Carb float bowl not sealing..? Warped?

[Zack19919853]

So got a carb gasket kits for my 1990 88 spl and on the bottom carb the plastic float bowl will not seal.. I have tried flipping the gasket. I have righted loosed screws to see if they would help no luck. Maybe the plastic bowl is warped? I have the aluminum ones off other carburetors from another 88 spl. And it seals! Will those float bowls work? They look a little more shallower than the plastic ones..

basically what I’m asking can I use the aluminum float bowls instead of the plastic ones?

 

[Chris1956]

It is easy to see of the bowls are warped. Put a steel ruler on the edge of the bowl. It will be obvious.

 

[iggyw1]

I believe the plastic bowl screw holes are numbered (at least mine were on my motor) and you need to tighten the screws in the proper sequence and not jut start at one screw and go around in a clockwise or counterclockwise direction. Also, if you have a way to see if the float is operating fully closed & fully opened with the aluminum shallower bowl on your carb , there should be no reason why you couldn't use it.

 

[jakedaawg]

You will want to verify the orifice sizes. The jets in the plastic bowl will not transfer to the aluminum bowl, different threads. Find the plastic bowl orifices, remove all 4. Look them up in the chart in the manual to get the proper ones in the correct thread pitch. Most dealers will have them in stocks, they may also cross reference them for you.

 

[Zack19919853]

Iggy they aren’t numbered I wish would make it easier.. this is off a 1990 Evinrude 88 spl. The carb says it is an 1989 and the other carbs with the aluminum float bowl says 1994. I looked up a new float bowl for a 1990 Evinrude 88 spl and it’s the same exact bowl as the 1994 float bowl. I am going to check out the orifices as jakedaawg suggested and make sure they are the same. I’ll give y’all an update as to how everything is going! I appreciate all of y’alls knowledge!

 

[Zack19919853]

Ok the orifices are the same size (26c) in the aluminum bowl as the “old” plastic ones. So I should be ok correct? So with the aluminum bowl being shallower then the “Old” plastic ones I could trade out the floats that came from the aluminum Bowl and put them on the carburetors I’m currently using? Almost just seems easier to use the other carburetors.. lol I am trying to keep the same parts on the same motor. If you get my drift!

 

[gm280]

Post a few pictures of both the plastic bowl and the aluminum one. Maybe there is a way to flatten the plastic one to fit again. If it isn't too far warped, it could be sanded flat again depending on how it is made. JMHO

 

[oldboat1]

^^agree. Use a piece of glass/window pane to identify warping, then use the same flat surface and some sandpaper to correct (figure eight strokes).

 

[havoc_squad]

Ok the orifices are the same size (26c) in the aluminum bowl as the “old” plastic ones. So I should be ok correct?

No, they are not the same orifices for the intermediate orifices. The metering hole size should be the same but the inner diameter thread size and pitch is different.

The main jet is the same, you swap that from the plastic to the aluminum carb bowl. If you bought a new aluminum carb bowl OEM from BRP/Evinrude, you'd get the conversion instructions included.

The factory OEM manual should have a orifice chart page listing the part numbers for a range of them.

So with the aluminum bowl being shallower then the “Old” plastic ones I could trade out the floats that came from the aluminum Bowl and put them on the carburetors I’m currently using?

If the float works correctly and does not show signs of needing replaced, I fail to see the need to start swapping out the float. This is not called out in the Evinrude/Johnson aluminum bowl replacement instructions to replace the float.

 

[Zack19919853]

Thank y’all for the information! What grit sandpaper should I use? Right now I used some RTV.. we shall see how it does... I have the carb off the motor and connected the primer bulb directly on carb no leaks and is still holding with a hard bulb for little other 24 hours..

 

[racerone]

???----Never use RTV in / on a carburetor or fuel system !!-------The bulb holding pressure has nothing to do with a warped carburetor body.-------The carburetor bowl has a vent to put atmospheric pressure on top of the fuel.----That is how carburetors " work " in fact.

 

[oldboat1]

^++. 200-400 grit wet/dry paper. Wet both sides so it sticks to the glass.

 

[racerone]

Ok----Perhaps I misread again.----Using RTV to glue the sandpaper to the glass.------Not sure how you can guarantee flatness when using RTV here.

 

[oldboat1]

(Think you read it right, or I misunderstood too. Think he's experimenting with an RTV "gasket" instead of trying to resurface.)

 

[gm280]

Years ago, 1972 matter of fact, Dodge Challengers had a Carter Thermo-Quad carbs on their high performance 340 engines. I know, I bought one new. And they used a "plastic" fuel bowl. And soon after that, the problems began. Heat warped those plastic fuel bowl carbs and it wasn't pretty. I swapped to a Holley four barrel and motored on... And lots of other engine manufactures started using plastic fuel bowls. And we all know why. Pinch those pennies and let the buyer beware.

Some plastic fuel bowls can be recovered with a flat surface and some wet/dry 400/600 grit sand paper. That is if there isn't some part sticking up in the plastic casting. If it is flat, sure it will work. But flatten it and don't go crazy or you will introduce other problems. Once it is flat that a feeler gauge can't slide under any area, it is flat. Reassemble and happy boating again... JMHO

 

[Zack19919853]

Thank y’all for the ideas! Yes, racerone you read correct the first time! Instead of fixing the plastic float bowls.. I have complete carburetors from a 1994 88 spl. On the 94 carburetors they are cast aluminum. Could I use those carburetors on my 1990 88 spl? Instead Of swapping float bowl on the carburetors..

 

[racerone]

Sure use the 94 carburetors with metal bowls.----Using RTV in a carburetor is a mistake !!

 

[Zack19919853]

Thank you racerone lol I know I was at my whips end with the float bowls.. I’ll try the sanding technique in hopes it works!

 

[oldboat1]

Don't use RTV sealant on your outboard. Get some BRP/OMC sealer in a can, or Permatex for use with fuels.

 

[Zack19919853]

Sure use the 94 carburetors with metal bowls.----Using RTV in a carburetor is a mistake !!

So like the 60 horse power there carburetored engine the float bowls are to stay on the same carburetor as the are all different. Is the 88 SLO’s the same? Are the two float bowls different from each other?