GB Billet Oilpump Gears
#182
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They wern't ran in a car, but they are exact duplicates, we cmm'd another gear which reads down to .0001 as an additional precaution and we were provided files from the forum and they matched within thousands. A procedure like that would of added another month to the group buy atleast.
I also don't like the term "sell" perhaps passed along is the better term.
These are RC 16. Which is quite a bit higher then stock, but doesn't go into a dangerous RC that could wear the housing prematurely. For that reason durability should be extremely high. The originals did not go into the RC hardness range as I've been informed by loki.
We also spec'd the side to side clearance at .0033 in the 94-97 housing. I found my notes from the machinist. All the gears should be +/-.0005 of that.
I also don't like the term "sell" perhaps passed along is the better term.
These are RC 16. Which is quite a bit higher then stock, but doesn't go into a dangerous RC that could wear the housing prematurely. For that reason durability should be extremely high. The originals did not go into the RC hardness range as I've been informed by loki.
We also spec'd the side to side clearance at .0033 in the 94-97 housing. I found my notes from the machinist. All the gears should be +/-.0005 of that.
Last edited by TravisR; 11-02-2008 at 01:52 AM.
#183
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I also have an easy solution if the side to side clearances come out to be wrong on certain years, so don't anyone get worried. I can make a new back plate to the oil pumps that steps down slightly in the housing so that we get the correct clearance. It should be a very cheap fix, but lets see what happens.
#185
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Ok, back from... well, I'm back.
No bad reflections on you at all, Travis. The housing doesn't seem worn all across, but there is some uneveness to it.
I would think I could machine down a channel in the back plate or off the pump housing itself to bring it into spec.
Anyway, I'll go make some measurements. I highly doubt it's a defect in manufacturing, all I can think is that they went to a bigger pump in later years?
More pics and measurements to follow. They are all Harbor Frieght tools, so don't trust the absolute numbers, but repeatability and relative measurements have always been dead on with these.
More to follow within the hour. Right now I just want to figure out which housing to use, so I can put the OTHER one together in OEM configuration for my backup motor. Stupid rain. :-)
No bad reflections on you at all, Travis. The housing doesn't seem worn all across, but there is some uneveness to it.
I would think I could machine down a channel in the back plate or off the pump housing itself to bring it into spec.
Anyway, I'll go make some measurements. I highly doubt it's a defect in manufacturing, all I can think is that they went to a bigger pump in later years?
More pics and measurements to follow. They are all Harbor Frieght tools, so don't trust the absolute numbers, but repeatability and relative measurements have always been dead on with these.
More to follow within the hour. Right now I just want to figure out which housing to use, so I can put the OTHER one together in OEM configuration for my backup motor. Stupid rain. :-)
#186
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Abe, on another note, anything special (gear pullers, etc) I'll need to install these? I am assisting on an install this afternoon (motor is out of the car). Just curious as to what I need, what tolerances I need to check.
#187
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Ok, well, these are just measured off what I had laying around, so it might not be "factory spec" but here's what I got:
B.E.
Outer Gear Thickness:9.33
Inner Gear Thickness:9.35
Outer Gear OD:78.88
OEM 2000 (used)
Outer Gear Thickness:9.41
Inner Gear Thickness:9.42
Outer Gear OD:78.86
OEM 2003 (2001?) (used)
Outer Gear Thickness:9.91
Inner Gear Thickness:9.92
Outer Gear OD:78.86
The pumps are different! The whole detail around the pressure regulator, and the depth of the step in the cap are different.
I would imagine they "beefed up" or maybe added better control in the oil pump for VVT.
Pics:
![](http://abefm.smugmug.com/photos/408327527_P5d4M-L.jpg)
This is the VVT gear in the 2000 housing. Clearly it's too large.
![](http://abefm.smugmug.com/photos/408327492_GQPGN-L.jpg)
The cap for the oil pumps, late model on left. Upper right corner you can see the different shape. It's deeper, too, but you can't tell in the photo as well.
![](http://abefm.smugmug.com/photos/408327274_FkkHu-L.jpg)
VVT oil pump. Casting mark of D-2 visible upside down on left.
![](http://abefm.smugmug.com/photos/408327422_t2Z7L-L.jpg)
2000 oil pump. Casting mark is different, not visible, says D-4. Odd the newer pump has the lower number, might just be a date code.
There's the SLIGHTEST chance I got them confused, but I don't think so. Mine's all clean and perfect. For all the abuse my motor gets it really looks good.
B.E.
Outer Gear Thickness:9.33
Inner Gear Thickness:9.35
Outer Gear OD:78.88
OEM 2000 (used)
Outer Gear Thickness:9.41
Inner Gear Thickness:9.42
Outer Gear OD:78.86
OEM 2003 (2001?) (used)
Outer Gear Thickness:9.91
Inner Gear Thickness:9.92
Outer Gear OD:78.86
The pumps are different! The whole detail around the pressure regulator, and the depth of the step in the cap are different.
I would imagine they "beefed up" or maybe added better control in the oil pump for VVT.
Pics:
![](http://abefm.smugmug.com/photos/408327527_P5d4M-L.jpg)
This is the VVT gear in the 2000 housing. Clearly it's too large.
![](http://abefm.smugmug.com/photos/408327492_GQPGN-L.jpg)
The cap for the oil pumps, late model on left. Upper right corner you can see the different shape. It's deeper, too, but you can't tell in the photo as well.
![](http://abefm.smugmug.com/photos/408327274_FkkHu-L.jpg)
VVT oil pump. Casting mark of D-2 visible upside down on left.
![](http://abefm.smugmug.com/photos/408327422_t2Z7L-L.jpg)
2000 oil pump. Casting mark is different, not visible, says D-4. Odd the newer pump has the lower number, might just be a date code.
There's the SLIGHTEST chance I got them confused, but I don't think so. Mine's all clean and perfect. For all the abuse my motor gets it really looks good.
#188
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![](http://abefm.smugmug.com/photos/408336939_fWGkr-L.jpg)
![](http://abefm.smugmug.com/photos/408336964_S3M3z-L.jpg)
I'll probably go to hell for publishing this stuff. You'd all better go to my trial as character witnesses.
higher res pics available here:
AbeFM : photos : Oil Pump Specs 2000- powered by SmugMug
Right now I'm worried, if I put together this 2000 oil pump with a 2001 head, will I have issues with VVT? I don't want to have to pull this motor back out just to get it's crappy oil pump in my "good" motor.
Matt - or anyone - do you have the specs on the oil pressure or the regulator on the VVT cars?
#190
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The bigger difference is the housing, I would think the bigger gaps on the side might mean higher pressures? Certainly the regulator is designed to blow off a lot more oil! Perhaps overpressure is bad for the VVT set up.
Also, the gear is different inside - the corners have that "actually machined" reliefs in them. That's on purpose, right? Guess I should check the width there.
Also, the gear is different inside - the corners have that "actually machined" reliefs in them. That's on purpose, right? Guess I should check the width there.
#192
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This is all really interesting, because this is what we found when we were working on these. The 1994 housing was running interference at its installed height. There was literally 0 clearance, and if I remember correctly that accurately reflects the difference in your measurements between the 2000 gears and the BE variant. So are we dealing with 3 different sizes so far? 94-97, post 97 and pre V.V.T., and Post V.V.T.?
We need a couple of more people to report back and see what they found on clearances. You should be able to get away with .008, but if you go wider then that on side clearances you need to think about your oil viscosity, or a fix to the problem. You can think of those side clearances as being "dynamic" in how thick of an oil you use in that clearance. Mazda recommends a range of viscosity, so if I can calculate what the relative thickness would be I can tell you guys what clearances are really allowable. In their view they had to accommodate poor oil quality of the late eighties early nineties, and much more unstable viscosity so its likely these clearances are heavily skewed towards the tight end of things.
On pump output, its going to be the ratio between the heights. So right around 5%. I don't think that would make enough difference. We are talking about such a small amount of volume increase at 5%. That has to be on the order of 5mm^3 or a good fat drop of something every rev.
We need a couple of more people to report back and see what they found on clearances. You should be able to get away with .008, but if you go wider then that on side clearances you need to think about your oil viscosity, or a fix to the problem. You can think of those side clearances as being "dynamic" in how thick of an oil you use in that clearance. Mazda recommends a range of viscosity, so if I can calculate what the relative thickness would be I can tell you guys what clearances are really allowable. In their view they had to accommodate poor oil quality of the late eighties early nineties, and much more unstable viscosity so its likely these clearances are heavily skewed towards the tight end of things.
On pump output, its going to be the ratio between the heights. So right around 5%. I don't think that would make enough difference. We are talking about such a small amount of volume increase at 5%. That has to be on the order of 5mm^3 or a good fat drop of something every rev.
#193
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0.008" where? on the side of the gear?
I have 0.008" (right at the wear limit) on the outter edge of the gear diameter, which worries me a bit, and 0.005" on the side, which also worried me.
I get 0.020" difference between the gear thicknesses, which is also what I got when I measured the clearance (self consistant).
All I can say for sure is there's a difference in the 2k1 and up relative to the 99-00.
Interestingly, there's plenty of leak in the (well in spec) 2003 stock set up I just reassembled. It's a ~0.004" gap, and blowing air through it even under relatively low pressure had oil bubling out all over the place.
I have 0.008" (right at the wear limit) on the outter edge of the gear diameter, which worries me a bit, and 0.005" on the side, which also worried me.
I get 0.020" difference between the gear thicknesses, which is also what I got when I measured the clearance (self consistant).
All I can say for sure is there's a difference in the 2k1 and up relative to the 99-00.
Interestingly, there's plenty of leak in the (well in spec) 2003 stock set up I just reassembled. It's a ~0.004" gap, and blowing air through it even under relatively low pressure had oil bubling out all over the place.
#194
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Oh yea definitely. That's not really a good test though, because that takes into account surface tension and viscosity. Also the entire cavity would be filled with oil in actual operation.
In clearances I was talking about the width. The OD gear fit to I.D. of housing I made purposely on the outer limit so that there would be more cushion in the bearing. All that basically is is a big journal. It should increase pump efficiency a smidgen, as R grows the stress tensors get smaller in between each fluid element as you move radially. (so we have relative velocity difference between each radial element being smaller, so viscous drag between the elements is reduced) So less fiction work is performed. It also acts as a better shock absorber to vibration loads. As r gets really small the force gets extremely large on the pump to recenter. The slightly wider clearance is like throwing softer shocks on the car, there is much less instantaneous acceleration on the parts to recenter, so less clanging of things when the bearing over compensates.
I wanted to add that the reason there is a max wear parameter is because there is a point at which the fluid region becomes turbulent and that actually increases drag. We're either right in the middle or just a bit to the right.
In clearances I was talking about the width. The OD gear fit to I.D. of housing I made purposely on the outer limit so that there would be more cushion in the bearing. All that basically is is a big journal. It should increase pump efficiency a smidgen, as R grows the stress tensors get smaller in between each fluid element as you move radially. (so we have relative velocity difference between each radial element being smaller, so viscous drag between the elements is reduced) So less fiction work is performed. It also acts as a better shock absorber to vibration loads. As r gets really small the force gets extremely large on the pump to recenter. The slightly wider clearance is like throwing softer shocks on the car, there is much less instantaneous acceleration on the parts to recenter, so less clanging of things when the bearing over compensates.
I wanted to add that the reason there is a max wear parameter is because there is a point at which the fluid region becomes turbulent and that actually increases drag. We're either right in the middle or just a bit to the right.
Last edited by TravisR; 11-02-2008 at 09:20 PM.
#196
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From what I can see its the years that are V.V.T. that there is a problem. If any of those people have issues send the gears back to me. I think I can get him to just trade me. Obviously people with earlier years are going to buy them sooner or later, and he can cut me some gears that are a little thicker, I'm pretty sure he's got the stock sitting to do that.
#197
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Gotcha.
There seem to be a lot of people wanting gears, so you could prolly just sell those, recut some for the vvt cars and not loosing anything at all except on a bit of shipping.
Thanks for the very quick response.
There seem to be a lot of people wanting gears, so you could prolly just sell those, recut some for the vvt cars and not loosing anything at all except on a bit of shipping.
Thanks for the very quick response.
#198
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From what I can see its the years that are V.V.T. that there is a problem. If any of those people have issues send the gears back to me. I think I can get him to just trade me. Obviously people with earlier years are going to buy them sooner or later, and he can cut me some gears that are a little thicker, I'm pretty sure he's got the stock sitting to do that.