mjb

I have 2 MEFI 1 502 MPI's. I have been servicing my injectors and replacing them a few at a time(with used ones) for the last 3 years. Everything else on these engines is new except the injectors...and now another on just went bad.
I need NEW injectors....all 16 to give me piece of mind.
Mercruiser wants almost $150/ ea. I know that these injectors were(still are??) made by Keihin. The mercruiser part # is 805225A1.
Does anyone know what the Keihin part # is?? Can I buy them directly from Keihin for a more reasonable price?? I have had no luck.
Thanks-

t500hps

contact injector.com (marren fuel injection). I bought 16 from them last winter and they treated me VERY well.....for 540/500EFI's mine were less than 1/2 what you quoted.

kennyo

It's winter time. Pull all of them and have them serviced. I used Witchhunter injector service off the internet. They were very reasonable.

mjb

I have had them serviced every winter for the last 3 years. Every year a few more need replacing....and this season one went bad during the summer. Most places only flow and clean them during servicing. They really don't do electrical resistance testing etc..
My thinking is that they are old and worn out and I just need new ones so I don't have to deal with this every season...not to mention the risk of loosing a new engine when one goes bad in mid season.
Thanks for the lead to injectors.com I have contacted them to see if they can help.

Alex

Interesting subject since I'm convinced injector service should be made on regular bases with regards to the flow volumes and working environment.
No shop inte the boating business in this country have brought this up, except me.
I'm still trying to figure out how to convince customers to pay for the labour, mainly for having them removed and put back again. They mostly don't realize what potential problems could hide behind a malfunctioning injector, unfortunately the engine control unit won't tell either.

t500hps

Alex, I built (mostly with a buddies help) a pair of 540/500EFI's this past winter. Everything was perfect except 2 of the injectors quit pumping past 3/4 throttle.....2 hours after the motors were running one came apart!!!! You are correct in that even with fuel pressure guages and any other system monitors you may have, a bad injector cannot be diagnosed while in the motor.

mjb

When I re plumbed my fuel system with these new engines, I installed isolation valves on the supply and return lines(to tank) along with a mechanical pressure gauge on the rail. If I turn the engine off and the gauge drops quickly, I can close the valves and determine whether it's an injector going bad or whether it is bleeding back thru the pump or the return regulator.
The first time it happened I thought it was a bad injector but when I closed the return line shut off valve, the gauge stopped dropping...that told me I had a defective regulator...not a bad injector. This time the gauge still drops with both valves shut so I know it has to be bleeding off thru a bad injector.