3 replies to this topic

[BigArm]

So, I am fairly new to Sea Doo watercraft/boats, but I getting hands on experience and learning quite a bit from the forum. I have a 97 Challenger 1800 that has the usual "one engine keeps fouling" problem. In this case it is the port side engine.
Maybe I should back up a bit. I bought the boat this fall from a man who readily admitted it kept flooding one engine. The local Sea Doo shop recognized this boat and said, yes it has problems and keeps fouling the plugs in one engine after running for some time. I purchased the boat with this knowledge. Winter is arriving in Montana, so at this point I have only been able to check compression in the engines and put sta-bil in the fuel. Then I backed the boat into the local river and briefly ran the engines. Well, both engines run, compression in all four cylinders runs 138-145. Upon inspecting the suspect engines carbs, I noted the previous mechanic had left out several bolts here and there (bolts holding the intake sound suppressor and spark screen in place. Nothing noted yet missing on the carbs themselves; except the mag side choke butterfly was not clamped to the choke cable. When I pulled the choke, only the pto side choke butterfly closed. I tightened the mag butterfly to the cable and now they both close. Supposedly both engines would run for a while, then the port engine would load up and foul the plugs. Has anyone had experience, or could anyone give an educated guess as to the possibility of the mag butterfly being sucked partially or fully closed during engine operation and fouling that cylinder.
It seems to me that airflow though the carb body would have roughly equal pressure on either side of the butterfly and keep in open, but I really need to put the boat in the water and test it; something that will have to wait until spring.
Otherwise my winter projects include removing both tuned exhaust pipes and repairing the leaking plug on the bottom of both. I have seen great threads on this. I also will likely remove the offending carb and test it according to the manual. The 99 Sea Doo watercraft manual my parents have; which while addressing the same engine does not address the settings for the Challenger boats.
If anyone can give me carb model and settings for the Challenger, it would be helpful. Thanks, James

[seadoofanatic]

While I don't know the specific carb model and setting for your boat it might be worth downloading the shop manual, http://seadoosportbo...00-shop-manual/. The manual might provide this information you are looking for.

[BigArm]

While I don't know the specific carb model and setting for your boat it might be worth downloading the shop manual, http://seadoosportbo...00-shop-manual/. The manual might provide this information you are looking for.

Thanks; I do have the 99 PWC Sea Doo Shop Manual and it covers the 787 engine in detail. I plan to overhaul the carbs this winter. James

[BigArm]

Thanks; I do have the 99 PWC Sea Doo Shop Manual and it covers the 787 engine in detail. I plan to overhaul the carbs this winter. James

An update on the winter project. I did procure the jetboat manual. I have finished repairing the leaking tuned exhausts and will install them shortly. In the throttle assembly the port throttle stick easily drifted back after being advanced. I removed the assembly and tensioned it. The front convienience light (footwell in the open bow) does not work. Light is ok -no power. Anyone have to repair the wiring harness to that light fixture? Otherwise I believe I will leave the port carbs alone and fire it up in the spring and see how it runs. James