Slytly-Stok
New Member
Greetings - first time user of site - just bought first jet boat yesterday.
Well, I hope I didn't make a huge financial mistake, but I picked up a really nice condition 1997 Challenger 1800 yesterday for what I thought was pretty cheap compared to what I've been seeing lately. I knew going in it possibly had a diagnosis of a bad mpem. The seller assured me I could find a used one on ebay for under $500 and it would be good to go. My bad for believing that part about it being easy to find one on ebay, or anywhere for that matter - I accept responsibility for not doing my homework first.
Anyway, I'm just looking for some feedback cause I'm not so sure it's the mpem that is bad (at least hoping it's not!)
I did compression test - both engines have about 150psi on all cylinders. They both start right up. One sounds flawless. The other starts and runs but it has a slight misfire at idle, but when at mid range the misfire seems to go away. The seller was upfront and told me of all this and said that it just started doing it during his last couple rides of the year, but not all the time. He said once over 4000 rpm the misfire goes away and it runs fine all the way up to 7000rpm. I did not get to ride it on water - just started it on the trailer so i could hear it. I did hear the misfire/rough idling briefly, but then it went away within the minute or so we ran it. He said that's what it does - sometimes runs without a hitch, others it has the mis-fire down low. He took it to a sea doo dealer last month after he started observing the symptoms and they said the stators and rectifiers were good and that it "appears" to be a bad mpem?
I thought a mpem either worked or it didn't. My question - with the misfire just happening at idle and just on one engine, could this be a bad mpem or does anyone have some ideas on what else to look at before I start looking at replacement options for the mpem?
Thanks very much for any quality advice! Other than that I shouldn't have bought it withut testing it on the water first or buying it with an obsolete and never-to-b-found mpem replacement part...... i already beat myself up enough the last 24 hrs over that..
Well, I hope I didn't make a huge financial mistake, but I picked up a really nice condition 1997 Challenger 1800 yesterday for what I thought was pretty cheap compared to what I've been seeing lately. I knew going in it possibly had a diagnosis of a bad mpem. The seller assured me I could find a used one on ebay for under $500 and it would be good to go. My bad for believing that part about it being easy to find one on ebay, or anywhere for that matter - I accept responsibility for not doing my homework first.
Anyway, I'm just looking for some feedback cause I'm not so sure it's the mpem that is bad (at least hoping it's not!)
I did compression test - both engines have about 150psi on all cylinders. They both start right up. One sounds flawless. The other starts and runs but it has a slight misfire at idle, but when at mid range the misfire seems to go away. The seller was upfront and told me of all this and said that it just started doing it during his last couple rides of the year, but not all the time. He said once over 4000 rpm the misfire goes away and it runs fine all the way up to 7000rpm. I did not get to ride it on water - just started it on the trailer so i could hear it. I did hear the misfire/rough idling briefly, but then it went away within the minute or so we ran it. He said that's what it does - sometimes runs without a hitch, others it has the mis-fire down low. He took it to a sea doo dealer last month after he started observing the symptoms and they said the stators and rectifiers were good and that it "appears" to be a bad mpem?
I thought a mpem either worked or it didn't. My question - with the misfire just happening at idle and just on one engine, could this be a bad mpem or does anyone have some ideas on what else to look at before I start looking at replacement options for the mpem?
Thanks very much for any quality advice! Other than that I shouldn't have bought it withut testing it on the water first or buying it with an obsolete and never-to-b-found mpem replacement part...... i already beat myself up enough the last 24 hrs over that..
