Offroad-Express

Here's something to watch for if buying a Zuk, it's very well documented online. I believe after 1995 they fixed this issue, but I'm not entirely certain.

Basically from factory, the 17mm bolt that holds on the crank pulley (lower timing gear) was only torqued to almost half of what it should be.
If this was never remedied (Suzuki did release a notice a couple of years later, what happens is that the key used to align the pulley on the crankshaft ends up gouging the keyway out.
If it does, and it's loose - you will experience weird power issues as the pulley moves on the crankshaft and throws the timing in and out.
If it's stuck tight (like mine), it will mean the pulley is anticlockwise from where it should be - meaning you can't use the crank markings to time the engine. It will slowly throw out the timing as it destroys the key and keyway.

Worst case scenario is that the key gives way and the pulley turns freely, in a 16v engine this will mean massive damage to valves and pistons.

What to look for - pull out the spark plug in cylinder 1, turn crank pulley clockwise until the marking on the large accessory pulley lines up with the 0 marking on the timing belt cover (you can't see the problem pulley and cam snub without removing the timing belt cover).
Put something down into the cylinder via the removed plug (a screwdriver, straw - make sure it doesn't fall in and is sitting on the piston.)
Now moving the crank back and forward, you will see when the piston reaches the very top of it's travel - this is true Top Dead Centre (TDC).
Check the crank markings, they should be aligned perfectly - mine was quite a way out as you can see in this picture -

http://www.suzuki-forums.com/attachment ... g_2623.jpg
Note the piston is at TDC, but the key on the pulley is anticlockwise about two teeth from pointing directly up
As I said this can be checked without removing the timing belt cover or the accessory pulley which bolts onto the crank pulley in the picture.

A more simple approach would be to take a torque wrench with you and check that the crank bolt is at 96 foot-pounds if it's not, there may be hidden damage or trouble waiting to happen.

It took a lot of work to get that pulley off using a tool we made, but here is what I found -

http://www.suzuki-forums.com/attachment ... g_2635.jpg

http://www.suzuki-forums.com/attachment ... g_2640.jpg

You can easily see that the key has been quite damaged, and the keyway has been gouged out toward the left of where it should be due to the force being on the key.
With the crank bolt at 96 ft-lb of torque (what it should be), the bolt is holding the pulley to the crank - there shouldn't be any force on that key but from factory it was the wrong torque.

There is plenty of documentation online about this problem, and there is a fix if your keyway isn't too damaged using a cold weld product which I will have to do.

I've spent a lot of time in the last two weeks researching this, and I thought I'd post it here so anyone buying a Zuk is aware of this problem and how to quite easily check for it.

dt

Bugger That is very concerning. That really sucks man, those little 1.6s are supposed to be a bullet proof engine!

Seeing as you've already gone this far, why not just drop the crank and take the crank and pulley to an engineering shop to have a new keyway machined on the opposite side ?

Why have you got the head off ?

Hey Kernels, yep it is a bit of a worry, a quick google search will bring up dozens of forum pages about this issue.

I don't really want to pull the crank, it's already been about 3 weeks without my daily driver And there isn't an issue there.

The fix used online works fine - as with a new bolt torqued correctly - that pulley aint going to slip.
That key is just there to align the pulley and shouldn't be taking any weight.

So a new key, JB Welded straight into that mangled keyway will hold it forever as long as that bolt is torqued correctly. - it's getting Loctite on the threads too.

Head is off because I had an overheat, and decided to overhaul the top end before I rely on it to get me into the places I'm going - at 248000KMs it's not a bad idea really, only a few hundred bucks of work.
I'm taking the head in to be tested today, just to tick that off the list.

If anyone needs more info check out suzuki-forums.com, theres a lot of info on this particular problem there.

dt

dtchch wrote:That key is just there to align the pulley and shouldn't be taking any weight.

Aahh, I see. Yeah, sounds like you're onto it then. Too bad about the touble you've had, definitely not the norm for these little machines. On the upside, you will probably find that it goes great when you're done

Cheers
HeinB

FnH fella!

It was running well until my overheat (actually ran fine after that too), I may have gone overboard in someone elses eyes but to me it is important that it's running perfect - I can't afford it to blow up when I'm out hunting somewhere.

A few hundred bucks and a couple of weeks work is well worth what I paid for it to get it chugging along nicely.
I'm looking forward to putting it back together again, and having some garage space

Sounds like you've spent a bit of time sorting it. We swapped the crank in one of those engine on a piece of firewood with a chainblock hanging from a tree branch to lift the motor out. Hardest thing was getting that bolt on the front pulley off
You definitely would have been able to do the swap given how much work your putting into the engine already.

It's hard finding the time, I dont want to try track down a crank, pay too much for it plus replace seals and bearings etc. Whole new can of worms!
It's too time consuming to get that done while working 8-5, nobody is bloody open in weekends!

Great engines to work on eh? My mate lifted his G13B out by himself