2000 Pro Air Nautique, PCM 5.0 HO, Fuel Delivery Issue

[comanche344]

Hello All,

So I recently purchased a 2000 Pro Air Nautique. It has the PCM 5.0 H0 275HP engine. Owner was having issues with starting (spark, engine turns over, but no boom). I currently believe it might be a fuel delivery issue. After testing the kill switch works (found to be common issue), I found the following:

1. Fuel Pump Relays - One for the high pressure pump, one for the low. How do I test them? This could be the cheap fix.

2 x https://www.nautiqueparts.com/produc...p-tbi-r130012/


2. Low Pressure Pump - Only found a couple gas lines and a power cable (Currently disconnected, pic attached). I ran 12v power to this pump and got nothing.

https://www.nautiqueparts.com/produc...-pcm-ra080018/


3. High Pressure Pump - When I opened the Fuel Control Cell which has the pump in it, I found a mess. No filter, and the power cable was missing a lead (pics attached). So I believe I have 2 options.

1. Purchase a complete FCC from the link below.
https://www.nautiqueparts.com/produc...part-ra080031/

or

2. Purchase the following items and refresh the FCC I currently have.

https://www.nautiqueparts.com/produc...part-rp080026/
https://www.nautiqueparts.com/produc...trol-cell-fcc/
http://www.skidim.com/KIT-FCC-PASS-T...info/RF121085/
https://www.nautiqueparts.com/produc...pcm-ra080025a/
http://www.skidim.com/HOSE-KIT-FCC-H...info/RK045098/


What do you guys think? Let me know if there is anything I am missing.

- David

PS: Nautiqueparts also sells this complete retro kit (below), but I'm trying to narrow down the problem first.

https://www.nautiqueparts.com/product/retro-fcc-kit/

[2000superdare]

When the boat is powered on and ready to start the low pressure pump primes the high pressure in the fuel cell, you should here a buzz. If you have it out put 12 volts to it, it should make some noise if not replace. High pressure connections should be cleaned up, needs a new filter canister o-ring and should replace the rubber house going from pump to the spin on top. skid.com should have all of that. I would replace the relays since they are cheap and always goo to have extras. Some boats had an inline fuel filter as well worth a look.

[comanche344]

Hi,

Thanks for the advice. Where should I look to find the inline filter?

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[2000superdare]

Not sure exactly mine does not have one but I have heard of some that do depending on year/model. There is a whole right up on these motors on a forum somewhere I believe its called "the poor mans gt40 diagnosis" or something along those lines, lots of useful info there.

[teamseal]

that looks like a whole lot of mess right there! To much crud to be an effective fuel delivery platform. I would rebuild from the bottom up that fuel system then see if you have any electrical circuit issues.

[DW SD]

What is the tank like? If you have all that varnish in the fuel pump I would evaluate everything upstream too.

Well the injectors are probably plugged too. I’d expect the whole system to need cleaning and or restoration.

There are two relays operating in series. The first turns on the engine computer (ECM). The computer outputs a ground trigger to terminal 85 of the trigger circuitry on the second relay.
86 of the same relay is 12V+ from switched ignition.

Terminal 30 is also switched 12V+ and 87 outputs to energize the pumps when the ECM calls for fuel pump. It only primes if it doesn’t seem crank movement (via crank position sensor)

You can jumper the pumps via terminal 87 and applying 12V+ there.

But seems like bench testing is easy enough given you have them removed. Just keep positive and ground straight. Ground is probably brown.


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[comanche344]

Ok, so thank you guys for all of the input. I ordered the parts to replace the fuel system from Nautiqueparts.com but I was completely wrong about the retro kit. That kit is only for 1995 ski nautiques. After talking to PCM directly, I was able to pull the following part numbers along with a couple of the relays.

RA080031 - Fuel Control Cell

RA080018 - Fuel Pump Supply

RA085062 - Fuel Line, Feed Fuel Pump to FCC

RA085066 - Fuel Line, TBI Return to FCC

RA085065 - Fuel Line, FCC Supply to TBI

This is for the 5.0 HO engine which is based on Chevy 305. NOT FOR GT-40.

Parts should come Friday so i'll let you guys know what happens next!

[Jimboslice54]

I just did the retro kit on my 95.

Word of advice, check that the plugs in the FCC are in the right place (use your old one for reference). The one I received, I had to change around to make sure fuel flowed right. Don't over tighten the nuts on the low pressure pump they are easy to strip.
Also, my connectors kept jiggling loose internally. After about a month I just ended up cutting them off and soldered the wires instead.

[Infinity]

I watched a video over weekend, cannot remember where I found it....but it was showing the replacement of the FCC filter and in-line filter for Nautique. The inline fuel filer was mounted under the floor, against the drivers side wall near transom. It was in fuel hose between the tank and motor of course, held on with 2 hose clamps.
Yea, lot of varnish, looks like they left ethenol fuel sitting untreated for a long time, replacement of FCC seems like he only way to go, good call. I would check inside of fuel lines too to make sure they are not deteriorated. I had a 2006 a few years ago that I replaced all the fuel hoses cause previous owner had let it sit in driveway for 2 years and they looked pretty bad.