Oil Pump ?

[3.8L V-8 eater]

Hi, to all

I have my motor on the stand and just put the front cover on. Next I need to put on the oil pump, but noticed that the 2 oil pump gaskets I have are different. One has the opening next to the feed line hole open and one does not

So, which do I use or does it matter???? On a side note I have done the Earl Brown mods to the front cover and this is a stock oil pump. No high volume pump with the extra plate.

I've attached a picture of the gaskets and you can see the one on the bottom is a different color and has the opening closed off where the one on top does not!!! In the picture it looks like the retangular hole next to the feed line hole is open but you are actually looking at black gasket material between the 2 bolts on the top.

Thanks!!

 

[3.8L V-8 eater]

Anybody???

 

[83ttypecooled]

Hi,
I'd use the top gasket. I don't think the cavity covered by the other gasket is an issue,but you are gonna prime this thing on the stand anyway,so if you have oil pressure and flow problems, you'll know right away. I went through my motor a couple of years back, and don't remember an issue with gaskets on the pump. By the way, on the stand, don't expect real flow up to all the valves, as I think the motors need to rotate quickly to show oil to all the rockers. I understand your concern, it's these little things that can make or break a motor very fast. Good luck with the fresh rebuild!

 

[turbobitt]

I think that large rectangular port is the main suction. Can't remember what a stock system looks like but if there is not port in the mating filter adapter then it's probably not needed.
The slot is needed to connect the drillings with the suction pump cavity during the manufacturing process.
Allan G.

 

[3.8L V-8 eater]

Thanks for the responses!! I just ordered a couple extra gaskets which were black felpro and they 2 did not have the cavity cut out... Will check the oil pump to see if theres a cavity that mates to the opening on the front cover. If so I will cut out the black gasket to look like the brown one.

 

[turbofabricator]

Use the thinnest gasket you have. Check the clearance between the pump gears and the pump cover (use plasti-gage if you don't have a depth Mike and can calculate the clearance) shoot for UNDER. 001" that's less than a thousandths of an inch. TA Performance has pump shims out of neoprene that will allow you to blueprint your pump. I shoot for. 0005"clearance. It really does make a difference. After adjusting the clearance, take a BIG flat blade screw driver and turn the pump by hand. If it is too tight, and the next thicker gasket is too thick, hand lap the gear faces (both) on a flat plate and recheck. It takes me more than 3 hours to set up a timing cover, ready to run. If you end up with. 002" clearance, it will hurt hot idle oil pressure.

 

[3.8L V-8 eater]

Use the thinnest gasket you have. Check the clearance between the pump gears and the pump cover (use plasti-gage if you don't have a depth Mike and can calculate the clearance) shoot for UNDER. 001" that's less than a thousandths of an inch. TA Performance has pump shims out of neoprene that will allow you to blueprint your pump. I shoot for. 0005"clearance. It really does make a difference. After adjusting the clearance, take a BIG flat blade screw driver and turn the pump by hand. If it is too tight, and the next thicker gasket is too thick, hand lap the gear faces (both) on a flat plate and recheck. It takes me more than 3 hours to set up a timing cover, ready to run. If you end up with. 002" clearance, it will hurt hot idle oil pressure.

This is good info!! I will shoot for a tight tolerence and make sure it's not so tight the gers don't spin.

How much do you figure the tolerence shrinks when you actually put on all the bolts on the oil pump and tighten???

Thanks!!

 

[earlbrown]

How much do you figure the tolerence shrinks when you actually put on all the bolts on the oil pump and tighten???

Thanks!!

Enough to lock the pump up a lot of the time. Have to tighten it up and take it off quite a few times to set it up right.

On your original question, that extra hole on the tan gasket really won't matter as the filter adapter is solid on that section. Normally those gaskets will lock the pump up if it's the real thin one I'm thinking it is. Go with the one that will let you set the proper end clearance.

 

[3.8L V-8 eater]

Enough to lock the pump up a lot of the time. Have to tighten it up and take it off quite a few times to set it up right.

On your original question, that extra hole on the tan gasket really won't matter as the filter adapter is solid on that section. Normally those gaskets will lock the pump up if it's the real thin one I'm thinking it is. Go with the one that will let you set the proper end clearance.

Earl your right the tan gasket is very thin. I will use the black felpro gasket and start with one to see where that gets me....While doing your mods I decided to drill the extra hole to get oil to the other side of the oil pump gears faster. This was optional but seemed to make good since :smile:

 

[buickboy]

I am dealing with an leaking issue right now with the oil pump cover gasket. The tan gasket you picture has a small hole next to the bolt at the top of the picture. Surface area there is already marginal and when a hole is in the gasket there, it will leak. use the gasket without the hole.

 

[Just a Six??]

Isn't the rectangular port on that gasket (that we dont need) for the KB setup or the Mellings plate or similar? I seem to remember a plate that had a space for it but I may be wrong? I have had KB & Mellings but dont remember what they looked like now? Long time back that I had them.

 

[earlbrown]

The rectangle hole is what feeds the filter adapter from the pump output.

If you mean the long one with the slash cut end, I think that was used with the early engines that used a different filter adapter. That Kenne Bell booster plate used that area to let oil go up and over the pump housing to feed the other side of the gears.
That hole I came up with solves both those problems and just feeds them directly.