[prosmart]

Greetings

I have recently returned to the fold and bought a 96 SJ80 that has had a G16B fitted

It has a few issues that came out a day or so ago including a tendency to overheat, a shriek from the belt and a lack of power.

Water is moving, water pump is quiet. Belt tension seems okay. Battery is showing 12.8 volts BUT once the motor is running voltage goes from 12.8 up to 18+ volts!! It has a 100w MXA325 alternator fitted.

Can anyone recommend a Suzuki shop that can diagnose and fix these issues on the south side of Brisbane? I found Suzi Auto in Springwood but wondered if anyone would recommend them (or anyone else).

I can't do this myself as I am working 7 days a week 12 hours a day at the moment.

Thanks for your input

Nigel

[Gwagensteve]

Are you asking for assistance from the board on diagnosis or just a recommendation for a shop?

Unfortunately cooling a G16B in a sierra isn't well understood and the consequences of overheating are often a cracked head and/or failed head gasket and therefore ongoing overheating issues, lack of power etc.

Does the engine run a factory Vitara viscous fan?
are the heater lines hooked up as they would be in a Sierra - i.e through the heater tap?

[prosmart]

Gwagensteve wrote:

Are you asking for assistance from the board on diagnosis or just a recommendation for a shop?

Unfortunately cooling a G16B in a sierra isn't well understood and the consequences of overheating are often a cracked head and/or failed head gasket and therefore ongoing overheating issues, lack of power etc.

Does the engine run a factory Vitara viscous fan?
are the heater lines hooked up as they would be in a Sierra - i.e through the heater tap?

Thanks for the response.

TBH a diagnosis won't be much use to me as I work long hours and am really time poor.

I am far more interested in a recommendation for a shop - just concerned that I find a decent place as this is quite new territory for me.

N/

[Gwagensteve]

I guess what I'm trying to say is you have found a shop, that's the easy bit. You still need to understand the problem to direct them because taking a car in and saying "stop it overheating" is likely to be a very fraught, long, expensive and frustrating process.

Help me understand more about the problem. You have a conversion. If the shop you take it to isn't super familiar with the conversion or has a particular way they do the conversion and it doesn't match the way your car has been done, that will be "the problem"

Read between the lines - I'm also telling you that G16B cooling is poorly understood, that's by everyone, even shops that have been doing these conversions for years.

Does it have a thermo fan or an engine driven fan
Does it have a fan shroud
Is it a vitara G16B? (thermostat at the front of the engine, crossover pipe for the air intake)
is the heater hooked up?

Not necessarily related but does it have a functional check engine light?

I'm trying to assist you what to tell the workshop what to do, otherwise they're most likely to tell you everything that's "wrong" about the conversion you have because it's not like they do it.

My first step would be get the coolant system pressure tested. if it's not leaking but not holding pressure you have a cracked head/ failed head gasket. That's not the problem, that's a symptom of a problem with the engine conversion.

The SOHC 16V G series cylinder head requires constant coolant flow out the back of the block/head. All factory SOHC 16V installations have some constant coolant flow out the back of the block. In the vitara and Jimny the heater core has constant flow. In all the FWD applications, the thermostat is at the back of the block so there is full coolant flow across the engine. In 99% of installations of Vitara G16B's into Sierras, the vitara heater hoses are hooked to the heater tap and core on the sierra and it's called good.

This causes the cylinder head to be dead-headed at the back of the engine and steam pockets form which cracks the head and or pushes the head gasket out. It is imperative that a G16B in a Sierra has the heater hoses hooked up for constant flow, either by bypassing the heater and tap or out by bypassing the tap out (heater on constantly)

Any remedial work on the fan or radiator or shroud, water pump thermostat etc that doesn't address this issue will result in the problem coming back in the future.

That's why I think you need to take the ar to the shop with a solid diagnosis behind you and don't trust the shop to "fix" it as I'd be quite confident they don't know this.

I worked this out by A) noticing how many G16B's overheat in sierras and then crack heads etc despite running for 25 years in a vitara without an issue. B) comparing coolant flow diagrams in the FSM for the G13 Sierra and G16B vitara.

[prosmart]

Apologies for the silence. Had to wait to get the car from my son in laws place to mine this morning. We bought this a few months ago for our runabout trailered behind the Unimog we are planning to retire into. My son in law has been using it as a daily driver since then. The story is that the conversion was done at the same time as the rest of the work (lift kit, winch, diff locks, rock sliders) for a Cape trip that never transpired. He sold it to the guy before me who has literally used it as a commuter and occasionally a night under canvas. So much so the location of the connection (somewhere in the cab) for the winch remote and could not tell me why the UHF was non-functional ("I never used it to be honest").

• It appears to have a clutch fan plus a thermo fan. Haven't got it up to operating temperature yet and I can't find an override switch for the thermo fan so I can't test it yet.
  
• There is a distinct whistle when the engine is revved from cold - almost a belt squealing. This slowly (almost) disappears as you drive.
  
• Fan shroud is fitted.
  
• Thermostat housing is at the side of the engine. I presume this means it is not a Vitara. Does that suggest that it s out of a Swift? Any way of checking from the engine number? G16B338168
  
• Heater is functional
  
• Engine light works.
  
• Belts look and feel good

Now the interesting part(s).

Just took it out and ran it around for 30 minutes or so in third at around 4000 rpm - could not get the engine temperature above the middle of the gauge no matter what I did. I did notice though that the temperature gauge fell from 1/2 to 1/4 every time I stopped at the lights- maybe a dodgy thermostat?

When I got back I grabbed a meter to measure the output of the alternator (measure at 18+ yesterday). Didn't even get that far. As soon as I lifted the bonnet I saw that the "Condition Indicator" plug on the battery had blow right out and fumes were pouring through the resulting hole along with battery acid spraying all over the shop. I'm going to take a wild guess and say "Voltage reg has died".

I might start by replacing the alternator and then see what transpires from there.

Thanks so much for the input to date - very much appreciated.

[Gwagensteve]

Sorry for the delay in replying.

If the thermostat is on the side of the engine towards the front it has a Vitara manifold on it, not Swift/Baleno.

A thermo fan shouldn't (ever) be required if the cooling system is in good condition, the vitara viscous clutch fan is fitted and functional and the shroud is in place.

The gauge shouldn't read as high as 1/2 in normal operation. They normally sit at about 1/3 (i.e below 1/2)

Faulty thermostats are rare, it sounds more like the thermostat has been removed which would be a misguided response to overheating (same as fitting the thermo fan)

My guess is still that the head gasket has failed due to the reason mentioned earlier and there have been a couple of attempts to "fix" the associated overheating.