Di with high fuel pressure?

[Eagant5]

Anyone ever experienced high fuel pressure on a DI Engine? Just got done installing my custom feed line setup with a fuel pressure gauge inline. It’s hard to see in the vid but it’s a 120 psi gauge and it wrapping the thing around. It’s starts and runs fine. Only thing I can think of is bad fuel pressure reg or clogged return line. Also is it normal for the fuel pressure to drop after shut off when the raves cycle?

 

[etemplet]

Perhaps an injector is not sealing properly.

 

[DanSquires]

Unhook the braided hose from the compressor to the fuel rail. Crank it. If fuel comes out, it's your FPR, although they normally wont run at all with a bad regulator.

 

[mikidymac]

Fuel pressure is 107 I think so a 120 gauge is not what you want to be using as it is too close to it's maximum. It might just be maxed out and seeing every pulse. I would use at least a 300 psi max gauge.

 

[Eagant5]

Fuel pressure is 107 I think so a 120 gauge is not what you want to be using as it is too close to it's maximum. It might just be maxed out and seeing every pulse. I would use at least a 300 psi max gauge.

I was wondering the same thing. I’m gonna order a 300 psi gauge and give that a try. It starts and runs fine and ran fine last time I had it in the water. I would think that if the fuel pressure was really that high it would run extremely rich.

 

[Eagant5]

Well I installed a new 300 psi gauge and the fuel pressure is still showing high. Goes up to 140psi when putting the lanyard on and then holds steady at 135psi when running. I’m gonna pull the regulator and return line later on to see if I can figure this out.

 

[Chester]

It's the pressure regulator.

Chester

 

[Eagant5]

I changed the regulator and still same high fuel pressure issue. I ended pulling the return line off stuck it in a jug and tried it and the fuel pressure went to 27psi putting the lanyard on and went to a perfect 107psi running. I figured I had to have a clog in the return port going in to the pump canister. Pulled it out and took it apart and found this


The return orfice that sends fuel back into the canister was just about complete clogged from rusting. I had a spare pump canister from a parts ski laying around so I’m going to swap it out.

 

[Eagant5]

I got it all back together stuck the lanyard on and the fuel pump didn’t come on. Realized I forgot to plug the pump back in. No big deal right just got to plug it in. Well the fuel pump still won’t come on and now I got a maintenance light so I assume I tripped a fault code when sticking the lanyard on with the pump no plugged in. I guess I have to have the code cleared before the mpem will energize the pump again?

 

[Eagant5]

Well I broke down and bought a candoo from pwc muscle, tired of having to take it somewhere and spend $50 every time I need a maint light reset lol

 

[etemplet]

Cool, I am keeping you in mind when I begin working on the DI's I have over here. I have the CanDoo as well.

 

[Eagant5]

Cool, I am keeping you in mind when I begin working on the DI's I have over here. I have the CanDoo as well.

No problem, if you have any question just lmk I pretty much restored this one front to back including a full engine rebuild.

 

[etemplet]

No problem, if you have any question just lmk I pretty much restored this one front to back including a full engine rebuild.

I got one that needs an engine rebuild and have an engine in my war chest. I was told the compression was goot but I need to check it out and make sure it is "good to go."