'64 BSA Lightning Rocket - Carburetor Rebuild

I was pleasantly surprised that the Lightning Rocket still sported its original Monoblocs and they were in decent shape. The slide stop screws had been tightened a bit to much which put a crimp in the slides causing them to bind. Once the slides were out examination of the bodies showed they were in serviceable condition although new slides are required. Some of the fittings were rusted or had pliers put on them at some point in their life which grooved them up. One of the jet holder covers was seriously grooved. Why??!!!???!!

A bit crusty but mostly there....the original 389 Monoblocs

The slides were slightly galled and binding.

Plier marks are normal violations on these old carbs but why the grooves????

I have had good results with my ultrasonic cleaner. This takes the bits back to their core metal in most cases. I use Simple Green in the washer to assist in cleaning and have found high heat to aid in the process. I have soda blasted carbs in the past with good results but prefer the ultrasonic cleaner now that I have the process sorted.

My secret weapon...the Harbor Freight Ultrasonic

One supplement to my process this go around was to use CLR, which is a calcium and lime removing chemical, on parts with corrosion not removed by the ultrasonic. It is aggressive and should only be applied for a couple of minutes. This final step made my carb bodies look great. I finished them with a paste wax to keep the corrosion from coming back. This is my first attempt at this process and I will have to see how it plays out over time. The initial results are very good.

Parts cleaned up....ultrasonic...CLR.....wax...good to go....

Ready for assembly.....

The bores showed minimal wear so I decided to place new slides in them which worked well on my RE build. One of the foremost experts in the field says the bodies will last for 3 sets of slides if treated properly. While I have had carb bodies bored in the past I prefer not to have the expense if necessary and I do miss the choke which you sacrifice upon a re-bore. I have heard great things about the new Amal Premiers and will try them when replacements are necessary.

The bores required a slight cleanup to get the new slides to fit. High spots were sanded with 220 grit and a brake hone was used to get a tight slip fit. The mounting flange was also dressed flat with a file to correct a past mechanics over zealous wrenching. 

I chose to use the anodized slides for this rebuild. 

They are a pit pricy but I think the additional cost will be worth it. 

Ready to go, just need to set the float height.....shim if necessary. 

Time to sort out fuel taps, lines and air cleaners.......