Air cleaner â63 Atlas

Previously ernie_olivo wrote:

I recently purchased an air box for my Atlas (389 monoblocs). Iâve attached pictures, and have a few questions:

- is it correct?

- is it missing anything?

- is the fine mesh inside all of the necessary filtration?

Then on to the fitting...lol

Thank you,

cheers

Ernie

You have the dual monoblocs correct? Yours is a chopped monobloc filter with a single dimple.

There also was a similar 1966 389/689 unit that had 2 dimples for the fuel inlet, the third style was for concentrics with no dimples.

I have one of each for my dual carb 63 Atlas, 66 Atlas with 389/689 and my 68 atlas with concentrics.

The mounting plate to the carbs, held by the screws, and sealing rubber grommets are missing.

That air cleaner is for the 1966 version of the Atlas twin, and it was fitted to the G15CS, and N15CS models with the left and right handed Amal Monoblocs. It would have also been fitted to the 1966 version of the Atlas and 650ss models. The mounting plate for this air cleaner was made specifically for this air cleaner and it will not fit any other version. That air filter was made for one year only. The chopped Monoblocs had a different air cleaner mountings as the later air cleaner 033030 that was used for the later Amal Concentric carbs will also fit the chopped Monoblocs. The mounting plate is 23552, the air filter is 23555. As per page 35-36 of the Master Parts List 1966-1967-1968. It is not for a 1963 Atlas as that air filter is clearly for a twin and the early Atlas models had a single Amal carb.

That air cleaner is only different from the other wedge shapedair cleaners by the way it was mounted. The internalof it has a mess filter that is normal oiled and then put back inside. This as per a Norton Atlas service release pamphlet in about 1964. There is also another bent plate inside the air cleaner, drilled with holes and painted black that keeps this oiled mesh in place inside the filter.The two triangular side of the air filter are attachedto the air filter with two through studs, nuts and lock washers. The inside of the triangular cover for these air filters had a cloth mating that was shaped to the inside of the triangular covers. These air cleaners could be ordered from the factorywith chrome side covers for these wedge shaped air cleaners. These side covers are now being made in stainless steel.

There are four versions of this wedge shaped air cleaner. One small one and one longer one. Two for the Amal Concentrics and two for the Monoblocs, and I also suspect there may be a fifth one for the earlier 376 Monoblocs on theearlier 650 twins.

There are four versions of this wedge shaped air cleaner. One small one and one longer one. Two for the Amal Concentrics and two for the Monoblocs, and I also suspect there may be a fifth one for the earlier 376 Monoblocs on theearlier 650 twins.

There are four versions of this wedge shaped air cleaner. One small one and one longer one. Two for the Amal Concentrics and two for the Monoblocs, and I also suspect there may be a fifth one for the earlier 376 Monoblocs on theearlier 650 twins.

Previously anthony_curzon wrote:

There are four versions of this wedge shaped air cleaner. One small one and one longer one. Two for the Amal Concentrics and two for the Monoblocs, and I also suspect there may be a fifth one for the earlier 376 Monoblocs on theearlier 650 twins.

OK Anthony I heard you the first time...!!!......The difference being the sizes and threads of the adapters that screw on to the carb input which with the rubber grommet form part of the airtight seal for the bracket to compress against the main part of the filter. Cheers to all, Howard

That is not my fault but the web site. The air cleaners have different size brackets that attach the air filter to the screw on sleeves to the carbs. The monobloc and concentric ones are different in the thread size and how they are made. The air cleaners have the welded on mountings in different places. The bolts are the same for all the air cleaners, as there is also a washer that goes with them.

For the missing parts, try Walridge Motors who are in Canada who should be able to supply the parts required if you give them a part number. This company also has a really good catalogue that you can access via their web site www.walridge.com