V4 Looper Mystery hose..........

[sutor623]

Hey guys was checking all my hoses and realilzed I have one that is just kinda hanging around.

All of my primer hoses are in their proper places.

All of my fuel and recirc hoses are hooked up.

The hose that goes from the intake manifold to the airbox is hooked up.

But there is a long small hose that runs from the block (in the cylinder 4 area, just under the bottom carb). Is this a vent hose? Or do I need to figure out what/where this thing came from???

 

[Chris1956]

Some airboxes have two vacuum hoses, one on top and one on the bottom.

 

[sutor623]

Some airboxes have two vacuum hoses, one on top and one on the bottom.

Ok, I will have to look into that. I don't think my airbox has two but I will put up some pics tonight.

Anyways, thanks for your feedback in my thread about double oil and fouled plugs. You were spot on about carb issues, because I surely found some. I was hesitant to agree because I had been through them 2 times at that point!!!

I found that all of my plastic carbs had warped bowls and mounting surfaces, so hopefully flattening those out will remedy my situation. Kinda makes me feel like a dummy. I have worked on so many types of outboards, but never one with plastic carbs. Guess what I will do from now on? Check ALL carbs for warpage whenever doing a tear down....................

 

[sutor623]

So I figured out it is in fact a vent hose, that doesn't go anywhere. It comes off of part #12 on this diagram, and the name of the part is "vent fitting." #317121

 

[Chris1956]

OK, if you are sure it goes nowhere. On my '98 150HPV6, there is a nipple on the bottom of the airbox that holds a vacuum hose. The top of the airbox has a slip fit opening for a second vacuum hose. I would have thought the V4 would be the same.

 

[sutor623]

OK, if you are sure it goes nowhere. On my '98 150HPV6, there is a nipple on the bottom of the airbox that holds a vacuum hose. The top of the airbox has a slip fit opening for a second vacuum hose. I would have thought the V4 would be the same.

Hmmmm, there is a hole up there but doesn't look like it will actually hold the hose. I guess I could slip it in there and see if it stays. Thanks

 

[Chris1956]

I looked at the service manual(whoopee). On my '98 60* V6, the air box is part of the fuel recirculation system. The output of the vapor pump feeds the top airbox opening (slip fit, likely burns any vapors pumped from the fuel bracket). The bottom of the air box is plumed to one of the manifolds, likely sucking up any liquid fuel spilled from the carbs..

 

[sutor623]

Ok thanks I'll have to look at that.

 

[Faztbullet]

It does not go to air box, it ties to the upper reciric line that goes from bottom to top bearing. This is to vent the bottom bearing and keep fuel from puddling and fouling bottom cylinder. All 90 degree loopers have the extra fitting right when they when to the closed desk block. This is a mod you can do to older motors and help idling.

 

[sutor623]

It does not go to air box, it ties to the upper reciric line that goes from bottom to top bearing. This is to vent the bottom bearing and keep fuel from puddling and fouling bottom cylinder. All 90 degree loopers have the extra fitting right when they when to the closed desk block. This is a mod you can do to older motors and help idling.

Thanks fazt. So I already have a line that runs up from the bottom cylinder, to a check valve, then up to the top cylinder. Where would I tie this line in? Do I need to add a T?

All of these lines are already in place:

 

[Faztbullet]

It just follows the return line from bottom to top and is wired tied to that line at the top..

 

[sutor623]

It just follows the return line from bottom to top and is wired tied to that line at the top..

Cool, thanks Fazt, easy enough!