High Volume Oil Pump Warning

[graeme]

This is a warning that could have cost me a lot more than it did,,,,,
I fitted a high volume oil pump to my 450 and ended up destroying the pumps backing plate as the new oil pump was 3mm longer than the original Ducati pump.
When I fitted the timing cover the new pump's 8mm shaft shoulder pressed against the drive gear and pushed the pumps gear into the backing plate and sent metal shavings through the oil.
The tang on the new pump is 8mm x 3mm (but is 3mm longer)
I am a dickhead for not checking this before I fitted something that wasn't standard.


The damage



I then contacted the supplier and asked about the extra 3mm, I was supposed to remove a mm from the drive gear but that part was lost in translation.
This is totally my fault and I do not hold the supplier responsible in any way,,,, I should have checked the clearance.
I relived the drive gear and 1mm and fitted the pump and timing cover and measured the clearance through the right main bearing while the cases were apart.


I have since spoken with Mr Lacey ('THIS IS NOT HIS OIL PUMP") to warn him of this, but as I should have known he was aware, and supplies his own pumps to overcome this.
I'm sure Nigel will be ok with me pasting his response here to warn others and also offer some valuable advice regarding larger volume pumps.

Graeme

Nigel's response below,,,,

[graeme]

Hi Graeme

Sorry to hear of your woes, Thank you for thinking of me and private messaging me first rather than posting it publicly. Sometimes products can get a bad name for no good reason and no matter how much you try to explain, sh** sticks! I have known of this for more than 15 years and have been amazed at how most suppliers don't tell their customers! We have always informed our customers of the modifications necessary with a leaflet included with the pump and we also have the same written guidance on our site. Maybe your case was an unfortunate language failure.

http://www.laceyducati.com/ducati-parts ... p-291.html

We have our pumps specifically manufactured for us which vary slightly from the normal available. Ours have the oil pressure relief as original to avoid too much pressure especially when cold with thick oil. We also modified our pumps to only about 22% extra volume as we thought the higher volumes were unnecessary and in theory potentially detrimental to the big end. There is a balance between getting as much oil as possible to the head for lubrication and cooling (as long as it will drain out quickly enough) and not too much oil to the roller bearing. That said, I personally have not experienced any problems with the higher volume pumps, apart from oil leaks from some cam end covers. This is over many years of hard race use on short circuits and the IOM.

Your modification of the drive shaft is not my preferred way of doing the adjustments. A lot of the advantage of the new pumps is the use of an 8mm shaft which allows a narrower 3mm drive tang. There is normally a horrible misalignment of the driving gear and oil pump which can cause the two to bind together solid when rotated. The slot is 4mm wide and the original drive tang is 3.5mm wide, so you can see from this how bad the misalignment is! With the 3mm wide tang they never bind and not with great surprise, the oil pump bushing does not wear out. If you ever wondered why the oil pump bushing on the original pump wears out so badly, now you know

Back to your mod, if you reduce the slot depth potentially you can end up with the end of the tang in the radius of the slot reintroducing the problem. As long as the flat face of the tang is driving on the flat face of the slot then it will be fine. To this end the best way to resolve the problem is to press the shaft through a little bit to provide clearance. That way you maintain the flat to flat drive and in fact extend the support of the shaft fractionally. Only one caution here, is to ensure that the end of the shaft cannot come into contact with the crank or crankpin as I have seen. If that is the case it is just necessary to trim a bit off the end of the shaft to ensure there is one mm or so clearance.

Hope this helps and if you wanted to flag it up on the forum, that may be a good idea s you do not want others to make the same mistake. If you want to include any of this in your post, including the link on our site, that is also fine by me.
Have you got to the bottom of why your piston seized, what piston was it, was it one of ours? If you let me know more details with things like clearance, ring gaps etc, I may be able to give you a second opinion.

Best Wishes
Nigel

[Eldert]

Hi Graham

about the piston seizure . most off the time a piston nips up on the thrustface

your piston nipt up at the cilinder head bolts . how much torque did you use for the cilinderhead bolts ?

Regards Eldert

[graeme]

Hello Eldert,

Tight but not too tight. I use a standard spanner, not a socket with a long handle.
Please explain.?
It looked as if metal shavings from the oil pump backing plate had come out the oil holes under the oil rings and caused the nip up?
The marks are under the holes in the piston. (this is the inlet side of the piston, no marks anywhere else on the piston)
There was metal swarf in the head rocker area and in the sludge trap in the crank. Very little anywhere else.

Graeme

[Eldert]

Hi Graeme

if you torque the cilinderhead bolts to much the barrel wil distort and you will get the same scuff marks as the lefthand one on your piston .

Eldert

[graeme]

I understand, what do you torque your head bolts to?

[Eldert]

i use less then workshop manuel specs . i looked at the Clymer manuel and they say 3.4 to 4 kgm .

i use 3.2 kgm and do it in a few steps

is it one of Carlo oilpumps ?

Eldert

[graeme]

Been quiet on here lately,,,,,, so,

I've been riding this bike to work for a couple of weeks now and it runs very well with no oil leaks.
Today I noticed oil dribble being blown (by the wind) back onto the left side cover, coming from the O ring at the head to cylinder. Not much but I haven't had a leak there before.
This is proving Nigel to be correct.
As this oil pump doesn't have a pressure relief, what are the chances of machining a groove to the pressure relief and curing the oil weep?

Graeme

[LaceyDucati]

Graeme

If you want to use the relief valve, it's just a matter of milling a 4mm wide 4mm deep slot as per the original pump. Just ensure you remove any burrs kicked up, by flatting the face. Your pump body looks a bit thin compared to most, but I can't see it causing a problem. I've done a few pumps like this.

Regards Nigel