Failed vanos test post Beisan

[JeremyJames]

Did the pistons stick during installation on the bench or was this found out after the vanos was installed that sticking pistons were the cause of your issue?
Did you also have slow vanos response times and/or fail the vanos test?

I am almost wondering if I was told the drive the car "hard" in order to wear down the pistons into their new, tighter fit holes in the new non-OE pump disc.

If that's the case I sure hope it fixes the issue as going back to an OE re-drilled disc with pistons that are worn down from the non-OE disc wouldn't good either.

Always something.

Also Icecream here is my story/video below.

https://nam3forum.com/forums/forum/main-forum/e46-2001-2006/89273-beisan-systems-faulty-product

[maupineda]

Weight changes and redrilled holes should not affect the pumping mechanism. As far as I understand, oil is pulled into the pistons as those come out of the bores and when those get compressed (the disk is off center so as it spins the pistons get pushed in) high pressure oil is shot out of the pump. Weight will affect moment of inertia, but the disk is solidly coupled to the exhaust cam. So even though holes will (very slightly) decrease the rotational inertia of the engine internals, the speed of the disk is still directly controlled by the cam speed.

The only thing that would affect pumping is what mau has pointed out. Smaller/bigger piston bores and different geometry in the veins that connect the cylinders to the pump output will definitely affect the volume of fluid that can be pumped with each revolution.

totally agree drilling two new holes wont change the performance, it is a radial pump, the weight of the disc has no impact on it.

In fact, a lighter disc would be better by reducing axial load on the pump shaft, and since the holes are in a regular patter, in fact with two new holes it will be more balanced.

[maupineda]

I had no frame of reference what was good response times when I did that original vanos test.
I simply did a full vanos rebuild because I wanted to take care of the hub tab failure issue and did the rest while I was in there kind of attitude.
Now I'll be in there again and again.

Don't feel bad, I did the same thing, but we did not know better, did we? My car at 43k miles needed nothing but driving LOL. I even did the rattle kit... typical break what wasn't broken jajajajaja

I got concerned too about that having a disc of unknow material spec (type of steel, treatment, hardening, etc, etc, etc) and what could do to the rest of the unit that I just bought a spare off of a low miler. jump to ebay and get one, rebuild it, and then swapt it when you feel like. you will learn that the car, as is, will drive fine.

The images above are from my spare unit with 35k miles, but really, even units with 60-70k miles will be good as new as long as they are not all varnished which would indicate pool oil change schedule. this pumps are like crank/rod bearings, they would last long, more so this as it is just a pump with relative low force loads as all racers are oiled. So they will last fore ever. to give you peace of mind, unless the disc is way off, your unit will be fine and an OE disc should be all you need.

to measure something like this you need special micrometer that can measure bores and diameter, ideally a CMM. but since most of us don't have access to it, sourcing an OE disc would be solution, but first measure your pressure to confirm your slow response times are related to low pressure pump.

[Arith2]

Moral of the story here. Replace the poorly engineered part, the exhaust hub. The hub doesn't affect oil pressure or any real timing, unless it breaks. Yeah the spring sits in it but no big deal. I got a VAC hub and never touched my pump disk(except removal and install, it also saw some brakleen because that stuff is essential, I may have also dropped it once or twice).

In all seriousness, it seems like we are taking much less risk when getting a hub over doing a pump disk. While it is good to save money where possible, our pump disks are not faulty. The holes were machined larger and the steel on the hub is what breaks. There are multiple ways to skin a cat. The hub is the way that carries the least risk. My hub came with thicker and larger tabs. The shape of them is also much more structurally sound. I personally don't like the idea of reusing a fatigued exhaust hub. Hardened steel isn't very resilient when it's stressed to its limit.

[Icecream]

Moral of the story here. Replace the poorly engineered part, the exhaust hub. The hub doesn't affect oil pressure or any real timing, unless it breaks. Yeah the spring sits in it but no big deal. I got a VAC hub and never touched my pump disk(except removal and install, it also saw some brakleen because that stuff is essential, I may have also dropped it once or twice).

In all seriousness, it seems like we are taking much less risk when getting a hub over doing a pump disk. While it is good to save money where possible, our pump disks are not faulty. The holes were machined larger and the steel on the hub is what breaks. There are multiple ways to skin a cat. The hub is the way that carries the least risk. My hub came with thicker and larger tabs. The shape of them is also much more structurally sound. I personally don't like the idea of reusing a fatigued exhaust hub. Hardened steel isn't very resilient when it's stressed to its limit.

Agreed. The hub could have problems with the gear meshing but my VAC unit was perfect, very impressed with the quality. A redrilled disc is good too but to your point, not a fan of putting a fatigued hub back in.

[eacmen]

I got blocked by several facebook users for arguing that the Beisan 2 hole disc was not OEM. Raj claims that the original manufacturer of the disc makes his. And my argument is it doesnt matter who makes the disc, it is Raj’s design and he needs to take responsibility for it.

I haven’t had this issue as both of my pump discs have had four holes. But the experience of some users, specifically around the four small pistons, is cause for concern and Raj may need to start making the pistons to match the pump disc instead of reusing those from the OE disc as the tolerances seem to be inconsistent.

[sapote]

I haven’t had this issue as both of my pump discs have had four holes. But the experience of some users, specifically around the four small pistons, is cause for concern and Raj may need to start making the pistons to match the pump disc instead of reusing those from the OE disc as the tolerances seem to be inconsistent.

The owner's used pistons should be smaller than the new OEM pistons, and so if these used pistons cannot fit to Raj's disc then his disc has the wrong holes, period.

[sapote]

Replace the poorly engineered part, the exhaust hub.

The stock hub has 2 problems: the tangs are little too small for the disc holes, and the tangs have sharp 90* corner at the hub base which is a stress riser. It starts cracking when the tang hammering the disc due to too much plays in the fitting.

[Cubieman]

I just hope I am not damaging my disc pistons in a tighter fit environment so when I switch to a re-drilled OE disc they are now too loose. Not to mention the springs might be getting messed up.
I feel like I need an OE disc right away and don't want to run this product in my car, but I may be getting carried away here.
I know you can't just buy the pistons/springs on their own.
If anyone has a re-drilled disc I'd be interested.

[sapote]

I know you can't just buy the pistons/springs on their own.
.

Good point. Disc/pistons and center shaft were tested and matched by the factory. I believe they are all tight tolerance to work as a high pressure pump. I bet one cannot feel any radial plays on a OE piston/hole fitting.

[Shonky]

As someone about to install a 2 hole "new" disc, this concerns me a bit and the clock is ticking if I want my core charge back - I wasn't expecting a newly made part. Ugh. Thought I was doing the right thing sorting the VANOS (throws a code every week or two)... Now have $1k of parts to decide what I'm going to do...

Are these differences in the oil piston holes measurable with regular tools i.e. a quality digital caliper with 0.01mm precision?

[maupineda]

As someone about to install a 2 hole "new" disc, this concerns me a bit and the clock is ticking if I want my core charge back - I wasn't expecting a newly made part. Ugh. Thought I was doing the right thing sorting the VANOS (throws a code every week or two)... Now have $1k of parts to decide what I'm going to do...

Are these differences in the oil piston holes measurable with regular tools i.e. a quality digital caliper with 0.01mm precision?

NO! you are talking *0.xxx of a mm. that is the tolerance range for engine components. you need lab equipment, like Mitutoyo micrometer for diameter and bore.

send back the disc for a refund, and have a machine shop drill you new holes, or use the refund and get a new hub and leave the disc alone

[AK72]

Guys here is two BMW OEM discs that have two different sizes now think about swapping them from one VANOS to other will they perfect match with the shaft holes the answer is NO they will never!!!
So donor disc is BAD very BAD Idea for your VANOS.
I drilled my original disc by myself - https://youtu.be/cFZ3W5BS_R8

[Cubieman]

Fuck, I sure hope this doesn't end with me having to buy a brand new vanos to make it right.

[sapote]

Guys here is two BMW OEM discs that have two different sizes

Disc thickness is not a design critical dimension, because the disc is floating axially due to the pistons are running on the big circular roller bearing.