1997 GTX MPEM Question

[Holt]

I recently purchased an aftermarket Arieltek MPEM for my 1997 SeaDoo GTX, at a savings of over $750 CDN funds, over and above the Bombardier unit. The 5 amp was blowing . Did all the diagnostics that I could based on info from the net. I am not that technical. Plugged the new MPEM in and the machine fired right up, in the driveway. Only function lost, and I was made aware of it up front, is that the DESS function is now disabled and the machine will start with any key. Have yet to put in the water.

Question 1:

The manual for the new MPEM says that it is programmed to operate hand in hand with the
engine timing set to -4 degrees (based on the #8 stamping designation on block beside serial number plate) whereas my engine is
currently set at -1 degrees (based on the #5 stamping designation on my block).
Will this cause a problem / cause damage to my machine, if I do not have the timing adjusted? If no damage per se,
with the timing off / retarded by 3 degrees too much, from a performance
view point, would this effect either the "out of the hole" or "top end"
performance?


Question 2:

The engine now idles @ 3000 r.p.m. Will this be a problem or should I wait to see what r.p.m. is with machine in water? And if still @ 3000, should it be adjusted down and if so, to what r.p.m.?

Any and all help would be greatly appreciated!

 

[Dr Honda]

3 degrees retarded is ok, and won't hurt anything. But you are probably going to notice it as it accelerates, and there will be a loss of a hundred (or so) RPM up top.


Get someone to change it's advance point to get full power.

 

[hotrodssnova]

I was going to ask if it could be tuned. ..The timing curve. Usually in the car world, aftermarket ecus can be tuned.

 

[Holt]

I am unfamiliar with "changing it's advance point to get full power". What does this mean and can you direct me to a "how to" link?

Much appreciated!

 

[Dr Honda]

I was going to ask if it could be tuned. ..The timing curve. Usually in the car world, aftermarket ecus can be tuned.

The MPEM isn't an "ECU". It doesn't control the fuel, or ignition tables. It's basically just a smart switch box. (turning on power, and adding security)

I am unfamiliar with "changing it's advance point to get full power". What does this mean and can you direct me to a "how to" link?

Much appreciated!

On the 800 engine... the pickup coil is fixed. So... to give the proper ignition starting point to the CDI unit... the MPEM needs to know where your engine is set at. In your case, -1 degrees. So... you plug in to the MPEM with a BUDS system (or aftermarket computer) and you simply tell it.

With that said... I have no idea if the aftermarket MPEM's can actually be changed.




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