[Thruan]

Hi guys. I have a 1996 coily Sierra.

Currently running a G13ba. Its developed a bad big end knock . The engine only has 90k on it.

Looking at my options and some advice. Cheapest to most expensive.

Replace the big end bearings only (can this be done in car or will the engine/box need to come out?)
Full rebuild. Can do all the work myself, except the machining and such.
Straight swap with another G13ba. used or rebuilt (if I can find one local)
Full G16b conversion. again can do all the work myself, but finding an engine and loom could be hard.

Id love to go the full g16b route, but its by far the most expensive and time consuming.. Reading the conversion guides on here, they are all the leafy models. Is doing it to a coily any different?

What's the groups opinions oh the best route to take?

[Gwagensteve]

I disagree that the G16B swap is the most expensive. The most expensive option by far would be a rebuilding your G13BA.

(It's probably not a big end knock - it's most likely a piston has dropped a skirt and is slapping around. Pull the sump to confirm - odds are there's skirt in the sump. This is a known problem with the SJ80 G13BA)

Anyways,

I don't think you could accurately measure the crank journals without pulling the crank, so that's engine out. It genuinely doesn't take long to pull the motor, in fact, trying to do the job without pulling the motor will take far longer than pulling the motor and doing what ever needs doing.

The only differences between the leaf and coil cars, from the point of view of a G16 swap is that you already have the swirl pot in your fuel tank and the flange to accept a vitara/baleno swimmer pump, and the common G16 conversion extractors might foul the tie rod in an SJ80.

The best way to find a G16B is to buy a whole, rough or damaged Baleno. They're dirt cheap, unless you would also like an automatic and power steering, in which case find a rough/damaged vitara. Neither is terribly hard to find as it takes very little damage/roughness to make either car uneconomic to register, so they're being sold very cheaply. Obvious provisos that the vitara version is more prone to cracks and has both an AFM AND distributor.


I wouldn't bother rebuilding a G13 unless you have deep pockets and access to a very good machinist. The combination of open deck/alloy block/ovalised bores makes rebuilds very expensive or frustratingly short lived.

Personally, i don't see the sense in pouring money into a G13BA only to end up with the same marginal performance and carby nonsense.

[bumstein]

Gotta agree with Gwagon here.

Does it still run ok or does it fart around and drive badly? If it runs then keep using it until it shits itself entirely, at least that’s what I’d do but that option isn’t for everyone!

Keep looking around and see what you find, you might come across another G13BA in which case it’s an easy swap. Alternatively you might decide to hold out and look for a Baleno Motor. As Gwagon points out they are fairly plentiful, especially if you’ve got the time to spend searching for the right one. They pop up on Gumtree and Pickles salvage auctions. You’ll find something for sure

[Thruan]

Thanks guys.
Didn't realise that rebuilding them is such a pain, was going to get a kit from online and do all the work, just get the head skimmed or whatever..

Is the baleno motor as easy as the Vitara motor or is there extra steps/parts required?
I have a mega squirt 3 sitting here, so planning to use that to run the engine rather than splicing the looms together (yeah I know, probably a stupid idea but meh..)

[Thruan]

The car runs great other than the knocking, still hoots along happily at 100km+ feels a touch down on power, but I could be imagining it.

[greenzook89]

I suspect my Ba dropped a skirt, never confirmed it but it was a bit more rattly and slightly down on power. Still did 5000ls like that till I sold it.

[Gwagensteve]

Baleno is harder than vitara (sump and water piping mods) but is a better result. Looms don’t need to be “spliced”- if you think fitting a megasquirt will be easier than adding a VSS and CE light and IG+ feed to between looks, you’ll never complete a megasquirt install.

[ZUZUKI]

Played with a G13BA rebuild in a coily about 4 months ago.
It ran surprisingly well, made nasty noises & blew a bit of smoke - in fact that was the customers biggest complaint - he had to keep topping up the oil.
A section of piston broke off, but skirt stayed in place, just banged up & down the bore along with the piston. Had been doing so for months, you could see all the smooth edges to the break, but it had no oil control rings on that piston.
You can pull the sump with the engine in the car & see what you can see.
The big end bearings (conrod) can be done, but as Gwagen says, easier if the motor is out.
4Cyls are easy in this regard as there is a mid point where all pistons are either 1/2 way up or 1/2 way down.
Undo the caps, Push the pistons up the bore & change shells. If you want to do mains (crank) bearings = engine out.
So, strip short block, cleaning, new pistons, rings, bearings, machining, re-assembly to short block by a professional engine reconditioning business was about 3k.

G13BA is also used in EFI form in early Jimny - this could be the best conversion, especially if you thing your current 1.3 goes well enough, as in slightly newer motor, EFI, all bolts together - find the right car & get P/S as well!.
Rgs, Michael

[shep]

I would pull the rocker cover off the G13 and just check that it one of the rocker gear screws hasn’t fallen out.
Seen it a few times and it can sound like a big end knock.