[Sfbrain]

Thanks Tony and Jay for the very quick replys      



PM"s sent



Thanks again



Steve

[Sfbrain]

 





Not one but two brush holders  





Then the condensors (more of these later  





The carefully prize the circlip off the top of the points posts









Then remove the points and their timing plates, and your left with this









I always keep everything i take off carefully recorded









Clean everything up and start to rebuild



First the right hand timing plate









Then the left hand one, which fits over the top of the right









Then replace the brush holder (thanks again guys  





Now we look like this









Then fit new points









Next new condensors, However these days you dont get a replacement like the old one, you actually get two seperate ones









And when you try to fit them, you find the wire lead on the right hand condensor, is not quite long enough !!!

 





So its out with the soldering iron  





Then fitted them, reconected all the wires and the jobs a goodun  





Still waiting for the oil pump shaft bush, but should be here tomorrow.



Next the oil pump refurb (so out with the big plastic bag         )



Steve

[Bridlad]

2? which did you use ?

[Sfbrain]

 

2? which did you use ?

Hi Tony  



To be honest, i used them both  



Jays mounts were a bit "sloppy" and your brushes were a bit too worn  



So i re soldered Jays brushes into your mount  



Best of both worlds  



Steve

[Bridlad]

result!

i never have sloppy mounts  

[Brass]

Good to watch  

[Sfbrain]

Ok, as promised, the Oil Pump, this can be a lttle tricky but with care (and a couple of tricks) its not difficult  





Immidiatly there was a problem  





Then undo the nut on the top of the pump and remove the washer/plate and shims









Use a sheet of clean paper to keep the removed parts on, in the order you remove them  





Next rotate the top piece (where the cable fits in) until the pin is free.

In this case there was a roll pin fitted, originally there was a small threaded pin fitted, either is ok









Remove the pin and pull the piece up gently and remove with the spring underneath









Your collection of bits should now look like this









I next remove the knackered union, just to make handling easier









Now you need some "special tools"  





Loosen the 4 screws on the top of the pump, then put in the plastic bag









IN THE BAG, remove the 4 screws and GENTLY take the top off the pump.



The top piece will look like this









Take the central rod, its spring and washer out of the top, and put with your bits









Now take your elastic band and tie 2 knots in it









Now returning to the body of the pump, STILL IN THE PLASTIC BAG, gently pull the middle out BY THE CENTRAL SHAFT !!!



DO NOT PULL IT OUT BY THE COG WHEEL !!!









Not all pumps are the same inside, but all are very similar. In the pic below you will see two VERY small pins, inside the cog wheel, these are held in place by the cog wheel and the central shaft, they have a SPRING under them !!!









If you pull the copg wheel up by more than 2mm, the pins will fly out (ask Mancini  





Your bits should now look like this









There is a wavey washer underneath the cog wheel, and also this one in the bottom









There are 3 seals to replace









Change the seals, clean up all the bits and gasket surfaces and you can start the rebuild  





Until its safely back together









Next rebuild the pump top and fit a new gasket









Carefully push the thin shaft (in the cap) into the new seal in the centre of the main body









carefully push the two halves together, DO NOT TRAP THE NEW GASKET



and replace the 4 screws









Ok, now refit the tang of the big spring into the top of the body









Fit the other end of the spring into the hole in the top "cam" piece, and compress straight down, pushing the cam piece over the top of the pump









Rotate the cam piece anti clockwise until the small hole appears in the shaft and replace the pin









rebuild the top with its shims and washer and top nut



Then the jobs a goodun  





All i need now is a new one of these









NSRNICK is looking for one for me, but in case he hasnt got one, please have a look in your sheds      



Next i will fit yesterdays electics plate back on the engine, and if my new pump shaft bush arrives, fit the pump too.  



Steve

[Sfbrain]

Ok, the last couple of posts have been refurb jobs so time for a bit of rebuilding  





After cleaning up the rotor face with some white spirit, fit the woodruff key into the crank end and push on the rotor









Next the points cam









Then tighten up with the cam bolt









Next on with the points plate, first feed the cables through the hole in the case









Then gently ease the points on the plate over the cam bolt and secure to the cases









Conect the neutral switch wire and locate its rubber seal in the case









Dont forget to push the cable rubber through the case, like most the rubber is cracked but i will repair it with some super glue later









Next finish the clutch mechanism, locate and fit the ball bearing









Followed by the push rod









Next locate the front sprocket fixings









First the bearing bush









Not sure what Ed wants to do about the gearing, so i have just located the bits









Next locate the clutch operation mechanism









Then fit to the engine outer case









Now the electric side is sorted, so the cases can go on  





Next some "Dremil Action" on these  





Steve

[Sfbrain]

OK, more on the rebuild  





Do the dremil work on the edges BEFORE removing the masking tape from the painting, then you wont get little filings in the ports and cylinders  





Next get together the pistons, new rings and new circlips









There are 3 rings per piston (with a dykes top ring)









First the expansion ring goes in the bottom ring groove.

Followed by the oil ring









Then fit the top (Dykes) ring, making sure the gaps in the rings line up with the location pips in the grooves









What i do next is check everything is going to fit correctly on the bench, by fitting the pistons into the barrels.



IF YOU DO THIS, ONLY INSERT THEM IN THEIR CORRECT POSITION !!!, if you fit them rotated from their correct position you may find an end of a ring will expand into a transfer port  





Fit a circlip into the INSIDE side of the piston









Then lubricate new little ends with a little oil and locate in the con rod









You can now put the piston over the end of the con rod and push the gudgeon pin through to the pre fitted circlip, and fit outside circlip.



NOTE the crank well filled with a rag, you dont want to drop a circlip down there now  





Repeat the above process for the other piston  





Now, reaching under the barrel, pinch the rings into their grooves and slowly lower the barrel over the top of the piston









Carefully locate the barrl over its 4 studs and ease the piston into the cylinder









Then repeat for the other barrel









Fit a new head gasket









Then on with its head  





Then repeat for the other side









OK, just a few bits left now to finish her off  



More later

Steve

[[Arrow]]

Nice work, unusual finish on those pistons. Looks like they have been shot blasted all over    Never seen that before.  

[Sfbrain]

 

Nice work, unusual finish on those pistons. Looks like they have been shot blasted all over    Never seen that before.  

       Very nearly, they have been vapour blasted. Ed"s rebuild is a "budget" rebuild, whereby whatever needed to be replaced was, but anything that could be reused, was  



The bores were sound and the original +0.25 Yamaha pistons fitted well within tolerances, so savings were made as a rebore and new pistons were not needed  



So new (Genuine Yamaha) rings, little ends and circlips were fitted the piston and gudgeon pins were cleaned up and reused  



Steve

[Sfbrain]

Hi All



Here is probably the final installement of Ed"s 350 engine rebuild  





It fits here









Next collect the pump drive bits









Push the shaft through from the outside and secure with its e clip, over a new oil seal









Then mount the drive gear









Next, turn the casing over and fit a new seal for the kick start shaft









Then fit a new gasket over the clutch and locate over the two dowel pins in the engine cases









Now lower the outer case over the kick start shaft and rest it on top of the two dowel pins, DO NOT PUSH IT HOME OVER THE PINS  





Fit the oil pipe rubber into the case









Then (while the case is still resting on top of the dowels) fit all the case screws, ensuring they go through their holes in the gasket.









Now you can push the case home and tighten the screws  





So i fitted the union and then fitted the pump to the shaft in the case









And thats about it  























Steve

[Sfbrain]

With Ed"s engine all but done, i looked back over to my bench and saw this ...........









                 



This ones a 5 speed 250A (with 350 barrels and heads), this one is for Rattle (also of this parish   )



However, its part of a complete bike restoration that i will show here (but will skip the engine rebuild, as your probably all done with engines now       )



Steve

[Colin987]

I know this thread is very "picture heavy" but it was designed to encourage people to have a go themselves  



I hope it proves useful  





Thanks.  Extremely interesting - will certainly be using it to guide me through my rebuild.



Colin

[Welsh_Dragon]

Excellent Steve, sure lots of people will find this usefull