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Question about the 2 check valves in the carb.

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thetered

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I rebuilt my carb with a OEM kit. (Didn't replace the needle or seat or mess with any of the adjustment screws)

Go to start it and it will not start at all. Reading more on carbs here I suddenly realize the two round discs are supposed to be installed the correct way (I never even looked at the back of the directions that talk about it that came with the kit.) I don't know if they were installed the right way or not. It'll be a few more days before I get a chance to tear it back down and check, but if they are upside down would they be damaged now even if I did turn them the right way?

I didn't replace the spring either as it seems like most people just kept the original one in.

Also, as I mentioned I did not replace the needle and seat because they were not with the kit. I pulled the needle and I thought it looked ok, I didn't pull the seat though. I didn't do any pop off test because I didn't have a tester (I knew it was rolling the dice.) But since I can't get it to fire I am gonna make sure to get one for testing when I rip it back apart in a day or two.
 
Yes the metering diaphram must be in the right way. (the round disk with the holes/red dot should face towards the carb and hit the metering arm. The metering arm should be flush with the bore of the carb. Also, make sure the fuel pump is assembled correctly, just look at the holes and picture it working, then determine where the gaskets go. It helps to look at the old gaskets sometimes and see the indentations and be able to see where they went on the carb before. Also, make sure you connected the lines up correctly (fuel in and return lines, make sure pulse line is installed and has no cracks in it, etc)
 
You're talking about the diapraghm. Yes the check valve need to be install with the ink mark away from the carb. The side to black grommet goes through is the side the ink mark should be facing.
 
Thanks, i still dont think mine is correct. I ordered two new ones with some other stuff other day because i rubbed the ink off trying to put them in during my carb rebuild other day so im just gonna redo it with the new ones before i put the carbs back on.
 
You don't need the ink mark really. Set it flat on the table and see which side it is arched and the high side is the ink side.
 
Just curious, Does it matter? I mean the plugs are holding the valves in pretty good and tight so what would be the difference if they were in the other way?

Would there be any noticeable symptoms ?
 
Because from the manufacturer they come off of a roll. If you put it in the opposite of the arch the outer edge won't touch and seal. Its hard to explain. Think of the disc as the shape of a bowl and you will understand.
 
I get what your saying, I'm just wondering how significant it will be and what the symptoms of something like this would be.
 
thetered said:
if they are upside down would they be damaged now even if I did turn them the right way?
Click to expand...

The two disks should be fine if they seal well all around their perimeter and aren't cracked or folded, the perimeter of the disk should be touching the pump body sealing surface all around 360 degrees, it should not be curled up. Be gentle with the grommets, not to tear them.

I think you're better off with the original metering springs.

I always change the needle/seats, definitely if the rubber needle tip is grooved or torn and the needle has a special lubricant coating on the rubber tip that can wear off.

But, metering needle issues will show up mostly in hard starting(needle doesn't open) or can flood with fuel at low speeds(needle sticks open) if the needle is worn.

I guess a needle/seat probably doesn't have to be replaced if it's only been used for two or three seasons, but then the carbs shouldn't need rebuilding so soon either, unless the fuel is dirty.
 
Put the SECOND set of brand new check valves in my carb today and it still won't pass that stupid test..... I made sure the ink is facing awat from the hole tat each goes into. I think thats correct. The instractions say the ink should face away from the carb and thats confusing. I still havent saw anybody clarify that. Sounds like the ink should face away from the metal on one side and toward the metal on the other to both face away from the carb. Unless it means away from the actual pump section that they are going into.

Fuel Pump Verification

Check fuel pump valves operation as follows:

Connect a clean plastic tubing to the fuel inlet nipple (see Picture A) and alternately apply pressure and vacuum with the mouth. The fuel inlet valve should release with pressure and hold under vacuum.
CAUTION: Some fuel may be present in fuel pump. Be careful not to swallow fuel when testing.
Repeat the same procedure at the fuel outlet nipple.
This time the outlet valve should hold with pressure and release under vacuum.
 
Pointhunter75 said:
Put the SECOND set of brand new check valves in my carb today and it still won't pass that stupid test..... I made sure the ink is facing awat from the hole tat each goes into. I think thats correct. The instractions say the ink should face away from the carb and thats confusing. I still havent saw anybody clarify that. Sounds like the ink should face away from the metal on one side and toward the metal on the other to both face away from the carb. Unless it means away from the actual pump section that they are going into.

Fuel Pump Verification

Check fuel pump valves operation as follows:

Connect a clean plastic tubing to the fuel inlet nipple (see Picture A) and alternately apply pressure and vacuum with the mouth. The fuel inlet valve should release with pressure and hold under vacuum.
CAUTION: Some fuel may be present in fuel pump. Be careful not to swallow fuel when testing.
Repeat the same procedure at the fuel outlet nipple.
This time the outlet valve should hold with pressure and release under vacuum.
Click to expand...

In this test, you're just blowing through the pump in the same path the fuel takes if the pump is assembled, there are two check valves and blowing into the fuel inlet you push air through both valves and out the outlet. The air should be blocked from flowing in reverse(out the fuel inlet).

Did you connect your tubing to the pulse fitting and push/pull the diaphragm to pull air into the inlet and push that same air out the outlet?

These instructions show how to install the valves, you may need a flat surface such as a window pane or mirror to see which way the valve disk is curved (there is usually a slight curvature which should face the fuel pump body:

http://www.winderosa.com/files/Download/instructioncheckvalveinstalation.pdf
 
I put each in with the ink facing away from te metal, is that right? Thats tge confusing part. Directions say face ink away from the CARB not the pump piece itself. So the ink should be facing te same direction according to that, in my head.... In other words should the ink face away from the actual pump plate that they go into or the carb itself when the pump plate is mounted to the carb??
 
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Pointhunter75 said:
I put each in with the ink facing away from te metal, is that right? Thats tge confusing part. Directions say face ink away from the CARB not the pump piece itself. So the ink should be facing te same direction according to that, in my head.... In other words should the ink face away from the actual pump plate that they go into or the carb itself when the pump plate is mounted to the carb??
Click to expand...

Sounds like the instructions are unclear("CARB" should be "pump plate"), probably b/c they were translated from Japanese. One of the blue lines will face the carb and the other won't. The valves are attached to the pump plate. Both of the blue lines should be facing away from the pump plate, you should insert the rubber grommet through the side of the disk that has the line on it.

But, more important than the line, is the reason for the line. The reason for the line is, the valve disk has a slight curve in it which could affect it's ability to seal against it's seat in the pump body. So check for this, it will help you understand why they put blue lines on the disks, and once you know why, then you won't need the blue lines anymore.

MY disks don't have blue lines on them, but some of them do have a slight curve in them.

If you look carefully at the one-way check valve pocket in the pump plate, you can see once it's assembled it's designed to only allow fuel to pass through it in one direction. The edge of the mylar valve disk should contact the pump plate seat over the entire perimeter of 360 degrees. If the valve is curled upward away from the pump plate where it's attached by the rubber grommet, the grommet may not hold it down tight against the circular sealing surface.

If you take the valve disk and place it on a very flat surface like a mirror, you might notice one side appears convex, while the other is concave(naturally!) This is because the mylar material was rolled up onto tubes during manufacturing (a necessary evil) and the film took on a permanent curve. The circular disks are cut from that previously rolled sheet, so they will have a slight curve in them as shown in the PDF file I attached. This is an undesirable fact that may require the disk be oriented to work properly and it's why one side is marked with a blue line. Thus, the concave side of the valve disk should face the pump valve plate sealing surface, the rubber grommet is installed from the convex side of the valve disk and into the hole. If there is dirt between the valve disk and pump body, then the valve will probably leak a bit because it cannot contact the pump body sealing surface over the full 360 degrees.

Whats important is, the valve disk only allows fuel to pass through it in one direction, you should be able to see how this might be by studying the configuration. Notice that the fuel should come through the several holes in a circular pattern under the valve disk, and push the disk away from it's seat as the fuel comes through. That fuel should not be able to flow back through in the reverse direction, the disk should lay flat against it's seat and the disk should not have any wrinkles, folds or cracks in it, otherwise fuel can pass by it in both directions.

I know we can get you going on this, I think you're getting close. Feel to post a close up pic if you can, showing your valve disk installed in the pump body.
 
Thanks that clarifies it for me. Lol finally! I laid both sets flat and still cant see any curvature. They're def facing the right way. We'll just see if they work on the ski eventually. I've been slacking on putting it back together lately...
 
Pointhunter75 said:
Thanks that clarifies it for me. Lol finally! I laid both sets flat and still cant see any curvature. They're def facing the right way. We'll just see if they work on the ski eventually. I've been slacking on putting it back together lately...
Click to expand...

Okay, that's cool! I think I'm going to go play with my seadoo for a few hours before sunset, I want to wash the bilge out with hot water and check the pump bearing oil for water. Tomorrow I'm going to try spending the day on the water.

Have a good one, guys! :)
 
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