Carburetor question on restoration I’m working on 1992 40 hp MSHQ Yamaha

[Douglasdzaster]

That is not what the parts catalog or the service manual shows. What be we missing?

In the picture the fuel filter is missing. Was that way when I got it. Since then I’ve ins the filter and it looks like your pic. Also the oiler had been disconnected and tank removed. You can see the VRO pump sitting under the fuel pump.

 

[Sea Rider]

I'm plainly in agreement that fuel pump it's not attached to the lower carb, pics in post 16 shows it all. Must have clicked by mistake the Tohatsu 40 HP spare parts page which lives side of the Yam's 40 page. Let the one who has never had a senior moment to cast the first brick.....

Happy Boating​

 

[99yam40]

In the picture the fuel filter is missing. Was that way when I got it. Since then I’ve ins the filter and it looks like your pic. Also the oiler had been disconnected and tank removed. You can see the VRO pump sitting under the fuel pump.

I sure hope the drive shaft for that pump was removed also.
with no oil running thru the pump and it is being driven still could be bad

 

[Faztbullet]

View attachment 339808

 

[Douglasdzaster]

View attachment 339808

Will no let me open attachment.

 

[Douglasdzaster]

I sure hope the drive shaft for that pump was removed also.
with no oil running thru the pump and it is being driven still could be bad

This was done by a previous owner I have known idea about the shaft.

 

[99yam40]

time to find out

 

[Douglasdzaster]

time to find out

Do they make a plate to cover where the oiler is or do I just make sure they removed the drive and put it back?

 

[Faztbullet]

yes there is a aftermarket block off kit...

 

[Douglasdzaster]

yes there is a aftermarket block off kit...

Cool I’ll start looking . Than you sir.

 

[Douglasdzaster]

I'm plainly in agreement that fuel pump it's not attached to the lower carb, pics in post 16 shows it all. Must have clicked by mistake the Tohatsu 40 HP spare parts page which lives side of the Yam's 40 page. Let the one who has never had a senior moment to cast the first brick.....

Happy Boating​

Left to right. Top , middle, bottom. I found me and old style fuel tank that’s in good shape. I’m going to clean it up and use it. Still gotta pull the fuel pump and check the diaphragm as suggested. It doesn’t seem to be priming as tight as when I first fixed the fuel leak and I can’t find any other leaks unless it has to do with the new tank as well. Its getting tight just not solid like it was.

 

[Sea Rider]

Yep the plugs looks pretty even in color to me, seems the carbs and the electrical components are doing their homework right. If the fuel pump were with issues will need to prime the bulb constantly or the motor will die, not your case, right ? With a standard fuel line and tank prime the bulb with arrow facing upward till firm. A firm condition it's more than enough to fill all the carb's bowsl properly...

Happy Boating​

 

[99yam40]

the bottom(#3) looks a little darker than the top 2 which are white.
pin hole in the pump diaphragm will let extra fuel into #3 crankcase
that or #3 needle and seat not closing off completely could also
either of those will not let primer firm up completely

 

[Sea Rider]

the bottom(#3) looks a little darker than the top 2 which are white.
pin hole in the pump diaphragm will let extra fuel into #3 crankcase
that or #3 needle and seat not closing off completely could also
either of those will not let primer firm up completely

On 2 stroke 2-3-4 cylinder motors won't find the spark plugs darken exact same as with 4 stroke ones, one or 2 will differ from the rest. The OP has installed new parts inside each carb along adjusting float's height to specs.​

If opening the fuel pump will surely find both rubber diaphragms excessively ballooned or even dry, if still in good shape and removed for a close inspection the diaphragm's bolt's holes will probably won't fit any more specially if E10 fuels were used for a long time. Time to order 2 new ones at around $ 30.00, body gaskets at each side are not included.

Let's find out when the old style fuel hose, primer bulb and fuel tank are installed if able to prime the bulb till firm...

Happy Boating​

 

[Faztbullet]

On a 3 cylinder motor #3 will be a tad darker due it being supplied a lil extra fuel from recirc system to bottom bearing. Same way on a V-4 as #4 and #6 on a V-6.

 

[99yam40]

On a 3 cylinder motor #3 will be a tad darker due it being supplied a lil extra fuel from recirc system to bottom bearing. Same way on a V-4 as #4 and #6 on a V-6.

he still needs to figure out why the primer bulb does not get firm

 

[Faztbullet]

If it has no leaks internal or external, and is a aftermarket line or bulb most likely the primer bulb. I only use OEM bulbs as the aftermarket ones the check valve/s fail.

 

[Douglasdzaster]

I went all out on the fuel line and bought the A1-15 rated black marine line . Yamaha fuel water separator, fuel bulb is a Yamaha how ever it’s the second one because the first one came apart. I’ve been handling the replacement with kit gloves. It’s a $25 bulb and I’m sure Yamaha makes better. When I replace tanks I’m going to check all my clamps as well.
When I replaced the leaking motor fittings. With the hose off I squeezed the bulb then put my thumb over the hose and released the bulb. On the third time fuel shot out and I reconnected the hose. That’s when it primed up rock hard. It still pressures up, just not like it did then. I do hold the bulb with the arrow pointing straight up. This puts the bulb a little higher than where it flows into the engine without putting any kind of a bind on the hose and bulb at the bottom. Had my wife take a picture but instead it’s a short video. Let me know if you guys can see anything or not. I have the fuel hose protected with gorilla sleeve is why it looks like it does.

 

[Faztbullet]

Yer good as long as there are no leaks....bulb does not have to get/stay hard to run. Its only purpose is to prime carbs.

 

[Douglasdzaster]

Thanks to all of you for the replies and advice. I wouldn’t have gotten this far without this forum and all your help. I gotta build up the boat account a little more then go see the prop guy on a smooth day to test out what he’s got.