High speed check valves with mechanical pump

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getblown5.9

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When using a waterman setup, haisley sells the high speed check valve pair, a 50psi and 70psi piece.

I am using a DSR pump that does not have a return built in like the waterman. Fuel goes in, and fuel goes out the pressure side, only thing controlling pressure would be RPM or some type of regulator. I got to thinking about how this all works and I am now confused at how/where the high speed check valves would be used, or if I just need an external fuel pressure regulator with one of the check valves on the return from the injection pump.
 
You can put the check valve before the pump with no pump return. Or you can put check valve on the return line.
 
Can you run with no pump return? Isn't the fuel used for cooling? Its short runs but still seems like a bad idea.
 
There are alot of tractors with no return. Just put the check valve on the return either setup works. The thing im not sure about is some run the return and 3way dump back to the inlet side of fuel pump and not to tank so like a loop line. Seems you may cause more air to get into the system maybe not.
 
Per Scheids specs it goes before the injection pump to control overall pressure then just use either a regulator or standard Bosch overflow valve out of the injection pump. I have the DSR also. I called them directly and upgraded to the -10 pump fittings. Real nice guys to talk to and help you out with questions. I don't have any pics on my phone but I can get you some tonight maybe.
 
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yea i am going to get the -10 pump fittings, its just an o-ring fitting.

I dont get how a check valve in the supply line before the injection pump controls the pressure properly
 
I think that check valve is only in there to hold the pressure after the motor is stoped. So it would have to go before the pump. The regulator or ofv on the pump would determine the running pressure.
 
I guess when the pressure reaches 70 psi at the injection pump it opens the high speed valve and dumps the excess back to the cell. I don't know how much pressure it would build without it inline.

The pump fittings were 12$ each from DSR. Going with -10 lines makes adapting down to -6 kinda pain In the ass. I built all my lines out of stainless braided hose. Push locks would be easier. If you do stainless lines get the tools from the get go and save yourself some cussin. Lol
 
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That has to be just a higher flowing check valve, I can't see not running a regulator.
 
After some more reading, heres how I think it should work.

The 50psi replaces the OFV on the outlet of the p-pump. This ensures there is always 50psi in the pump housing, and if there is more it opens the check valve to return flow back to the fuel cell.

The 70psi needs to be installed on a tee between the lift pump and injection pump that returns back to the cell. If at higher rpm the DSR is making more than 70psi, the check valve will open to keep pressure at 70psi. This is now the regulator.

This way would make sure there is always 50-70psi in the injection pump case.
 
That is correct. With the lower pressure poppet on the return side of the pump there will always be fuel flowing through the pump.
 
Maybe I'm wrong but the way we have ours setup and the way we were told to setup is the brass poppet/ check valve is on return side of the injection pump. Running a DSR pump with a 3/4 supply line into our injection pump. Check valve regulates fuel pressure. Simple setup no regulator needed. As pump pressure and flow goes up check valve allows more fuel through it. We see 60 psi fuel pressure wide open about 65 at idle. Works great and simple just my .02 though
 
dieselpolaris said:
Maybe I'm wrong but the way we have ours setup and the way we were told to setup is the brass poppet/ check valve is on return side of the injection pump. Running a DSR pump with a 3/4 supply line into our injection pump. Check valve regulates fuel pressure. Simple setup no regulator needed. As pump pressure and flow goes up check valve allows more fuel through it. We see 60 psi fuel pressure wide open about 65 at idle. Works great and simple just my .02 though
Click to expand...

That would work fine as long as you have enough return flow to keep pressure down.

from phone
 
dieselpolaris said:
Maybe I'm wrong but the way we have ours setup and the way we were told to setup is the brass poppet/ check valve is on return side of the injection pump. Running a DSR pump with a 3/4 supply line into our injection pump. Check valve regulates fuel pressure. Simple setup no regulator needed. As pump pressure and flow goes up check valve allows more fuel through it. We see 60 psi fuel pressure wide open about 65 at idle. Works great and simple just my .02 though
Click to expand...

So I only need one check valve to run it like this?
 
getblown5.9 said:
So I only need one check valve to run it like this?
Click to expand...

I Would just use a good quality regulator after the injection pump. And use at least 6an for return line right out of the injection pump. What is this pump rated for gph?

from phone
 
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