97 Challenger engine trouble

[M_Packert]

Hello Forum

We are two newbie’s who acquired a SeaDoo Challenger 97 in bad shape as a fix up project.

The workshop manual was the first thing we got after the boat – one is a auto mechanic and I am a electronic engineer, so we had confidence starting out, but after more than 10 outings we are low in spirit….

We need help getting the engines running right….

Engine 1:
Difficult to start – almost drains the batteries trying, but runs well when started, revs well too – if we turn it off in the water for more than 2minnuts it won’t start again!

Engine 2:
Starts easy, but can’t rev above 4000rpm

The oil pumps is bypassed by the previous owner so we premix fuel and oil 2% is that right?

The RAVE valves had some melting damage on the plastic tops, so we replaced the bellows and adjustment cabs. Further more we have cleaned the carbs, the fuel tank and all the filters

Any ideas to get the engines running before the end of the season her in Denmark – Please?

/Michael

 

[kustomkarl]

Welcome to the seadoo forum Michael. I would check the wires from the battery and special attention to the ground to the engine by the starter.Be sure it is clean and has a good connection. I would do a compression test so you now what is going on internally. The compression ideally should be at 150 psi. If you are premixing your oil and fuel than the proper ratio is 40:1.

Keep us posted on you progress.

Karl

 

[timmyboy76]

Congrats on purchase M_Packert....i'd double check the carbs again, even being cleaned, dont mean their good..(diaphram, needle and seat-n/s..etc). Being 11-12yrs old, i'd rebuild them, and if so, pay close attention to the pop-off pressure and after full assy, carb pressure...assuming ur boat is equivalant to these specs...MAIN-142.5 PILOT-70 1.5n/s 23psi - 43psi LOW(lsa)- 1 HIGH(hsa)- (MAG-0 PTO-1/2)...good luck

 

[M_Packert]

Please explain the last part, it is a little to technical for me to understand…?

 

[seadoosnipe]

Carbs.........

First, you sound like you need to open the low speed screw, on both carbs, just a 1/4 turn.

Second, your carbs use an accelerator pump. The accelerator pump is used to give a squirt into the throat of the carbs, this creates initial vaucuum response to the engine, then as you increase the throttle, engine vacuum will completly take over, drawing fuel from your main jets.

When the air box is removed, you need to squeeze back on the throttle (put it in gear first) and watch to see if the pump is squirting fuel into the carbs through those nozzles (they are about 2 o'clock in the throat and made of brass). You can just grab the linkage bar and do this, you don't have to have somone up front while your working on the boat.

With the air box removed, you can see this pump on the side of the PTO carb. There are two little brass nipples sticking into the sides of the carbs, about 2 o'clock. They gum up real easy. So, get some carb cleaner, with the little red hose attached and give it a quick squirt in each one to make sure they are clear. Look inside the carb while you do this, cause you don't want to much of this getting into the engine.



You can see this accelerator pump layout in our parts link above. Just click it open, choose your boat and year, then select carb. You'll be able to get an idea of what your looking for.........good luck.:cheers: