05 January, 2023
I had just a few minutes with the pre-runner today to start looking into the GPS issue and to begin designing our new fuel rails. We now have all the tools and hardware we need to fabricate the rails; I just need to find the time...
A quick look at our Lowrance GPS display unit revealed that it's not seeing the "Point 1 Baja" antenna for some reason - it's not available to select in the GPS source menu. That leaves installation errors or an outright failure of the antenna to explain why it isn't "present". My first thought is that it's probably an installation error - lack of power to the "network" is my current guess. When we have time, I'll double check to see that it's properly connected to +12V when the GPS is powered on. If that's not the issue, it'll either be a cabling issue or an outright antenna failure. It did work properly "on the bench" so I'm betting it's an installation error...
03 January, 2023
Happy New Year!
We're working a few little issues on the pre-runner that need some attention: the GPS external antenna doesn't seem to be working, the oil pressure needs to be adjusted "up" a little, the rear suspension is a little "harsh" and the engine's fuel rails are incorrectly designed/machined.
The GPS antenna issue is one of a few things - no power to the "network", not connected properly, not "selected" in the navigation menu or the antenna has failed. This should be a fairly easy troubleshooting process and we hope to get it working quickly. It worked perfectly "on the bench" so I'm thinking we made an installation error...
The oil pressure is fine at the moment but we'd like about 10 psi more when the engine is hot... That's easily accomplished; the dry sump pump has a "pressure adjustment" screw that we can use to reduce the amount of oil "bypassed" within the pump. That adjustment screw has also been a persistent source of a small oil leak so we'll want to take care of that at the same time.
The rear suspension is fine over large "whoops" but is a bit harsh over "washboard" type terrain. We've not had the rear seats occupied yet so we don't know if the reduced weight on the rear suspension causes the harshness. We'll be adjusting the rear shock bypass valves over the next few outings in an attempt to optimize the ride quality under a range of loading and terrain conditions.
The fuel "rails" came with the engine core but they're not properly machined for the fuel injectors we're using. The engine previously used different fuel injectors that had provisions for seal retention so the fuel rails therefore weren't machined to provide that function. Our current injectors don't make provisions for retaining the "O-ring" seals and combined with fuel rails that also make no provision for it could lead to a major fuel leak and fire risk... Generally, the fuel rails should have a "step" machined into the injector pockets that ensures the "O-rings" are properly retained. We have new fuel rail "blanks" on order along with the tooling needed to properly machine the injector pockets for our fuel injectors. As soon as everything arrives, we'll fabricate and install new fuel rails that eliminate this issue. For now, we have a temporary solution in place - but we want a final solution as soon as possible.