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2iar
25-08-2005, 11:50 AM
Hi All,

I'm after a bit of advice on fuel mix ratio.

I've got a 9.9 1990 Yammie. It has a plate that says the mix should be 100:1. However, I've read in the past that I should really use 50:1, so that's what I've been doing.

The motor's ok when cold, but sometimes needs 2 or 3 pulls to start when it's hot. It also cuts out at slow/idling, but only after warming up.

Could it be the fuel mix, or anything else? It had a good ($470) service about March that replaced heaps of gaskets, impellor etc, and hasn't been used all that much since.

Fishin' Dan advised me about vapour lock, so I've been making sure thre pressure valve on the tank is open, but that didn't seem to cause the problem as it still persists.

Any ideas Ausfishers?

Mike

Fishin_Dan
25-08-2005, 01:08 PM
And sometimes it doesn't start when you are floating away from the ramp ey Mike!!! ;)

2iar
25-08-2005, 01:19 PM
Well I didn't want to mention it Dan, but a non-big-girls-blouse such as myself started it on the 2nd pull :D

To be fair, pulling that winter whiting on plastic must have tired your arms out :-)

Mike

Fishin_Dan
25-08-2005, 03:31 PM
Ha ha ha! You'll keep Mike ;) he he he he... ;D

Have you checked for water in the motor at all? This sounds a bit like what was happening to my old motor (RIP). IT had water in the carbies... Do you have a fuel filter/water seperator in the fuel line? That would be the first thing I would do... At the same time, add a little bit of Metho into the fuel as well. If this then runs better, then that would point to that being the issue.

2iar
25-08-2005, 03:54 PM
Have you checked for water in the motor at all? This sounds a bit like what was happening to my old motor (RIP). IT had water in the carbies... Do you have a fuel filter/water seperator in the fuel line? That would be the first thing I would do... At the same time, add a little bit of Metho into the fuel as well. If this then runs better, then that would point to that being the issue.

Go easy on me big fella, I'm a bit new to all this...

1. How do I check for water in the motor/carbies?

2. I don't have a fuel filter/water seperator. Do I just buy one, whack it on the fuel line between tank and motor?

3. if so, which side of the primer bulb?

4. What's a decent make and what would they cost?

5. How come it's ok when it's cold if there's water in the fuel/motor? Surely it would happen all the time?

6. Is my original query about the ratio a possibility?

7. have you heard of vitabrits? :D :D :D

Thanks for any help,
Mike

Fishin_Dan
26-08-2005, 10:44 AM
;D LMAO! I'm new at this too mate, just going on what's happened to me, and what I've heard/read. There are many other people on here much smarter than me at this! I'll see if I can answer your questions a little....

1. Ummm.... Simple answer - Dunno - Mine got picked up when I put it in for service...

2. You can buy them from Whitworths. They're not much, and pretty easy to fit. Bring the boat around, and I'll help you if you like. There's a whitworths right near me...

3. Between tank & primer bulb would be better...

4. Dunno the make, but not alot

5. Was just a guess/question... Could be because the fuel would float on the water, but as the motor runs it pulls some of the water through??? As I said - guessing...

6. Probably...

7. ;D Yes mate.... But am on Special K at the moment so I"m not such a fat b@$%rd!!! ;D ;D ;D HA HA HA HA!!!

gogecko
26-08-2005, 11:31 AM
As DR Karl says "do the experiment". Run 100:1 fuel for a few trips and see if it makes any difference. If it does, youll know what to use. If it doesnt, then you know its a service issue.

Make sure you empty the old fuel out first. Dont mix them.