Is my separator plumbed properly????

[Kzaker]

2000 Merc 200 EFI OT153924

having issue at idle and checking a few things but when I looked over the fuel lines, it appears that my gas line runs into the pump, out to the filter but I think it may be going into the outlet and not the inlet. Can someone verify which is the inlet and which is the outlet by looking at this picture?

[JOE54]

brass 90 should be inlet from pulse pump

[Kzaker]

Thank you. It's backwards then. Guess I'll find out what difference it makes when I flip it around! I wonder how many years it's been like this...

[JOE54]

I stand corrected one I just looked at is backwards looked in manual and yours is RIGHT 90 is outlet to vap separator

[Kzaker]

I looked at this exploded view and it also looks like mine is backwards: this diagram shows inlet depositing gas into center of filter, outlet to VST.? Would it make a difference?

[123trentm]

Elbow is inlet, straight fitting is outlet

[123trentm]

I would not run it at all after swapping lines until you replace filter

[Kzaker]

I have a new filter already. I'll switch, flush the best I can and install new filter. But I'd much rather see, or have someone look at their efi 2.5/3.0 and verify BEFORE I switch it.

[123trentm]

I can't look at one right now, but a filter is fed in the center, You can see the raised area where the elbow attaches goes to the center where it threads on

[Kzaker]

For the sake of ruining a new filter, I'll wait to have someone confirm this plumbing. I too agree that it should be fed through the center of the filter but as I have little past experience with these, I'll hope that someone with more experience can verify the orientation..

[123trentm]

I just looked a 2.5 200 efi. Pulse goes to straight fitting.elbow goes to canister. The diagram shows it the other way around. I looked up your serial and it is exactly like the pic younposted

[123trentm]

Now I'm curious, which is right?

[Kzaker]

Hahaha.. yeah.. I'm a bit curious also... also curious if it would make any difference: still same area of filter media, same lift height, filter can't collapse if flow is from outside to inside but- I'm not expert. All I know is my motor idles like sheet:)

[JOE54]

guys I just looked at 3 diff mtrs all the same hose from pulse to straight fitting,guess this means outside of element is what catches debri wouldnt you think that would be the case optis with spin on filter is fed on side also

[leonreno]

The intake (from tank) is the outside fitting and the exit (to motor) is the middle fitting, or in this case the one with the elbow fitting. The gas enters on the outside and is spun around the filter as it goes the the center, the debris are caught by the filter and the water falls to the bottom as it makes its way to the center of the filter.

Look at pictures online of other filter housings and the arrows will sho you the outside fitting is input to filter and inside fitting is the output fitting. Don't know why Mercury doesn't have arrows on the housing.

Also, think of it this way, feeding the gas from outside gives you a lot more surface area on the filter as opposed to feeding the filter from the inside. Only makes sense to feed gas in from outside fitting.

[123trentm]

It makes sense what you are saying. What doesn't make sense is the mercury diagram he posted earlier in this post shows the opposite. I looked it up with his serial# and get the same picture.

[leonreno]

Diagrams are made by people and people make mistakes, it seems most if not all of the motors checked have exit through the middle. the motor riggers know what is correct and not the one person who created the diagram. Also, look at the small fitting from the middle fitting under the cover. Should be a small "pipe" coming down from middle fitting to insure the motor is getting fuel and not any air. The outside fitting will not have a fitting under it as it is just dumping fuel in and not pulling it out.

[Kzaker]

I had to read that a few time to understand what you were saying! Lol. Thanks; and yes, the screw-on portion that the filter goes onto is below the "input" (makes sense).

(Either direction has the same sq.in. Of media, just will pass the air until completely full of fuel).

back to figuring out poor/smoky idle::::::::