GT-40 Troubles

Its tough to nail down problems like this since they dont happen consistently. I a$$ume you mean you replaced both the ignition and fuel pump relays. The first thing you should do is clean up the contacts where the relays plug in.

The next time you experience problems, break out a voltmeter and verify that you have good voltage to both the relays and the fuel pumps. If you do, you could have a problem with one of the pumps themselves.

You have to figure out whether your problem is electrical or fuel related. Based on your description, it could be either. Any more details would be helpful.

The low pressure fuel pump is a weak point on this engine. It regularly fails to the point where it should be considered a regular maintenance item every 300 hours or so. If you want to try a "shotgun" approach to solving the problem, replace the LP fuel pump. It's about 100.00 from Skidim, and, worst case scenario, you will have a spare pump which might save a vacation or two. Perhaps the LP fuel pump is not refilling the FCC bowl to keep up with the HP fuel pump in the FCC in some cases.

todicus, your 95 GT40 is different. That year they did not have the FCC so your fuel pump setup is not the same as 98's. I've heard of the 95's having vapor lock issues, but those result in hard starting or dying at idle rather than hesitation.

Fuel Control Cell. It is a combination high pressure fuel pump/water separator/fuel filter. It eliminates vapor lock, which is a common problem on EFI boats (you see it on carbies every once and a while, but it seems more rare) due to the higher temps in the enclosed engine compartment. This patented device really gives all PCM fuelies a huge advantage over their indmar counterparts. Nothing like trying to start your vapor locked brand-new 40k Malibu on a hot day...

98, that's awesome you've used your boat that much. For sure basic maintenance...what have you done, not done? Plugs, filters, wires, impeller, some hoses, grease steering, check strut bushing, and some others...

Sorry about your problems. Wish I had more to offer you. Keep at it with these guys and they'll get it figured out.

it's the little bushing that is in the strut (underwater gear fore of the prop). The shaft runs through it and the bushing, which is rubber on the inside) holds it in place. If you've got no vibrations or anything, I wouldn't mess with it.