English French German Italian Spanish

Late ES2 oil pump

Submitted by grant_tiller on Wed, 07/11/2012
Forums
Singles

Hi all - great news that the site is back up and running... amazing how much you miss something when it's not there!

I have a 1961 ES2 (62 model year)Does anyone know if the oil pump is the same as on the Dommie/Atlas?The pics look identical from what I can see. Did Norton change things for the late ES2 models, to come in line with the twins?

Thanks for your help!

Submitted by dominic_gomes on Wed, 07/11/2012

Permalink

The part numbers (old numbers) differ by one digit (15522 for the twins and 15521 for the singles). Did the model 18 500cc AJS and Matchless G80 of 1964/5 not use Norton oil pumps?I was sure the pumps were Norton units. It may be that they used the twin's pump and not the singles one.

Submitted by gordon_johnston on Wed, 07/11/2012

Permalink

I have an ES2 oil pump which is identical to the Domi pump except it has a hefty chamfer out of the bottom edge. I would post a pic but *****ed if I know where my camera is...

Submitted by ian_allen on Wed, 07/11/2012

Permalink

Hi.

The pumps are totally different! The feed and scavenge gears are on opposite sides for the twins compared to the singles.

The oil output is near the drive spindle on the singles, near the brass end plate on the twins. I'm pretty certain that a twin pump will not fit a single and visa-versa due to the position of the drive spindle.

Regards

Ian.

Submitted by grant_tiller on Thu, 08/11/2012

Permalink

Gents this is excellent information - thanks for your help.

In a way, I am disappointed as the later oil pumps are very easy to source compared to the ones that fit our much coveted singles.

However, this has stopped me (and hopefully others) from learning this the hard way!!!

Cheers!

Submitted by grant_tiller on Mon, 12/11/2012

Permalink

We stripped the oil pump at the weekend - they are a really simple lump of kit, and not remotely overwhelming!

It was really badly scored internally, perhaps explaining away some of the inefficiency (that and the huge amount of red silicon sealant used by the previous owner, which was clearly blocking the oilways all around the bike)

We have found only one proper gasket on this bike... the rest being substituted with the dreaded gunk, and way too much of it - but I digress.

Both top and bottom plate were badly worn - clearly there has been some grit or metal whirring around in there at some point, so we cleaned them upon some glass paper, then lapped on a piece of glass with some grinding paste.

Did the same with each of the internal gear wheelsin turn, cleaned thoroughly, assembled the gears into the pump body, and lapped the face as a complete unit (so that the gears and the pump body were uniformly honed across the mating surface of the top and bottom plates.

Cleaned with hot soapy water (to ensure there was no grinding paste left, agitated in white spirit (to get rid of the water) then reassembled with a liberal squirt of oil on all surfaces)

The whole thing went back together beautifully, and a twist of the shaft gives a nice silky feel, and that satisfying glugging sound when you can tell a pump is pumping!

Acouple of new bits to finish: new woodruff key (to replace the badly chewed one), top hat section union, and this time I went for the later conical rubber grommet instead of the fibre washer that was originally on there to take car of mating the pump to the case.

An easy exercise, which I would urge anyone to attempt themselves!

Submitted by ian_allen on Tue, 13/11/2012

Permalink

Hi Grant.

WHOA - I would NOT use the rubber grommet - the Dommi timing case is machined with a conical 'hole'specially to match this grommet - the ES2 is not and is totally different in this area. Using a 'Dommi's grommet' will probably result in it splitting and losing oil pressure.I would always fit fibre wide fibre washers -see Dominic Grove's photo 15522. From the Norton Manual - Place panel (Timing Case) in position and the washer should prevent the edges of the panel meeting the (crank)case by 1/32", This ensures that when the panel is tightened the washer is compressed making an oil-tight joint.

I've had my ES2for over 30 years and have never had any trouble using the fibre washers.

Regards.

Ian.

Attachments 1ES2-3.jpg

Submitted by grant_tiller on Wed, 14/11/2012

Permalink

Thanks Ian,

Mike Pemberton uses an o-ring in his excellent strip/rebuild DVD and on the grounds that the Commando item seemed to seat nicely on both pump side and cover, I figured it would be a good idea.

However, I'll take your advice and stick with the fibre washer!

Thanks for the heads up,

Grant

Attachments image.jpg

Submitted by colin_sharpe on Wed, 14/11/2012

Permalink

Very good advice Ian. I used to own an ES2 and I used a conical rubber. The result was a crack in the timing cover. Those castings made from melted down spitfires were a little brittle!

Colin.

Previously wrote:

Hi Grant.

WHOA - I would NOT use the rubber grommet - the Dommi timing case is machined with a conical 'hole'specially to match this grommet - the ES2 is not and is totally different in this area. Using a 'Dommi's grommet' will probably result in it splitting and losing oil pressure.I would always fit fibre wide fibre washers -see Dominic Grove's photo 15522. From the Norton Manual - Place panel (Timing Case) in position and the washer should prevent the edges of the panel meeting the (crank)case by 1/32", This ensures that when the panel is tightened the washer is compressed making an oil-tight joint.

I've had my ES2for over 30 years and have never had any trouble using the fibre washers.

Regards.

Ian.

Submitted by albert_sheean on Thu, 15/11/2012

Permalink

The oil pump on the singles has a body made of zinc, while the twin pump is iron. The oil feed gear is narrower than on the twins by about a 1/16th of an inch. The gasket is a red fiber washer and not the o-ring looking one used on the twins. It is possible to convert a twins pump to work on the singles, I know this because I did it myself by following the instructions given in an article in an INOA club bulletin. The article is somewhere in my archives (Pile of old magazines!) Essentially, the pump is turned over and the gears are altered a bit with a lathe. It works beautifully and finding a used twins pump is a damn site easier than unearthing a singles pump!

Submitted by simon_amos on Fri, 16/11/2012

Permalink

I just had the timing cover off my 38 ES2 and put a thin gasket in between as oil was weeping out the bottom. I'm a bit worried now after reading this that doing that may have taken the pressure off the fibre washer. There is still the same amount of oil returning to tank but I can't get my finger in far enough to block return pipe momentarily to check pressure. After a quick run today there was oil seeping out the bottom forward screw so I pulled it out to put some gasket goo on it and about 1/3 - 1/2 a tea cup off oil drained out. This was after it had been sitting for about 4 hours. Is this normal ? How would one tell if the seal was no good between case and fibre washer ?

 


Norton Owners Club Website by 2Toucans