Hi all, i have purchased a 1994 Fountain Lightening with stock Twin 525SC (454cid). I cant find what oil is recommended for this motor but previous owner used straight SAE 40. I was thinking of converting to 25w40 or maybe an Amsoil. Anyone have a suggestion for oil types? Motor has 725 hours and not raced just used for cruising. Also i occasionally get flame outs approaching dock at low rpm. I have changed all cap and rotors and wires and had both carbs professionally rebuilt. Still have flameouts and was told by someone to change electronic chip from a v8 to v6. Has anyone heard of this?

Please describe what you mean by flame outs.

I started doing 10 setups every time someone started an oil thread

NIce abs speedy ! lololol

525sc’s have performance (crane) flat tappet cams. An old fashion zinc loaded oil is recommended. 40w is fine. So is 20w-50.
My go to is still Vavoline Racing VR-1.
Here is a really good deal on it:

1-900-Call-Hunter

OP the selection of oil to run IMO would be the water and ambient temps that you run in, Im not a fan of straight weight oils, Im in the midwest and have always ran VR1 20-50 in all my marine engines

then don't visit a 2 stroke jet ski forum. every summer we get 200,000 new 'what kind of oil' threads.

the v6 module was a common swap back in the day . it gives them more advance at idle. that helps them from dyeing when docking. they were notorious for fouling plugs and were hell on coils. but you couldnt break them !

Motor shuts down,