99 Challenger accelerator pump question???

[jhjesse]

I am rebuilding my carbs and came across something I have not seen before. I went to blow out the small hoses and found one of the acc pump hoses blocked. So I stuck a small allen wrench in the hose to clear the obstruction and found this small brass "nipple" inside the hose. The "nipple has a small pin hole on one side and a larger opening on the other.
I checked the other set of carbs and they have the same "nipple" stuck inside the same hose.
Can anyone tell me what it is?
I cannot find anything in the manual or parts diagram showing this "nipple."

 

[Guest_User]

I am rebuilding my carbs and came across something I have not seen before. I went to blow out the small hoses and found one of the acc pump hoses blocked. So I stuck a small allen wrench in the hose to clear the obstruction and found this small brass "nipple" inside the hose. The "nipple has a small pin hole on one side and a larger opening on the other.
I checked the other set of carbs and they have the same "nipple" stuck inside the same hose.
Can anyone tell me what it is?
I cannot find anything in the manual or parts diagram showing this "nipple."

View attachment 18355View attachment 18356View attachment 18357View attachment 18358

that looks like a restrictor jet of some kind. it comes from the fuel source to the pump diaphragm housing? is there still a check valve in the hose to the squirter by the choke plate? I`m wondering if this restrictor prevent flow back and keeping the accel pump housing fuel of fuel for on demand.

I`ve changed all my hoses and didn`t even know they were in there. ran 21 plus hours since the 98 carbs were rebuilt using tygon, and now switched to blue poly for this year... I haven`t noticed any kind of problem without them...

maybe Doc Honda could shed some light on this...

 

[Guest_User]

ok I found it, it`s called a recharge jet part number 59 here:
http://www.sea-doopart.com/oemparts/a/sea/500cf604f870021b3c6a7e6f/carburetors

awww crap, they are supposed to be in the 98 as well, and I know they are not in the hose now...

I wonder what are the effects of not having these in place???

the boat has 21 hours with no running or accelerating issues...
awe crap...

 

[Guest_User]

found this searching the forum: sorry for the thread jack jhjesse...

That little part is called a JET-RECHARGE part # 270500348 it restricts how fast the accel pump can "recharge"

from PWCToday


WHAT IT IS: It is called a "Recharge Jet" (p/n 6505-975), and applies to certain accelerator pump equipped engines. It was covered under Service Bulletin 99-03W.

THE PROBLEM: As the throttle is closed, the accel pump sucks in fuel for the next squirt (for when throttle opens). When the fuel was drawn by the accel pump, it was strong enough to upset the delicate pressure balance in the carb diaphragm chamber, and affected driveability. Basically it sucked fuel too hard and fast.

THE FIX: Places a restriction (jet, orifice, restrictor) in the fuel supply line TO the accel pump. It does NOT go on the discharge side of the accel pump. That's why it is called a recharge jet, it controls the rate of recharge of fuel to the accel pump. This is a brass fitting with a small through hole. It does not have any checking properties. Look for dirt if it does act like this. The little critter is just slipped inside the hose, like a barb.

more:

No, it doesn't help it accel faster or eliminate hesitation.

Based on where it was to be installed, I would figure that it will affect the carb anytime you release the throttle. That's when the accel pump draws more fuel, and could cause the fuel from flowing into the mixing circuits on the carb (where you want it all the time). Without the jet, you may find a stumble on decel from higher rpms, and perhaps stalling from low rpms. The service bulletin mentioned 'poor low speed performance".



For hesitation issues, there is a very small recharge jet in black line from rear carb body to accelerator pump. Its just pushed in the rubber line as a restrictor. I have been told this is a check valve, but every one I have seen is just a small jet with 0.035" hole. These will get garbage in them just like any other part of carb. So something to check out. If these lines have been replaced, its possible the small jet was left off.

 

[jhjesse]

Great info Pale Rider.
I checked the diagram several times and didn't see the little sucker. I see it, now that you pointed it out. I guess I'm getting old. LOL

I am not sure if I should reinstall it or just leave it out. Doesn't seem to affect the performance on you boat and sounds like the "recharge jet" just gets clogged after a period of time. hmmmm...
I am going to check the other line as well.
Maybe I could leave them out and try it. They are super easy to reinstall if my boat doesn't perform well.

What do you think??

 

[Coastiejoe]

I would clean an reuse it as ifnitnis getting clogged, it is stopping whatever is clogging it up from getting to the carb and screwing the carb up.

Not intended as a filter, but seems to be one.
Clean fuel is pretty important as far as carbs are concerned.

It is easier to clean tenor face than it is to remove the carb,,,,

 

[Guest_User]

Great info Pale Rider.
I checked the diagram several times and didn't see the little sucker. I see it, now that you pointed it out. I guess I'm getting old. LOL

I am not sure if I should reinstall it or just leave it out. Doesn't seem to affect the performance on you boat and sounds like the "recharge jet" just gets clogged after a period of time. hmmmm...
I am going to check the other line as well.
Maybe I could leave them out and try it. They are super easy to reinstall if my boat doesn't perform well.

What do you think??

To be honest I wouldn`t have even known hadn`t you mentioned this thing stuck in the hose. So it made me look and do a little research...(thank you) Before I had no reason to research this recharge jet as I was rebuilding the carbs. My carbs were really clean and the boat ran "ok" with the old engines (well I guess as well as it could). I understand it`s function. I also understand that there is very little volume of fuel in the metering/diaphragm section of the carb. I also understand that when the accelerator pump needs to refill upon expulsion it could draw the fuel away from the Carb`s interior volume.
BUT,,, in the last 21 hours of use I have no complaints or directly related issues as a result of this recharge jet being out of the small hose.
I`m guessing that anyone with a driveability issue would investigate why the accel pump doesnt squirt and discover what you did. I didn`t have any issues with the accel pumps, and just replaced the diaphragm when rebuilding the carbs, and the hoses bc they were 14 years old. I`m not to concerned with anything clogging that hose/hoses as I`m running Racor fuel water separators now, and even still ran new regular filters last season.
I could see where this may be an issues with "ON/OFF" throttling in a jet ski, but have no real comparison to absolutely report. With the boat I throttle up and plane out and away we go until we slow down and accel again or come to a halt.
so I`m thinking it`s not disrupting the fuel supply inside the carb. My thoughts are while your engine is running fuel pressure is being made. I also have High Volume Mikuni fuel pumps that replaced the OEM units and maybe that could help, I don`t really know. So far this hasn`t been an issue for the boat...

as long winded as that reply is I hope that helps somewhat.:facepalm::lols:

note: I do have the check valves in the line from accel pump to discharge nozzle.

 

[jhjesse]

To be honest I wouldn`t have even known hadn`t you mentioned this thing stuck in the hose. So it made me look and do a little research...(thank you) Before I had no reason to research this recharge jet as I was rebuilding the carbs. My carbs were really clean and the boat ran "ok" with the old engines (well I guess as well as it could). I understand it`s function. I also understand that there is very little volume of fuel in the metering/diaphragm section of the carb. I also understand that when the accelerator pump needs to refill upon expulsion it could draw the fuel away from the Carb`s interior volume.
BUT,,, in the last 21 hours of use I have no complaints or directly related issues as a result of this recharge jet being out of the small hose.
I`m guessing that anyone with a driveability issue would investigate why the accel pump doesnt squirt and discover what you did. I didn`t have any issues with the accel pumps, and just replaced the diaphragm when rebuilding the carbs, and the hoses bc they were 14 years old. I`m not to concerned with anything clogging that hose/hoses as I`m running Racor fuel water separators now, and even still ran new regular filters last season.
I could see where this may be an issues with "ON/OFF" throttling in a jet ski, but have no real comparison to absolutely report. With the boat I throttle up and plane out and away we go until we slow down and accel again or come to a halt.
so I`m thinking it`s not disrupting the fuel supply inside the carb. My thoughts are while your engine is running fuel pressure is being made. I also have High Volume Mikuni fuel pumps that replaced the OEM units and maybe that could help, I don`t really know. So far this hasn`t been an issue for the boat...

as long winded as that reply is I hope that helps somewhat.:facepalm::lols:

note: I do have the check valves in the line from accel pump to discharge nozzle.

So when I get home this afternoon, I will examine the lines from the accel pump to the discharge tube and make sure they are there.

Pale Rider,
Did you change fuel pumps because the old ones were not working, or did you do it mostly for reliability?
I'm thinking about changing mine just so I don't have issues down the road. (or river)

Many Thanks

 

[Guest_User]

So when I get home this afternoon, I will examine the lines from the accel pump to the discharge tube and make sure they are there.

Pale Rider,
Did you change fuel pumps because the old ones were not working, or did you do it mostly for reliability?
I'm thinking about changing mine just so I don't have issues down the road. (or river)

Many Thanks

the old ones worked when I tested the boat before discovering what a real POS it turned out to be prior to all the new work. I heard that there weren`t any rebuild kits avail for the OEM pumps. The pumps being 14 years old, I mean how much longer could they last. with all the work that was done to the boat it just made sense to do something with them... My Friend Bill (may he RIP), rebuilt carbs, and modded them and was a dealer for Mikuni, so he got me 2 high volume dual outlet pumps and I changed the fuel hose routing to one outlet per carb... so far so good, and I never persued anything else with the OEM`s (which by the way are made by Mikuni also...

I`m surprised no one has jumped in to this conversation about the recharge jet...:willy_nilly:

 

[jhjesse]

the old ones worked when I tested the boat before discovering what a real POS it turned out to be prior to all the new work. I heard that there weren`t any rebuild kits avail for the OEM pumps. The pumps being 14 years old, I mean how much longer could they last. with all the work that was done to the boat it just made sense to do something with them... My Friend Bill (may he RIP), rebuilt carbs, and modded them and was a dealer for Mikuni, so he got me 2 high volume dual outlet pumps and I changed the fuel hose routing to one outlet per carb... so far so good, and I never persued anything else with the OEM`s (which by the way are made by Mikuni also...

I`m surprised no one has jumped in to this conversation about the recharge jet...:willy_nilly:

I cleaned the recharge jets up and reinstalled them. I will get the carbs back on in a couple days and try it out. I will let you know how it comes out.
Now I am thinking about getting a couple fuel pumps. I just want this damn thing to not give me any problems. I have a 28yr old daughter that has cancer. It would be so great to take Her and Her Husband out on the boat this summer and not worry about something breaking.

 

[Guest_User]

I cleaned the recharge jets up and reinstalled them. I will get the carbs back on in a couple days and try it out. I will let you know how it comes out.
Now I am thinking about getting a couple fuel pumps. I just want this damn thing to not give me any problems. I have a 28yr old daughter that has cancer. It would be so great to take Her and Her Husband out on the boat this summer and not worry about something breaking.

We are truly sorry to hear that your daughter has cancer. We hope she can return to good health very soon. Your Daughter and Family will be in out thoughts and prayers.

I`m not sure if there is a volume test for these like there are with automotive pumps. It would be your call to replace the pumps. I`m not sure the OEM`s are avail. I would think they would be. I knew before hand that I was going to plug the carb fitting T ,feeding the PTO carb and use one outlet/supply per carb. from the dual outlet pump, rather than plug a supply port on the pump itself.
take a look back in the boat build at the hose orientation from the pump to carb to see what I`m referring to.

I feel that the fittings are fragile bc of age and also used a lighter poly (or tygon) fuel hose at the carbs only. The PO had an issue with one of the plastic T`s in the return circuit breaking off and I`m sorta stuck with what I have...
My intention was to get all new carbs, but none are avail as a direct replacement. There are new carbs avail but would require extensive jet changes, internal fuel pump removal using my existing supply plates to keep the remote pumps...
as long as ours are working efficiently I`ll maintain them and hope for the best... but I`m pretty sure at some point I`ll have to replace them and adapt if I plan on keeping the boat any length of time...

one good thing is that we have 2 engines and can come back on one in the event something happens out on the water. This already happened to us 2x and it takes forever to come in from 6 miles down river...wow...

man I`m such a bozo for not realizing those recharge jets were in those small hoses, eh live and learn...:facepalm:

 

[Coastiejoe]

I cleaned the recharge jets up and reinstalled them. I will get the carbs back on in a couple days and try it out. I will let you know how it comes out.
Now I am thinking about getting a couple fuel pumps. I just want this damn thing to not give me any problems. I have a 28yr old daughter that has cancer. It would be so great to take Her and Her Husband out on the boat this summer and not worry about something breaking.

If you don't get the boat running right you let us know. We will find a way for you and your family to enjoy the time you spend together and not worry about the boat.

I'm serious.....

 

[jhjesse]

Many thanks Guys. My family and I are fighters and we never give up. When we beat this thing I am going to have some T-shirts made that says "We kicked cancer's Ass." Then I am going to pass them out anyone that wants one. I'll save a couple for ya.

Water Craft Super Store has Mikuni fuel pumps on their web site. Might give them a call tomorrow.

 

[jhjesse]

So I called WCSS this morning and the high volume fuel pumps they sell are, if fact Mikuni brand.
They should be here next week.

 

[Guest_User]

dual outlet? you`ll need to fill one outlet with JB weld or suitable epoxy and cap it, if your going to use the factory hose routing.
you`ll need to drill and tap the fuel pump mounting bracket as well for the wider/longer bolt pattern. be careful where you place it so it doesn`t hit the tuned pipe. take a look at the pics in my build thread to get an idea...

 

[jhjesse]

dual outlet? you`ll need to fill one outlet with JB weld or suitable epoxy and cap it, if your going to use the factory hose routing.
you`ll need to drill and tap the fuel pump mounting bracket as well for the wider/longer bolt pattern. be careful where you place it so it doesn`t hit the tuned pipe. take a look at the pics in my build thread to get an idea...

Yep I knew I was going to have to do some modifications. Even though you mounting location is different, it gives me some good ideas as to where I can locate the pumps. Probably going to be a Fall project since the current pumps seem to be working well.

One set of carbs done and installed. Going to try and get the other set completed before I travel (work) Sunday.

 

[jhjesse]

So I got it all put back together and waterhose tested the engines. All is well so far, but I had to go out of town for a couple weeks, so no lake test yet.
Ordered a new throttle cable for the right engine. The right cable threads broke while I was reinstalling it on the carbs of the right engine.
I over tightened the damn thing. Stupid move on my part. Managed to get it installed temporarily until the new cable arrives.

So far I have rebuilt the jet pumps with new wear rings.
Changed the fuel filters and oil filters.
Rebuilt the carbs with new needles and seats
Lubricated the all the cables.

Things left to do:
Fix the fuel sender.
Install new throttle cable.
Repack wheel bearings and modify trailer tongue.

Next Winter projects include:
New Fuel pumps - already have them.
Upholstry

 

[kilgorekb]

The PO had an issue with one of the plastic T`s in the return circuit breaking off and I`m sorta stuck with what I have...

I broke 1 leg of my 1/4'' T as well. I'm going to just seal off the broken side and add an external T unless someone has a better idea. I'd like to replace it, but doesn't look like this is a replaceable part. Can someone tell me what sealant I should use?

Also, does the orientation of the recharge jet matter? I'm guessing the tapered side goes toward the accel pump.

 

[noswal_j]

The recharge jet's hole diameter is the same on both ends. The taper is just to help with installation. It can be installed in either direction.

 

[Guest_User]

I broke 1 leg of my 1/4'' T as well. I'm going to just seal off the broken side and add an external T unless someone has a better idea. I'd like to replace it, but doesn't look like this is a replaceable part. Can someone tell me what sealant I should use?

Also, does the orientation of the recharge jet matter? I'm guessing the tapered side goes toward the accel pump.

I spoke to a carb rebuilding company that specializes in mikuni carbs and the service manager said those plastic T`s are not avail. Seems they are only on the boats.

what the PO did, was ship the carb out, had the machine shop size and install a mikuni 90° fitting in it`s place. hence why I have a brass T fitting on that engine only for the fuel return circuit.

 

[kilgorekb]

Those blue lines look sharp! I'm going to install the yellow tygon this weekend. What are the blue ones made of? Got a part#?

 

[jhjesse]

Those blue lines look sharp! I'm going to install the yellow tygon this weekend. What are the blue ones made of? Got a part#?

http://www.watercraftsuperstore.net/Sea-Doo-PWC-Fuel-Line-Filters-Primers.html