Comet Oil Filter Woes

[aldeburgh]

Thats it Peter! The only oil filter that will fit a Comet properly and actually filter the oil is a felt one (unless you are fortunate enough to have a perfectly circular centre boss , then the VOC filter might do it) The felt one has enough "give" to sit over the irregular shaped boss on a Comet and form a good seal.
Don,t know about the twins ,I am guessing they are perfect..........in every way.

 

[vibrac]

Thats it Peter! The only oil filter that will fit a Comet properly and actually filter the oil is a felt one (unless you are fortunate enough to have a perfectly circular centre boss , then the VOC filter might do it) The felt one has enough "give" to sit over the irregular shaped boss on a Comet and form a good seal.
Don,t know about the twins ,I am guessing they are perfect..........in every way.

In my opinion this should be read as "unless you are unfortunate enough" as I said before I have never found one not to fit so now I always fit the more efficient filter, the last one I had gave a warning to that end on its label.
Like everything on a Vincent of 70 years ago it wasn't made on a CAD machine ( back then that was probably an old Riley outside a nightclub) so check before fitting all components

 

[aldeburgh]

If the centre boss of my machine was perfectly round I would consider myself FORTUNATE as I would then be able to use the cheaper and probably more efficient VOCS filter ,I did check before fitting and found that it did not ,unless modified (back at this point to my original post) I am in NO way knocking the Spares Co. I just wanted a filter to fit without modification. Indeed it was my intention to hopefully warn others (I know VOCS filter has a label on it warning that modification may be required BUT you can only see this warning AFTER you have paid £5.72p for the thing) that the filter lovingly purchased and installed on the machine may not actually be performing that function.
As you rightly point out CAD was not used , it did not need to be , the pleated felt filters coped with the engine castings perfectly, the modern equivalent does not always do the same you are indeed FORTUNATE not to have had this problem.

 

[Martyn Goodwin]

Those watching my other threads will know that the big end in my Comet died - fortunatly I heard it early and there is no consequential damage. Shafts are OK as are the main bearings. With the motor out and the cases split to deal with the big end I am also going to mill the oil filter chamber to ensure that I have a central located boss of 20mm diameter and that the floor is flat to seal against the filter rubber gasket. Of course I am refering to the new paper oil filters from the spares company.

None of this precludes me from using felt filters that I may have on hand.

Martyn

 

[Martyn Goodwin]

V3 Products is now selling a paper element oil filter for a Comet that WILL fit just about any comet around. Its centre hole has been increased to a full one inch and its overall height has been decreased to 3.15 inches. So even if the centre boss inside the filter chamber is off centre it still works and even if the floor of the filter chamber has not been machined - it still works. Bonus is that the reduced height coupled with the "float" on the filter chamber end cap seal and spring means that in terms of height it works on machined or un-machined filter chambers. For more info contact V3 products - they advertise in MPH - I'm just a very happy customer. Martyn

 

[vibrac]

Well thats the forth Comet with a wide spread over the 5-6 years of production whose oil chamber I have inspected and they all had a central oil hole so the ones that are off center and need the old felt element must be rare.

 

[aldeburgh]

It is not the oil hole that causes the problem , on mine it was drilled centrally through the end of the housing , the problem is the boss through which the oil hole is drilled , this boss has a rough cast outside edge ( on mine it was roughly the shape of Australia) .
The lovely metal canister filter from VOCS would not sit over "the coastline" unless butchered , however the felt one sat over it and was" in the sea " all the way round

 

[ah_sprite]

Can't see any details in MPH - can someone direct me, please?

 

[davidd]

Can't see any details in MPH - can someone direct me, please?

Ah,

Try another MPH. I don't think there is an ad in the latest, but there should be one in the last few months with a clutch on it and an Australian address.

David

 

[davidd]

It is not the oil hole that causes the problem , on mine it was drilled centrally through the end of the housing , the problem is the boss through which the oil hole is drilled , this boss has a rough cast outside edge ( on mine it was roughly the shape of Australia) .
The lovely metal canister filter from VOCS would not sit over "the coastline" unless butchered , however the felt one sat over it and was" in the sea " all the way round

Aldeburgh,

Nicely put. I had the exact opposite problem in my racer. The boss had a large void in it all the way to hole. This void ran under the seal on the paper filter so it was feeding unfiltered oil to the crank. The problem in both cases is that the felt filter seals on their outside diameter,that is around the boss, against the wall of the chamber, while the paper filter seals on the small diameter of the tiny boss . On the twins this area of the boss seems to be fine, but on the Comets the shape of the boss is "hit or miss." Although the paper filters work on many bikes, ultimately the boss, which provides the seal, was not designed or intended to provide a seal.

It is unfortunate that the makers did not glue a large rubber ring (thicker than the boss) on the end of the paper filter so it could seal on the rear of the chamber wall per the original design. Alternatively, one could make a banjo bolt that reached further into the oil chamber that would seal on the small diameter of the paper filter.

David