GT-40 will not start after changing fuel filter

Ran the boat all over the lake today. Weehii!

My 1998 Air Nautique got sunk by a friend when it had 2,000 hours on it. Never once did it fail to start.

My 1999 Pro Air Nautique, bought with 900 hours on it and 500 more put on it, got burned up accidentally by my (not kidding) great (and I mean really good people) neighbors who were burning leaves next door and didn't get the fire put out completely.

Bought a 1998 Sport Nautique recently with 242 hours on it. This is the only one so far that would not start....ever....in all the years and hours I've put on these boats. Yea, that's pretty reliable I'd say. All the same engines; love these engines.

Gosh Pete you can find the relays for around 5 bucks if you don't snag them like Ken. What does it cost to build a suppression circuit? Charles's relays lasted 20 years, Mine were 22 and were only changed because the plastic cracked that held the metal bracket to them so they didn't stay mounted on the plate.

8122pbrainard wrote: The failure rate of the relays seems pretty high due to reports here plus the fact that some even carry spares. Yes, they are a common relays used for many applications in automotive but the application on a inductive load causes arcing of the contacts that drastically reduce the life especially on a DC inductive load. When designed, someone missed the fact that arc suppression is needed. It's a simple RC circuit that's simple to add. Commercial snubber modules are even available. Snubber modules

So a 20 to 25 year lifespan on these things is unreliable ?

Let's look at automotive uses like on say a 93 Grand Cherokee with 250,000 plus miles and it's relays are original. The fuel pump relay and the A/C compressor relay are the same as these gt-40 relays without the bracket. Now what kind of loads are those?

Maybe you'd rather get towed in or paddle in if you were broken down instead of having a couple of spares that take up roughly 2 cubic inches of space and can be changed in a few minutes.

You need to go back to picking on electronic modules and filing your points

The bosch type used on your boat are pretty good but failures can happen.   You can do lots of cool and simple circuits using them, here is a control panel for a diesel generator the I designed and built, works pretty good.

Alan,
        McMaster used to have the mercury relays but checking it looks like they too discontinued them. The replacement you got, was it a mechanical relay or was it a solid state? In the past 20 years, solid states have become very popular for resistance heating for on/off as well as chopping the wave form for variable heating. If the replacement was mechanical, look into the solid state or a RC to protect the mechanicals contacts.

Rakerdeal

I don't know what you bought for relays but if you walked into the auto parts store and said give me a couple of relays like this,you should look at the little schematic on the side and make sure it matches the original schematic.

The originals have a resistor in parallel with the coil between the 85 and 86 contacts and hopefully your new ones do too.

Here's what the schematic should look like. That blank rectangle on the left is the resistor

If there is nothing going around the coil, you should get relays with the resistor for suppression of voltage surges

If in doubt, if you get the PCM relays you can't go wrong

The link below is good info

link about relays

When I get back north I will check and see what numbers are on my old and new relays. Mark had in the past listed their part numbers but I cannot find it. The numbers on the new did not match the old but they had the correct "water resistant" plug and mounting lug that the ones that come from a Jeep don't. With Pete talking snow I'm in no hurry

rakerdeal wrote: Keno I'll see what I got tomorrow. You guys are surely having fun now interacting well above my electronic/mechanical performance or play level. Still I do enjoy reading and learning a little.

Just trying to make sure your fix is good and doesn't lead to any other problems.

Your search skills are better than mine Ken That's them and they do work (so far)

Here's the info on a Hella 87411 which supersedes the 87412 mentioned in Lewy's post and cross references to the 4RD 960388-31. and the 007794301. It's in the link at the end of this post

8122pbrainard wrote: Yes, they are a common relays used for many applications in automotive but the application on a inductive load causes arcing of the contacts that drastically reduce the life especially on a DC inductive load. When designed, someone missed the fact that arc suppression is needed.

Cheap Chinese made piece of crap is only good for 100,000 cycles when used on an inductive load .

German company with BIG factory in China

Hella relay

Keno my schematic is different so I need to get different ones. Any of those posted that you recommend?

Keno, ordered the ones you posted from Napa/Echlin AR174.

rakerdeal wrote: Keno my schematic is different

rakerdeal wrote: Here is my current shcmatic:

They are the same. You need to look at the terminal numbers.

Hey guys I am now having a similar problem to the one described at the start of the thread so I thought i'd get it out there for your thoughts.

I recently disassembled and resealed/ reassembled the line between the low pressure and high pressure pump on my 95 GT-40 in order to correct a fuel leak. When I tried to start the boat, I got a second of the engine firing and that was it. I can hear the low pressure pump running, and I also cycled the ignition several times to see if I could get more fuel in there. Eventually, the battery died.

Thanks in advance for your help.

Mike

It consistently fires for about a second

And confirmed the lanyard is attached

I will look at the breakers