help trouble shooting

[tomanycars]

Hello everyone. I just joined this website because i bought 3 older jet ski's that do run. I better learn how these things run as they are all old. One of the machines does have a problem. 2000 seadoo 787 millennium edition rfi . First off a shop did install a new engine. The guy says it runs good for the first 5 minutes out then loses power for a few minutes then runs great the rest of the day. This has been going on for a couple years. But it does this every time it is put in the water . The shop thought it was the engine and that's why they had him spend 2800 on a new one installed. Still does it. He tried the rectifier , Didn't fix it. Any thought anyone. Did i mention this is a chevy 350 in a jetski.

 

[darren shumbo]

is it a 787 or a chevy 350 ? Dont waste our time on here please..

 

[etemplet]

I'd start with a fuel pressure check.
Check the rave valves to make sure they are working properly. Make sure the check valve on the rave line from the engine is functioning.
Remove the fuel canister and replace the fuel filters and get the injectors cleaned. Unless you can prove someone has done this recently I'd do it. Doesn't cost all that much. $60 for the injectors, $15 for the filters.

Then you can start on the electrics
Pull the AMP plugs on the MPEM and have a look. If you have not been around Seadoos if you are not careful with the latches that hold the AMP plugs tight you may breat them off. There are latches on either side of the plug and they simply release the plug. Don't use them as a gripping point to remove the AMP plug. Hole the Plug "top to bottom" and wiggle it. Sorry but the best I can describe.

Make sure the plugs and connectors are in good shape and clean. Download a repair maual and go through the process of checking the component resistance at the pins. I'd check all of the electrical connections for being clean and tight. That might not be your problem but it is a place to start.

You could start with the 3 wire plug on the ignition coil and the single black wire which is the ground. There is no way to know the source of your problem.

That's about 10 hours worth of work.

 

[tomanycars]

is it a 787 or a chevy 350 ? Dont waste our time on here please..

I wasn't getting any replys for a long time so i wrote that trying to get a reply . Thanks for playing dummy.