Hi. I'm Dave.
I can try to assist you with this, but there are a LOT of possibilities here, and I need to ask a bunch of questions to get a better idea of what is going on.
When you say "Just won't turn over" do you mean the starter will not crank the engine(No-Crank)? Or are you saying that the starter cranks the engine, but the engine does not start and run. (Crank/No-start)?
If the "service engine" light is on, this is normal if the engine is not running. However, have you checked the computer system for possible fault codes?
When the engine overheated, was it turned off by the driver? Or did the engine stop running before the ignition got turned off?
When you changed the oil did it smell burnt? Was there any sign of engine coolant mixing with the oil?
Starter cranks/no start. Computer system not checked, can not get into a dealer shop until next Monday. Engine overheated and was turned of by ignition key. Oil was not burnt. No sign of coolant in oil. Engine was started after had cooled off and ran.
Is it possible that you may have left something unplugged? like did you have to disconnect any electrical connectors - maybe to move things out of the way, when you did the other work?
Also, is this vehicle equipped with any aftermarket equipment such as alarm system or anti-theft system? Or is it all factory original?
The answer is no to all of the above. No electric connections removed and no alarm system. In 2004 there was a factory recall for the fuel pressure regulator recall. That was replaced. The fuses for the fuel injection system are good. Is it possible that even though the fuel pump is pumping fuel that there is not enough pressure to make it up to the carburetor. Where is the line to ck. that. Can you tell me.
Suzuki does not supply any "fitting" for checking fuel pressure (like many manufacturers do). You must disconnect the fuel line and install an adapter to connect a fuel gauge.
You really should get a code reader and see if there are any fault codes before anything else is done. You may be just wasting your time if there are fault codes set or the onboard security system has locked due to the battery being removed.
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