-timers" was if you overfill your oil youll find your leaks. Valve cover gaskets, oil pan gaskets, etc. etc., anyone with a Buick .231 knows all about this

Anyway, looking at the gauge there is a definate improvement in the oiling situation. The engine always ran decent. Only problem is I still hear the knock noise in Drive when the engine is warmed up. I pulled the #2 plug wire and started it up and the noise is gone. Guess if it wasnt the rod bearings it must be the piston pin? What you guys think? Bearings did not look bad but were worn out of spec so I changed them thinking that was the problem. Spec is roughly (dont have exact #s in front of me) between .003 and .004. These were .006-.007 (according to plastigage). I checked with old bearings and new ones and there was a definate difference of over .003 clearance.
Thanks guys for the comments.

 

[Pronto]

The oil pan on the Olds 307 is not designed for a high volume oil pump. It's capacity is too small. The sbo's are notorious for leaving lots of oil in in the heads. The oil drains are not cast clean and they are in an area that doesn't drain well. The oil puddles there. I wouldn't bother trying to make a race engine out of the 307 so it's not even worth the discussion of cams in it. Crane Cams though does NOT recommend a high volume/high pressure oil pump on engines that don't rev above 6500 rpm. They say it causes undue wear on the cam. Just another case of bigger isn't better especially with a stock engine.

 

[Red Regal T]

I use a Melling HV oil pump on my Red Regal T. I think my car is just getting broke in as explained in my signature. Maybe I'll have a problem, someday. HV oil pumps bad = myth.

 

[6SENSE]

These .307s are a dime a dozen as far as Im concerned. It was a shame thats what they put in the Gbody 442s & Hursts. H.O., yeah right. My brother and I had a '72 Delta 88 convertible with a Olds .350 a while back. Now that motor moved that big boat like it was nothing. Thats what should have gone in those cars not a .307. Same goes for the Monte SSs with .305s. Nice cruising engines but thats about it. Okay back to the subject............I just dont really have the $250 to spare to grab another .307 from the junkyard (good running one of course). Or rather, I felt I mise well give it a shot fixing this one before I had to opt towards grabbing another. Im not going to put much more money towards this car because I will eventually sell it. I am just getting it right before I do. Its a clean '86 Broughm so I should be able to get some decent money for it if all is right.....so I can put towards the Buick (Yeah right I wish, itll probably go towards bills , but if theres anything left it will go towards the Buick ).

Sooo, ya think Piston pin is the only other possibility for the noisy cylinder #2?