Tin Indian

I posted this before, but people seem to post here daily about erratic or fluxuating oil press after a cam change, so, here goes again >

This won't help a car with a frozen relief valve in the pump, but I feel it will elliminate the O ring sealing problems that plague so many people here.

I was in the same boat as many of you. I was [ABSOLUTLY] sure I installed my oil pickup tube O ring properly. Well, I had fluxuating oil pressure and little if any oil coming up through the rockers along with clattering lifters after prolonged idle. No doubt in my mind that I had an O ring problem. I pulled it back down only find that the O ring was missing! I KNOW I installed it properly on the tube prior to bolting the tube up to the pump. Where the hell did it go! Replaced it with a new O ring and everything was fine thereafter.

Ok.... If I was to ever remove the pump again, I would make a gasket to fit between the pump and pickup tube. Get some gasket material avail from any auto parts store. Using the oil pump as a guide, draw your lines on the gasket material. Of coarse, cut the hole out in the center and a small hole for the bolt. Take your time, and you can make a gasket that looks like it came from GM.

Use the O ring, but additionally, use this gasket between the pump and flat surface of the pickup tube. I am convinced that you will never have oil pressure problems associated with the O ring. After all, the reason a missing, misaligned, or torn O ring causes oil pressure problems is that the mating surfaces of the pump and the pickup tube are located above the oil level in the crankcase, and what happens is that you start sucking air where the two parts join. A gasket will prevent any sucking of air at this mating surface.... period!

It is just >NO FUN< to have to pull the front of the motor back down after all the work you put into it. And then you think to yourself; I remember how good my oil pressure was before started this cam change! Jeeez!

I am suprised none of these "Tuner Shops" that advertise on this board have not made up a bunch of gaskets and started selling them. I can promise you that they would sell a gasket to 98% of the folks on this board that is about to change out a cam and chain. BTW, anyone that wants to sell these has my permission. I don't have any rights to it
Cheap insurance if you ask me....

And, I am convinced that there are no negative drawbacks using an oil pump / pickup tube gasket.

Just my opinion,
Ron

Tin Indian

And I can tell you whats almost sad for me to say;

Since reading so many of these oil pressure related posts, I seem to look at my oil pressure gauge as much as I scan my speedometer while driving. This is the only car I have ever owned, that I have shown this strange behavor pattern.

Cal

iTrader: (1)

OK I'm getting ready to install a new oil pump along with a cam, but I'm still waiting to hear what's so bad about the stock oil pump?

Tin Indian

I think the stock oil pump's gear design is great. I have never heard of one failing. What seems to fail is the pressure relief valve. The so called "ported pumps" are lightly machined in the bore area that the pressure relief valve slides in. This keeps the relief valve's "piston" from jamming in the bore.

Other than that, the real problem is with the poor design of the pump to pickup tube. The O ring that seals this area does not fit into a machined groove. That's the problem. And a gasket will fix it. Also remember, there is no pressure in this area (just suction), so the gasket will never "blow out".

robertbartsch

I was a tranny builder in my past life and all the seals in a tranny have a grove to hold the o-rings....a GM bad design here in the oil pump...

The O-rings that are gone do not dissapear like magic ...they work up and off of the tube while the bolt is being tightened,,,,, when you start the motor they get sucked into the pump gears where they are forever mashed into little pieces...

The gasket idea sounds good to me...

Why hasn;t anyone made these for resale; It is sorta like a catch can.... i made one of these from 2" pvc pipe this weekend and it works great, i keep thinking ...why doesn't anyone sell these???

robertbartsch

Oh, one more thought on the gasket idea...

...it may not work, since the tube is held against the pump by a single bolt....

L-EATER

iTrader: (2)

The only way a gasket would do anything is if you weld the pickup tube to the retaining flange. Otherwise it could still suck air around the tube. I have been studying this all day-my new pump will be here tomorrow and I want this to be the last time I work on it for a while.

Ebbsnflows

iTrader: (15)

LOL...I thought I was the only one that does this!

Viper

iTrader: (6)

Me too - especially since I lost my motor last year and now have a new one due to the relief valve sticking open.

Cal

iTrader: (1)

Right on . . . I'm in the same boat: pump on the way and want to make sure I get it done right. I wonder if machining a grove for the O-ring would help; I have a lathe. I also have a welder, but I assume there must be a joint there to allow disassembly or it could be sealed with a weld bead all the way around it. Has anyone tried red RTV to seal it?

L-EATER

iTrader: (2)

I got my crap running today! I didn't want to wait on redesigning the pickup so I just slapped it together with a new pump and a new o-ring. The new pump from GM looked like it had seen better days so I took it apart and checked the valve and it was STUCK! After performing some backyard machine work on it I feel comfortable that the oiling problems are now over.

My take on the real fix for the O-ring is this: 1)Weld the tube to the flange 2)weld another "ear" to the flange opposite the bolt hole so as now you have enough meat to drill another hole to line up with the other threaded hole on the bottom of the pump 3)make a gasket and install the parts and sit back knowing you built something better than the GM engineers. I intend to get a new pickup and do this so it will be ready next time I have it apart, but I had to get it together today so I can go back to work.

Tin Indian

ttt

Ditch Digger

About a month ago I installed the following items in my motor: TEA heads, ASP crank pulley, Thunder Racing ported oil pump and a Rollmaster double roller. After starting my car I noticed that the oil pressure was 40 psi cold idle and only 20 psi hot idle. I had been worrying about the low oil pressure ever since, so this morning I decided to take the pump back out and check to see if the o-ring was damaged. To my surprise, the o-ring appears perfect but I replaced it with a new one any way. This time when I reinstalled the pump, I smeared some RTV on both sides of the one oil pump spacer that oil passes through. Well, to make a long story short, the motor now maintains about 42 psi warm idle which is double what it did before. I suppose it is possible that the initial o-ring had some damage to it that I couldn't see, but I am inclined to think that the RTV was the cure to my problem.

Cal

iTrader: (1)

Thanks for the tip, Ditch Digger. I'll be doing a cam and pump swap soon, and was thinking about putting som RTV on the o-ring to hold it in place. I think I'll put it on the spacer also as you suggest. BTW, what a nick-name, I did quite a bit of ditch-digging when younger but I'd like to forget that!

DaleMX

iTrader: (4)

That is recommended in the Rollmaster installation instructions to prevent weeping from the spacer.

L-EATER

iTrader: (2)

I put in a new pump and o-ring on Tuesday and I have driven about 300 miles since. I made 4 passes at the track Thursday and everything has been A-OK. Tonite I was racing a buddy who just bought (like a few hours ago) a Whipplecharged GMC. We went from a roll twice up to about 90 and from a stop up to about 90 then drove about 4 miles to my shop. When I pulled in I noticed the oil pressure on the edge of the red. I shut it off, checked the oil level which was fine, then when I started it back it has 0 oil pressure!!! Someone better help me fast or theres gonna be a fire!! This is absolute crap! What causes the oil pump valve to stick and how do you keep it from doing it? And before anyone asks, yes I blew my buddy completely in the weeds. That was the only good thing about this evening.

bdawg/98mechamta#9

ME TOO !

Cal

iTrader: (1)

Sounds like it might be a good idea to solder a small strainer over the inlet to that relief valve . . .

C_Williams

Usually, the plunger (valve) is hung open when debris gets stuck between the itself and bore in the housing. The worked-over pumps have the passageway and plunger "clearanced" and that seems to help.