tohatsu outboard 90hp

[simon23]

My outboard is a 90 hp tohatsu autolube.it keeps oiling the plugs up after about minutes even at wot.was thinking about disconnecting the autolube and premixing .is it just a case of blanking the autolube tank and leaving some oil in so the float doesn't hit the sensor at the bottom ?? Thanks for any help .

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[colcreate]

Originally Posted by simon23

My outboard is a 90 hp tohatsu autolube.it keeps oiling the plugs up after about minutes even at wot.was thinking about disconnecting the autolube and premixing .is it just a case of blanking the autolube tank and leaving some oil in so the float doesn't hit the sensor at the bottom ?? Thanks for any help .

Sent from my GT-S5830 using Rib.net

Not that familiar with Tohatsus but generally with autolube (which has a mechanical driven pump) I would try and figure out what the problem was before premixing.
You could be running lean with gummed up carbs which would increase the oil to petrol ratio and cause excessive oiling. Switching to premix if that's the case will not solve the real problem of gummed up main jets. If its been a while since the carbs were stripped and cleaned I would do that first as well as a compression check.
Also check the spark plugs are correct and/or replace maybe try non resistor plugs (may be ignition problem and weak spark).

[simon23]

Thanks for your reply,the engine was serviced at the begining of the summer,included was a carb strip,clean and rebuild.also compression test which was fine.it has done about 20 hrs since.less than 10 hours ago it was fitted with 2new coils and 3 plugs(i don't no what they are called but they are the plugs with no electode so no gap).all work was done by a engineer and I'm trying to contact him,but was hoping for a quick fix before the end of the season and he is 100 miles away from the boat.

[peterwhite]

I'd check the oil you are using is of decent quality and definitely tcw-3 oil. Also check the plugs I'd need to look but I'd put money on them being the wrong plugs for that engine. Usually only Mercs and the odd Evinrude use that sort. I'd think you should be on b8hs or bp7hs or something in that region. I think the tohastus run a similar ignition system to yams. I'd certainly check you're on the right plugs though.

[spartacus]

Sparks for that engine are NGK B8HS-10 or BR8HS-10. Oil wise, any TCW III compliant oil will do. I use Quicksilver and works for me (M60C engine).

[simon23]

The oil is quicisilver,the one for engines with carbs.i have a set of the origonal plugs will give them a go.engine ran great the first day i ran it on the other plugs!

[spartacus]

Originally Posted by simon23

The oil is quicisilver,the one for engines with carbs.i have a set of the origonal plugs will give them a go.engine ran great the first day i ran it on the other plugs!

If you have the original plugs, give them a quick clean with a soft bristle copper wire brush if they have any carbon deposits. Don't know what the gap is, but rarely need adjusted.

[simon23]

Originally Posted by spartacus

Sparks for that engine are NGK B8HS-10 or BR8HS-10. Oil wise, any TCW III compliant oil will do. I use Quicksilver and works for me (M60C engine).

Can't remember which they were but the are what they say to use on the sticker on the engine

[colcreate]

Originally Posted by simon23

Thanks for your reply,the engine was serviced at the begining of the summer,included was a carb strip,clean and rebuild.also compression test which was fine.it has done about 20 hrs since.less than 10 hours ago it was fitted with 2new coils and 3 plugs(i don't no what they are called but they are the plugs with no electode so no gap).all work was done by a engineer and I'm trying to contact him,but was hoping for a quick fix before the end of the season and he is 100 miles away from the boat.

Sounds like you have had a few problems and all within 20hrs of it being serviced. 2 coils at the same time? Gapless plugs (aren't they for high speed running/racing) a hotter plug burns off the oil deposits better than a lower heat range plug. Cheap quick test put a set of the recommended plugs in and try them. How bad is this oiling up? Measure the oil and fuel levels accurately before your next run and check the usage afterwards by topping up from a measure jug then calculate the ratio.

[simon23]

Runing at wot it lasted about 5 minutes before engine died to a chug.cleaned plugs and same again.the only real days boating ive had it was runining at about 60:1