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[Mypoorfudge]

Hi guys, looking for a bit of help here.
I got my FJ12 running after about 6 years last sunday. I had set up a temporary gravity fuel tank and bypassed the pump.

I did have a leak at the plastic T piece of the fuel inlet to the carbs. This I sorted and the bike ran ok.

I put the pump and tank in this evening and. THe pump is not original but was on the bike when I got it and it works fine.

However I have petrol coming out everywhere. I seem to have petrol coming out of the vents see the pic below. THe first pic is between carbs 2 and 3.

I do not have a pipe coming off this vent, should I have ? and where does it go.

The second pic is hard to make out but is between carbs 3 and 4. There is a plastic T piece in there and a tube coming out of the bottom to nowhere. Where should this go.

Any help would be really appreciated.

[Urban_Legend]

As far as I can tell all of the locations indecated are for the airvents and overflow pipes. It soouds a lot like you may have stuck fuel floats which will allow the float bowls to over fill and the bike has a bad nervous wee issue. Happens more than we like to admit. You said the bike has not run in quite a while, so there could be some crud in the float bowls gumming up the works.
The fix is to remove thar carb and clean.

From memory there shold be 6 pipes, 4 breather lines and 2 overflow (apart from the fuel lines) that come off the carb and run to just behind the motor.
Mark

[Mypoorfudge]

Thank you Mark for the reply.

I have searched for some pictures of what all these pipes should look like and where they go but have had no luck. The Haynes manual has some vent system shown but I reckon that is a different model than mine (3CV).

So with the floats stuck I am basically pumping petrol straight out of the vents .

[oldktmdude]

   While you're in the carbs, check the "o"rings on the float needle seats. They are notorious for leaking when a bike has been sitting for a length of time.
   Regards, Pete.

[Mypoorfudge]

Thanks Pete. Will check those.

The Australians to the rescue. By coincidence im off out tonight with a bunch of guys from Perth

[Pat Conlon]

Hey Mike, buy and install this kit:
 http://rpmracingca.com/proddetail.asp?prod=carbkit




The best $22 you will ever spend...bar none.

[Mypoorfudge]

Hi Pat, I had gone through all the small o-rings last september and replaced them. Nearly all of the screws were changed to stainless by the previous owner.

I found this thread on the forum.

http://www.fjowners.com/index.php?topic=16920.0

One thing strikes me about the photos. The fuel is fed in at two points. I only have one feed into the carbs, between 1 and 2. There is a hose coming out of the T piece between 3 and 4 but goes nowhere.

Does anyone have a picture of what a european/UK spec 3CV looks like.

I did remove the carbs again and cleaned everything. Nothing really in there only some small bits of dirt. After installing the carbs again, I still have fuel being pumped out of the vent.

I just got depressed then and walked away from it.

Any help is appreciated.

[Pat Conlon]

The fuel pump FJ's ('88-95) have one fuel inlet, (a T) in the center between #2 and #3

The gravity flow FJ's (84-87) have 2 fuel inlets (2 T's)
One T is between carbs #1 and 2
The second T is between carbs #3 and 4

So...if you have only one fuel inlet and that inlet is between #1 and 2, something's wrong.
it sounds like you have gravity flow carbs on your fuel pump FJ, and you have one T missing or open.

Additionally, there is a difference in the size of the float needle seats between the fuel pump carbs and the gravity flow carbs. The gravity flow carbs uses a larger opening on the float needle seat, the fuel pump uses a smaller opening. This is due to the higher fuel delivery pressure of the fuel pump.
If you have the larger gravity flow float seats....and a fuel pump, the higher fuel pressure from the fuel pump will force the float needle off the seat and you will have a gusher.
Something to think about.

[Mypoorfudge]

Thank you Pat for your reply.

All is sorted now. A combination of your reply and a conversation with a friend about this issue has given me the answer.

Basically I had the plumbing in reverse. I had the pump connected to the vent and nothing connected to the inlet as you can cee in the top photo above.

When I stripped this bike 6 years ago I took hundreds of photos of the process. I still have those photos but for whatever reason I only started taking them after I removed the carbs.

I had no idea of how to plumb the carbs back in and every manual out there only shows different carbs, not the 3cv.

Your comment that the 3cv has only one inlet and my friends suggestion that the inlet would be metal and the vent would be plastic opened my eyes.

Bike is running well now and even had a run up the road yesterday evening.

[Urban_Legend]

Excellent news. Glad she is on her way to being sorted.
Mark