OK, so I got a kit and blocked off my oil injection on my Sport 400.

I did so in order to feel secure and go to smokeless oil.

So I started out my premixing on Amsoil Saber at 64:1.
I felt safe there as a starting point before going to a leaner ratio.
I think some guys run it at 100:1 even.


Anyways, before the blockoff, a trail plug was reading reddish brown on the blue injection oil.

I haven't gotten to mess with it much since the blockoff, but now the plug is black and wet.


The oil is injected after the carb, so I expected that if anything the thing would lean out on the air/gas ratio... making it run slightly leaner. In theory, at 64:1 there is about 1.5% less gas in the combustion charge.

My theory is that there's just too much oil with the Amsoil at 64:1 in my engine. More than is needed.

However, people on another site insisted that I was jetted rich... which to me makes no sense at all because it seemed fine on injection, and in theory it contradicts everything I've heard and read regarding the premix ratio and jetting connection.

Now I'm not really getting any feedback over there and I was hoping at least someone here would discuss it with me. I don't want to hurt my engine, but at the same time I don't want to make changes to find out they were not in the right direction.

Any feedback is appreciated.

 

I went out and ran it for a brief period... long enough to get a good plug read on the needle.

The plug actually looks pretty good on the needle.

It's wet and black on the pilot... which I refuse to touch until it becomes unavoidable.
(the thing cranks superb)


I'm betting that the oil injection was variable and pumping less oil at idle.
I bet the mix ratio is just a bit rich for idle, being that it's Amsoil.

Anybody have an opinion?

 

<div class="FTQUOTE"><begin quote>Originally posted by: duster

I went out and ran it for a brief period... long enough to get a good plug read on the needle.



The plug actually looks pretty good on the needle.



It's wet and black on the pilot... which I refuse to touch until it becomes unavoidable.

(the thing cranks superb)





I'm betting that the oil injection was variable and pumping less oil at idle.

I bet the mix ratio is just a bit rich for idle, being that it's Amsoil.



Anybody have an opinion?</end quote></div>

[img]i/expressions/face-icon-small-happy.gif[/img]YES the oil pump is a variable pump and quite adequate as is for all engine modifications and updates unless pump corroded or frozen, quite reliable in spite of reports otherwise. Good luck

 

<div class="FTQUOTE"><begin quote>Originally posted by: old polaris tech
[img][/img]YES the oil pump is a variable pump and quite adequate as is for all engine modifications and updates unless pump corroded or frozen, quite reliable in spite of reports otherwise. Good luck</end quote></div>


I had no doubt the system was very reliable.
I now have even less after having removed it.
Muniki.

But I do know of cases of failure... and sometimes I have the sort of luck that I would end up being one of the really rare few....

Plus I've been wanting to get more towards the smokeless end of the exhaust spectrum. The two together made me really nervous.



But if you want the truth... had I known what the blockoff kit consisted of for the price... and had I known it was going to be such a bear to remove everything... and had I known I'd be this nervous picking a mix ratio...

Well there's no question I would have just left the injection on and mail ordered some Opti-2 injection oil or some Amsoil injection oil (not sold locally).

 

Well, I moved on up to 72:1 [img]i/expressions/face-icon-small-shocked.gif[/img]


On the pilot the plug is better, it's a dark damp burgundy.
On the needle it's still a rust brown/red.
On the main it's almost cardboard brown, just a tad reddish.

The smoke and stink have improved.

 

It's still kicking at 72:1.

I'm considering a small trial of 80:1.

It's kind of like pour and pray though.........

 

Well, to update... I did go up to 80:1 on the mix.

Not much changed except the quad felt a little tamer.

I moved on up to 96:1 and have been running that for a while.

The quad feels the same as it did on 80:1... but the step to 96:1 is the step that yielded the most smoke reduction.


I'm sure gas octane has got to play some role here in how well it runs and how little it smokes. But it's been cold lately and I haven't been able to get a swift comparison.

In any event, I do miss the simplicity of the injection. No premixing and stuff with every addition of fuel. But I like the piece of mind.

The biggest hangup so far has been that I am now on my 3rd attempt on getting a good seal on the blockoff plate. The kit doesn't come with a gasket, so you have to make your own... and so far all of mine have leaked. The counterbalance oil weeps out of it.... BUT I THINK I HAVE FOUND THE CULPRIT.... (a threaded hole that exits behind)

 

Also, somehow someway I got a bonus significant gain in engine breaking action immediately after the conversion.

Can anyone explain how this is possible?