T140 bottom end re-build

[gumpt1oo]

I am afraid I am going to have to strip the old T140 down!
I have been hearing an intermitent rumbling noise at tick over, and a heavier knock under acceleration. I suspected the drive side main bearing so I whipped the primary cover off and I can lift the crank about 0.5mm!
So next weekend I will start to strip her down, I will post pics of all the horrors I find!

[gumpt1oo]

Busy day today.
First job was to make some room in the garage for the strip down as there was quite a bit of junk about.


I had a couple of old doors and some bits of timber laying around so I make up a bench to lay the parts out on as the strip down progresses.


And let battle commence!


Tank seat, carbs and pipes off.




Parts bagged and labelled so I remember where they go back!


head off, love the silicone around the gasket!


All looks pretty good.


Next the clutch and alternator to remove.


Clutch removed and locked with locking tool ready to undo cam, crank, and rotor nuts.


Timing cover off,


Before I removed the nuts from the cams I checked them for end float. Bit of an agricultural method but it works. Push a wooden wedge behind the timing gear so that the cam is pulled out as far as possible, put a steel ruler across the case and measure the gap with feeler guages. Remove the wedge and push the cam as far back as it will go and repeat the measurement. The difference between the two measurements is the cam end float. Both of mine were 15 Thou, the spec is 13 to 20 thou so there both ok.




And that is where I got to today, I am now stuck until I get a 15/16th socket for the inlet cam nut, and an 1 1/8" socket for the exhaust cam, and crank nuts.

To be continued..............

[ventura]

Looks like you're going to be kept busy for a little while Steve!!
Keep you out of mischief!!

I like the temporary workbench.
Oh, and the carpeted garage floor!!

I see you haven't brought the bike bits into the house yet.
Unlike some!! ;D

Keep up the good work, and hope it all goes smoothly with nothing too dramatic found.


V.

[Lake]

"....stuck until I get a 15/16th socket for the inlet cam nut, and an 1 1/8" socket"

You're not stuck, I know someone with a massive toolkit. I've got them and you're welcome to use them anytime!

[gumpt1oo]

Thanks Kieron, I will give you a ring tomorrow about the sockets.
I have made a bit more progress today after I went for a morning ride.
Progress today,

[Lake]

No bother Steve. One thing that's always struck me about older bikes is the lack of fold-up footpegs, and why people don't make a hidden type mod for them. Having seen you ride it could be worth doing.

[gumpt1oo]

I had a quick blast up to Lake's house last night for a rummage through his tools . And I now have the correct sockets. Thanks Kieron. So tonight I bolted a bar to my clutch locking tool and manage to get all the nuts undone and removed the primary side complete, and the gearbox outer cover. She is nearly ready to come out of the frame.

[gumpt1oo]

bit more progress made tonight. My parcel of goodies arrived which included a puller to remove the crank pinion and a base nut spanner.


So the barrels are of and the engine is out!




Pistons look fairly new to me, on the crown they are stamped ID6 .040.
I assume the .040 is 40 thou oversized, anyone know what ID6 means?

[Lake]

Yes, the .040 indicates they are oversize. I had .020 oversize piston in the old bike after it was rebored.

[gumpt1oo]

And the crank cases are finally apart!



Time to start cleaning everything and replacing bearings!

[ventura]

Nice job Steve!! And great pics too!

Looks like its coming on nicely, and not too many stumbling blocks so far.

Lets hope it stays that way.
Lookin' forward to it being back together again and we have our first 'old bike' run of the year!




V.

[gumpt1oo]

Jun 3, 2012 13:50:24 GMT -5 ventura said:

Looks like its coming on nicely, and not too many stumbling blocks so far.
Lets hope it stays that way.
V.

You spoke too soon!
First problem is that the drive side main bearing has spun on the crankshaft and has worn the crank!
After much researching and phoning around, the only repair I could find was to have the crank ground and sleeved to fit the bearing. I was not keen on that idea, so I have bought another crank that is in excellent condition!
I have also found that the little ends of the conrods are worn and need reaming and bushing, so I have bought a new pair of conrods.
So I fitted the new rods to the crank with new shells, all ready to fit in the cases, when I noticed a mark on one of the conrods. One closer inspection, there is a flaw in the casting next to the little end oil hole!
So I am now waiting for a replacement conrod!

[gumpt1oo]

Well the new conrod should be here by the weekend, but I did make a bit of progress today.
Just got this lot back from the powder coater, nice and black and shiny!

[teebee]

Dang Steve, this is very impressive. Particularilythe speed at which you do the job. It also seems you are well connected with those you need to outsource stuff to (like powdercoating). Now I know who I will ask to do a full strip-down and rebuild of my bike

[gumpt1oo]

Thanks TB, my wife keeps telling me, 'you don't have to get it finished this week, it's not a race!'
But when I have a project going it sort of takes over!
I made a bit of progress this weekend, got the frame and forks assembled, but I am still waiting for the conrod to arrive to start the engine re-build.