Re: Another Big Twin Observation….

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vintin


Replies: 580
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#81119

In three years I didn’t have a problem with too much oil in the fuel. In theory the original mix ratio could contain a little less oil. I did sometimes mix at 28/1 or 32/1 trying to compensate some of the added condensate oil added. The viscosity of the collected condensate looks to be the same as the original fuel mix. My system has a filter in the tank pickup and one in the fuel pump. Yes some unburned hydrocarbons from the input charge passing through the motor pushing out the burnt charge do end up overboard just like they do if no condensate is being collected. We see litter along our highways but there are stiff penalties if you are caught adding to it. There is a surprising amount of condensate collected. On my 1974 40hp ‘Jungle motor’ the condensate and vapor are directed back into the intake cover of the other cylinder eliminating the dumping of it overboard. It is run through a screen in the condensate reed valve system. This likely results in the poorer idle these motors are know for as the cool slow running motor gets it’s intake charge further enriched with oil and the heavier fuel tailings. Enriched right at the time enrichment is not needed which as least when running it back to the tank most of the enriched collected is burnt at higher RPM’s.

As a side note my 1974 Jungle motor routes each cylinder’s condensate and vapor to the other cylinder intake cover as I mentioned earlier. These condensate reed valves allow for each cylinders’ condensate to be collected separately, which I have done. The lower cylinder collect more condensate when it was routed to two seperate collection tanks.

Here is a photo and link to a Suzuki vapor separator and recovery assembly that contains a float and valve system that routes vapor into the incoming air stream and uses a fuel pump to pump the fuel/oil condensate back into the fuel system before the carburetor. This is self contained under the cowling and is similar to system OMC also used. https://www.ebay.com/itm/1987-2003-Suzu … 0005.m1851

1974 40hp Jungle motor:

Photo showing seperate routing of the condensate from the collection reed plate cover: