gerotor front cover update

[Alky V6]

I hope I'm not being the fly in the ointment, but I have a few practical questions.

What would the advantage be of the pump being in the cover, over the installation of an external pump like a belt driven drysump or wet sump pump?

In the case of an engine failure where trash ended up going through the pump and taking it out, are we talking about having to fab up another complete cover? Seems like a lot of work.

I have done my share of custom fabricating, and after you've done enough of it, you start to realize that if an engine failure takes out that work of art, you're going to be spending a lot of time replacing that part or developing an easier, quicker solution to replacing that part.

Just looking at the future circumstances of maintenance and repair of such a specialty item.

My first question is serious. If someone does see the advantage, I'm eager to learn.

 

[GARY HARVEY]

Advantage of a Gear Rotor

Far as design, it's a idea that has been proven over the years and is in current production use for those advantages. "A better mouse trap".

Clyde Vickers sells a inline screen that fits very nicely for the suction side of whichever pump system being used and a tattle tale screen could also be used atop the oil filter to help save the pump.

Also keep in mind, the actual gear rotor parts of the assembly can be replaced should they be wiped out unlike the current cover.

I understand your thinking it may be overkill Don... and it may.

I'm not a big follower of dry sump systems for a less than all out race car. (I've got a dry sump setup and decided not to use it). Turbo Buicks are complicated enough without them IMO.

 

[Alky V6]

Far as design, it's a idea that has been proven over the years and is in current production use for those advantages. "A better mouse trap".

Clyde Vickers sells a inline screen that fits very nicely for the suction side of whichever pump system being used and a tattle tale screen could also be used atop the oil filter to help save the pump.

Also keep in mind, the actual gear rotor parts of the assembly can be replaced should they be wiped out unlike the current cover.

I understand your thinking it may be overkill Don... and it may.

I'm not a big follower of dry sump systems for a less than all out race car. (I've got a dry sump setup and decided not to use it). Turbo Buicks are complicated enough without them IMO.

I understand the gears can be replaced. What about the pump pocket cavity itself? Isn't it machined as part of the timing cover or is the pocket alone replaceable? I understand the use of pre-screens, I use them on my drysump system. They are usually coarse so that pump efficiency isn't affected. Many are designed only to catch the big stuff. It's the fine grit floating around in the oil that does most of the damage, if not found out quick enough. Other than convenience of installation and cost savings for the big manufacturers, what other performance advantages might there be? Curious George here.

 

[JayC]

Ive been begging someone to make this for years.. in fact, Kendall built his after I told him about it. I really, REALLY wish someone would step up and make this thing available. It's far superiour to anything else out there.

 

[GARY HARVEY]

Any problem having a replaceable sleeve for the rotor?
Check it out, nothing to loose. I don't see why it couldn't be fitted along with the balance/rest of the change.
Last time I scattered a motor, the biggest pieces would pass thru a 12 guage
and i didn't have much concern for the pump at the time.

 

[Alky V6]

Any problem having a replaceable sleeve for the rotor?
Check it out, nothing to loose. I don't see why it couldn't be fitted along with the balance/rest of the change.
Last time I scattered a motor, the biggest pieces would pass thru a 12 guage
and i didn't have much concern for the pump at the time.

As long as the facing surfaces don't get scored up too (and they usually do), I see no problem with a replaceable sleeve.

In a flat tappet application where a lobe starts to go away and untold miles is put on the engine before the problem is identifed, I see a pump replacement being needed. I for one, would not look forward to fabbing up another custom cover. It may be loads of fun the first time making the cover, but after that, nahhh. It sounds like a part that would be in as much demand as the stage II timing cover. Nice novelty item, but not one I would want to fork out R&D time and money for, in the hopes of selling a few units.

What about ease of maintenance for such an item too. An external pump is right there. Questions about the pump condition and I have to remove the timing cover? Sorry, but that is the one job on a car I dislike the most.

Are there any real performance advantages, in terms of HP, to such a pump?

 

[JayC]

If there are any performance advantages, Id imagine they'd be minimal.

HOWEVER, it would solve the dismal idle oil pressure issue on the production motors, not to mention the cam sensor housing wear issue from the oil pump pushing up on it.

I disagree about it being a novelty item. I think it would be a "go to" item if someone was rebuilding their engine and it was affordable. I dont know if youve ever seen the oil pressure on a FWD V6 but they usually idle about 50-60 PSI.

 

[Alky V6]

If there are any performance advantages, Id imagine they'd be minimal.

HOWEVER, it would solve the dismal idle oil pressure issue on the production motors, not to mention the cam sensor housing wear issue from the oil pump pushing up on it.

I disagree about it being a novelty item. I think it would be a "go to" item if someone was rebuilding their engine and it was affordable. I dont know if youve ever seen the oil pressure on a FWD V6 but they usually idle about 50-60 PSI.

I must agree with you Jay on the comparison with the stock setup. But there are already options available to mount an external pump that is much easier to install and replace, if there is the need for whatever reason.

In an application for an engine that will most likely see 100,000 miles between needed freshening, I can see the advantage. In a pure racing situation where things just plain break or wear out at more regular intervals than anyone likes to see, and regular maintenance and inspections are a way of life, I feel a different, more serviceable option is needed.

I'm not trying to 'po' anyone. I just want to present a practical, 'other view' to this discussion.

 

[Chuck Leeper]

Unfortunately...

"A better mouse trap", ultimately leads to smarter mice.

 

[Alky V6]

A side note to the subject. And I think this has been discussed before. There is a needle thrust bearing, common in the trans business, that can easily be adapted to the cam sensor to eliminate the stock thrust washer wear problem. It works great. The gear wear problem is another issue though.

 

[GARY HARVEY]

Per the FWD Buick

My wife's 91' GS with 120K idles at 40 psi (hot) and 50+ @ speed, very stable press. with less than a 10 psi change from idle to whatever, sewing machine smooth. I wish my Regal did as well...

 

[Turbo1dr]

If engine failure causes enough metal to trash the gerotor pump and cover then it's enough to trash an external rwd cover also. So either way you're going to have to buy another cover. Yes, the covers will wear because it's made like a transmission front pump assembly.

The differences I seen going from a stock pump to a gerotor pump is minimal when it comes to oil pressure. At hot idle my pressure was 18-22psi. Running at highway speeds it's about 47-50psi at 2200 rpm. Cold start-up it goes to 80psi...BUT it's not wearing out the cam/cam sensor gears, the thrust surfaces of the cam and block and it's not putting a load on the timing chain and gears like the stock pump will on cold start-ups. That's the only reason I gone through the hassle of building it. IMO, if you guys think you're going to get hot idle oil pressures of 40 psi I think you're going to be dissappointed with the 109 block. If there could be a design that allows use of "vanes" like a transmission pump then I think you could have 60psi oil pressure at idle.

IMO and off topic, I think the oil pressure sending unit should be located at the rear of the engine on the drivers side oil galley. Right now it's located where the pressure is the most...before it makes it into the block. Noisy hyd lifters at idle on a GN engine is probably due to very low oil pressures in the lifter oil galley even though oil pressure is good at the front of the block. Hope that made sense.

 

[ijames]

I think not having a belt that can break or get thrown or knocked off would be nice insurance. Rich Rezes slung off his alternator belt on his first launch this morning and I was wracking my brain trying to remember if he had an external oil pump or not, and hoping that if he did, that wasn't the belt the starter walked over and picked up. Also, Don, if the cover could be sold for say $150-200 so it's only double a normal high volume cover it wouldn't be so bad to replace it on an engine blowup (assuming it was for sale), and that in turn will help keep the sales volume up and keep them available . Now if you could just figure out a way to put a hole in it so the cam end play could be checked with the water pump in place, that would be just fantastic for all of us that set roller cam end play by shimming off the cover.

 

[ijames]

IMO and off topic, I think the oil pressure sending unit should be located at the rear of the engine on the drivers side oil galley. Right now it's located where the pressure is the most...before it makes it into the block. Noisy hyd lifters at idle on a GN engine is probably due to very low oil pressures in the lifter oil galley even though oil pressure is good at the front of the block. Hope that made sense.

I agree. I saw the bearings from a motor that spit out the driver's side gallery plug into the timing chain which chewed it up and put it in the pan. Every main and rod bearing was showing copper and the crank needed turning since the owner kept driving it for a few hundred miles while trying to diagnose his low oil pressure. According to his gauge in the stock sender location he still had a few psi hot idle and I think 30+ at 3000 rpm, with the plug completely missing.

 

[SloGN]

Guys

What i would see being a problem is that when using the gearotor oil pump set-up is that when using that pump on a higher rpm engine is that you woild cavitate the oil pump due to a flow problem to the pump. If the caviation was severe enuff it could lead to oil pump failure also. this is soemthing to thin about.


gearotor pump is turning at crank speed vs the stock oil pump thats driven on the cam @ 1/2 the speed one would see a diffrence in oil pressure at idle.

 

[Alky V6]

All very good points. I missed the pump speed deal, but if the pump volume (pump dimensions) was adjusted to the operating speed, it should work.

 

[Awesome T]

Don't overlook Turbo1dr's accomplishments

Hi Guys,
There are a lot of good points being made here as to the feasibility and ease of replacement of this pump application on a TurboBuick. But, Turbo1dr has had his on his car for two years and 14,000 miles. Last I saw his car was running 10s on its way to 9s. Enough proof for me. I think Turbo1dr has some improvements he would make to his next design, but it sounds like the mousetrap has been built and proven (GM and Turbo1dr). Now we need a manufacturer.

 

[JayC]

Guys

What i would see being a problem is that when using the gearotor oil pump set-up is that when using that pump on a higher rpm engine is that you woild cavitate the oil pump due to a flow problem to the pump. If the caviation was severe enuff it could lead to oil pump failure also. this is soemthing to thin about.


gearotor pump is turning at crank speed vs the stock oil pump thats driven on the cam @ 1/2 the speed one would see a diffrence in oil pressure at idle.

Ruggles used to use them on 10.00 Stage 1 engines if you could afford to buy one. He got about $1000 for the oil pump setup.

 

[SloGN]

Ruggles used to use them on 10.00 Stage 1 engines if you could afford to buy one. He got about $1000 for the oil pump setup.

sweet didn't know that



I wonder what he done to the inlet(suction side) of the pump to help the cavitation issues. I really think that the stock gn oil pump has problems as well.

 

[MAX PSI]

Gary, Im not easily impressed, but that is great!!! Now you guys got me thinkin!!! and thats not good Thanks for sharing all your hard work
for the rest of us to see. Thanks Mike

Its got me thinking also. I had some cam/dist gear problems to the point that it cost me a win in the finals. A dry sump in TSM is prohibited and an external wet sump would be hard to package running it off the single belt that drives everything else. (also per the rules). This cover/pump would solve my problems.
I have a couple of ?s I'm assuming the open end on the bottom left is where the filter adaptor goes. Could you add a plate there to use an external suction? Or are the cavities for supply and return to the filter?