remove timing chain without removing gears?

[amamet]

is there a way to remove the timing chain on a 78 g5 without removing the gears?  i am replacing the chain with one that has a master link along with the bow type tensioner.  just wondering if i can do it with removing everything since i can just put the chain on and connect it in place.  i dont have the 4 prong socket nor a replacement hex nut if i drift pin the ring nut off.  i assume a dremel will make too much of a mess regarding metal shavings, but how about a bolt cutter?  not using the chain again anyway.  just an idea, probably a bad one tho, i think
thx
allen

[Kiwi_Roy]

Yes I'm sure a bolt cutter will make short work of it.
The Dremel might be ok if you stick some Al foil around behind the chain to catch bits.
If the chain has less than 50,000 in it you could just add the new tensioner.
If your crankshaft nut is a hex type a regular 32mm  3/4" drive socket will slip over the shaft and can be turned with a pipe wrench.

[amamet]

already purchased the master link style when i bought the tensioner, i know i could have reused it as the bike has under 20k miles according to the odometer, but who know if its accurate or not

[Kiwi_Roy]

I'm not sure why but I found the bolts that held the old tensioner were too long to go without so I hack sawed the bracket off and put the bolted part back.




I think the top RH bolt also holds the bearing in place
I scratched a note onto the sawn off bracket to let the next owner know when it was changed out.
A quick check of the timing is to watch the valves rock at TDC (both valves will be partially open), one link out it will be way off.

[Chuck in Indiana]

I know Patrick says you can, but I couldn't on the one I tried. The bolts were too long and the head hit the gears while still engaged. I would avoid grinding, period. I take pains not to have an engine open when *any* grinder is in use, much less on the engine.

[mrrick]

It looks like you might have room to use a chain breaker tool on the old one, after removing the tensioner?
I've never actually seen one (chain breaker) deep enough to use on a duplex chain, but maybe they are out there?

[fotoguzzi]

I've done it, stuff the area with an oily rag to catch the dust and grind down two pins on a link of chain then knock out that link, chain comes off.
that was my first timing chain swap about 20 years ago, since I've decided it's not much of a big deal to pull off the sprockets just don't loose the woodruff key under the crank gear.

[Stevex]

As foto says, it can be done, I've done it too. You only have to grind one head off one pin. do it with a pin at the bottom of the engine and use lots of rags. The rags collect all the crap.
The oil pump sprocket is easily removed to access the new tensioner bracket and when refitted, it is the only one of the three you can rotate to help bring the chain round.
I found it easier to remove the tensioner blade and spring and then fit the mounting bracket and chain first, then fit the blade and spring last...gives you more room to work in.
Just remember to align the timing markings on the top two sprockets and make sure they don't move as you link up the new chain.
The pic shows mine fitted.

[80CX100]

When I did mine, I was worried about dealing with pulling the gears/setting the woodroffe key properly on the reinstall,, so I cut my old chain off. Cut the head off a pin down at the bottom,, had oily rags stuffed in the case behind/below with clean paper towel and light plastic as well. A dremel cut off would be the tool to use,,, I picked up a small diamond cut off wheel rig for my drill,,, it worked, but only lasted long enough for this one job.

ps, when it came time to install the new valtec chain tensioner, I had read about it being stubborn to go in,,, from discussions, concensus seemed to be,,"just man handle it in,, that it was a very tough piece and wouldn't break",,, I proved that theory wrong,,,lol. The 2nd new one installed with gentle mindful coaxing.

[Chuck in Indiana]

Absolutely no offense intended, but I'll say again..

I take pains not to have an engine open when *any* grinder is in use, much less on the engine.

I've seen what can happen to a precision machine when carborundum finds its way into it. When we were building precision stamping tools, grinders of all kinds were in a galaxy far far away.  You won't get all of it when you clean up. Will it kill your engine? Probably not. Will it do it any good? Definitely not.
Really.. it's not that big of a deal to do it right.