951 Exhaust Removal

[4Run4Fun]

Hi guys,
I'm about to do a fuel line replacement on a 951. I've searched the forums for a procedure to remove the enormous head pipe that blocks the carbs. Oddly, I have found people mention in other posts about other procedures that its easier to remove the exhaust once the carbs are removed. That seems strange since I was planning on removing the exhaust to GET TO the carbs. Can someone shed a little light on this for me. Should I try to get to the carbs with the pipe in place, or should the pipe be out? Its like a catch 22, each item is easier to remove once the other is out.
Thanks,
R

 

[cdnbikerdude]

You don;'t need to remove the pipe to change the fuel lines or carbs.


It is not advisible to remove it either unless you are taking the entire engine out.

 

[4Run4Fun]

Thanks for the reply,

I assume that if I am not removing the pipe, then all the carb bolts will be accessible from topside. Some seem to be obscured from sight, but I guess if you say it can be done, then I'll try it. Any tips/tricks would be greatly appreciated. I've done several 650s and 717s, but this 951 is a different animal.

Thanks,
R

 

[cdnbikerdude]

4 allen bolts to remove and it pops right off. You just use a small socket wrench ...

If you get the shop manual from above it will show you where they are located.

 

[4Run4Fun]

Thanks again for the reply.

I'm assuming you mean 4 allen bolts on the carbs (not the head pipe). Is that 4 per carb, or 4 total - 2 per carb?

Thanks,
R

 

[cdnbikerdude]

Just 2 per carb. You can see the top two already even with the pipe in the way. The other two you will have to feel for.

 

[4Run4Fun]

Got it!

I plan to get started this evening, so thanks for the heads up. That should make the job a little less work - by leaving the pipe in place.

Thanks,
R

 

[nerdlinger]

You don't need to remove the pipes, and you would need to remove the carbs to get to that crazy nut on the bottom side of the pipe anyway, unless you have a special tool to get at it. You will see what I mean when you look at it.

The carb bolts are diagonal from each other - top left to bottom right. The bottom ones ( the ones you can't see) are recessed a bit deeper than the top ones. After you get the air intake off you should be able to get a mirror and flashlight in there to help you find it.

I think it is a 5mm allen wrench. Depending on your allen wrench lengths, you may need help in loosening the bolts on the bottom since they are tougher to get to. I just finished replacing my fuel lines, and I attached a 3/16 socket head to the end of the allen wrench, then used a socket wrench to help turn it. The socket wrench was essentially just an extension of the allen wrench handle.

 

[4Run4Fun]

Excellent reply!
Thanks for the details. If I may ask, did you remove the carbs still attached to each other with all the linkage? This is normally what I do for the 650s and 717s as it keeps me from having to remove and reattach all that linkage. If you did remove them together, do they fit out from under the pipe towards the front of the boat or rather towards the rear? Is the pulse line connected to the MAG carb as it is on the smaller Rotax engines?

Thanks again!
R

 

[cdnbikerdude]

They come out together in one piece. When you have them on the bench you can take them all part to clean em' up.

 

[nerdlinger]

They come out as one piece, as bikerdude said. There should be three fuel lines to the mag carb if I remember correctly: one to the fuel tank, one to the fuel filter, and one to the engine. Two of them are 6mm hoses (1/4 inch), and one is 8mm (5/16 inch). The size of the fittings on the carbs will give it away if you are unsure. I replaced one line at a time to avoid any confusion.

Are you replacing just the lines that run to and from the carbs, or are you replacing everything, including those at the tank and to the fuel selector?

 

[4Run4Fun]

I am doing them all. No grey lines will be left inside the boat. I have completed this procedure mulitple times, but never on anything larger than a 717.

I think the 3 lines are 1 - feed line from fuel selector 2- return line to tank 3-pulse from crankcase to operate diaphram pump ( no fuel is actually in this line)

Thanks,
R