secrets of the timing chain

[acton mike]

the timing chain in the 318 of my '84 D100 had enough slack in it so that one could make two chains out of it

I lined up the timing marks as shown in my Haynes manual before i pulled off the old chain/sprockets set

Now I am having trouble getting the keyways lined up and the sprockets on the crank and cam shafts

they are out of line just a smidge

but, as you can appreciate, there is very little tolerance

I can only work at it for short periods of time as it is bloody cold in my unheated garage

I know many of you have done timing chains but I have never done a timing chain before - timing belts many times but a chain - never- well, the timing chain on my CB350 'cycle doesn't really count because in that case there is some slack that is taken up by the tensioner

SO - what is the secret - I cussed at it a few times but that only sems to make the darn thing more obstinate

[bherder]

If your old chain was streched far enough, the timing marks/keyways won't 'line up' no matter how much you fiddle-fart around with the old set...
(If everything lined up just right, you wouldn't need to be replacing it all, right? ;) )

The few times I've done/replaced the 'set' is this...

Get things as CLOSE as you can with the old set. It will be 'off ' (Especially if you jumped a tooth) so just do the best you can. Better to have the crank timing mark 'on' than the 'cam' mark on...

Before you put the chain on, put the sprokets on and line up the timing marks ... Worry more about the crank mark being where it's suppose to be, rather than the cam... The cam is much eaiser to turn/tweek ....

(You should only need to turn it a little bit. DO NOT try to crank anything around 360 degrees with the other end stationary! At worse, you should only be off by 10-15 degrees or so even if you jumped a tooth..)...

Put the bolts back in (Hopefully all you'll need is the cam sproket) gently turn the cam sproket, and get the timing marks lined up juuuust right. Once you have things lined up, take any bolts out, TRYING not to turn anything. (Usually you can 'eyeball' it, but it helps to have a straight-edge you can line up and hold up on the center-lines of the cam/crank bolt holes and check your timing marks with that)

Get your new chain and sprokets and hang the chain over the cam sprocket and let the crank sprocket dangle WITH the timing marks lined up... Hold the sprockets up to the edges of the crank/cam shafts and start to gently tap them onto the shafts. Do a couple of alternating taps on each sprocket, to keep things square and going on evenly. If you have everything lined up good before hand, they should slip on without too much effort.
It will be a tight/close fit, but if you get everything lined up right, and tap the sprockets on gently and evenly, it should go pretty smoothly.

Assemble the rest of engine :D

[acton mike]

I took the old cam sprocket and using a couple of small buts and bolts and a piece of flat scrap metal I made a tool for turning the camshaft; I used the old sprocket(and its timing mark) and I plan to plan to line up the timing marks with the new crankshaft sprocket in place

The theory is that if I line up the timing mark with the old camshaft sprocket and the new crankshaft sprocket, then when I put the new cam sprocket on it should line up perfectly ( again that is the theory)

Once I getthe timing marks set I will follow your advice for getting the chain on

The marks were pretty well lined up before i took the old sprockets off and I made certain not to move the crankshaft

Then I guess it is jest a case of

[acton mike]

it is on

fiddly work that was Timing marks line up too



Thank you for the advice

It sure would be a nicer job in the summer

I think I would prefer sweat in my eyes than frozen nose drippings on my upper lip

Anyway, the chain is on

I will put the rest of it together in the couple of days I have off after Christmas

If I am not on this site again before Christmas, then Y'all have a merry Christmas; I gather if I was in Texas and wishing more than one person a merry Christmas, I should say all y'all have a merry Christmas

[bherder]

it is on

:party0003

fiddly work that was Timing marks line up too


Great stuff!!!



Thank you for the advice

It sure would be a nicer job in the summer

I think I would prefer sweat in my eyes than frozen nose drippings on my upper lip

Hahahahaha!!!!! I know what you mean! I've got a pretty full mustache/beard and sometimes I come in out of the shop and my wife says 'What's that shit all over your face?' .... (It's the SNOT running out of my nose that has froze to my face and never knew it was there, because I never felt it... :D )

Anyway, the chain is on

See? Santa Claus gave you a present!

I will put the rest of it together in the couple of days I have off after Christmas

If I am not on this site again before Christmas, then Y'all have a merry Christmas; I gather if I was in Texas and wishing more than one person a merry Christmas, I should say all y'all have a merry Christmas

You to bud!

[Speed Dragon]

I alway just get it close w/ the old set, pull it off and put the new set on and line it up w/ that. It's not a big deal if it's off a bit w/ the old one cause it's coming off anyway, just make sure the new set is right.