Engine/Transmission (1994 - 1998) Overflow Valve?'s

[LWeight]

I was wondering where exactly the overflow valve is? I read on here if it squeaks when you pump the primer button it can be bad. Just lately my 97 started squeaking and making a funny noise when it is primed. How do you tell if its bad or not for sure? If so is there a quick fix or can I adujst it or do I have to buy a new one? I also read you can loose power if it is bad, and it doesn't really feel like its (set you back in the seat) self, well not quite as good as it used to anyway.

 

[ndurbin]

On the passenger side of the injection pump about 2-3" back from the front. I believe it is 19mm or 3/4. Has a fuel line underneath the bolt head running towards the back of the engine.



Nathan

 

[BrentL]

My overflow valve also makes a noise once it starts building pressure. I don't know that it is a concern. I would think you may need a fuel pressure gauge to detect any issues.

I spent about 3 years chasing a problem that turned out to be a bad overflow valve. I was only able to narrow it down once I installed a fuel pressure gauge.

Once the valve got warm it would release pressure from the pump.

 

[ABorchard]

Only way to know for sure if it's bad is to check the fuel pressure.

For most people it's cheaper/easier to just replace the valve.

You won't find a better price>

Precision Diesel Injection and Turbo Inc.

888-734-7349

$35 + $7 shipping and handling.





The object lower left is the oil fill cap

 

[CarlJensen]

The squeal you hear sometimes is not a problem. The overflow valve sets operating level for the inj. pump. Spring gets weak and pressure drops because the OF valve is returning more fuel to the tank and not holding pressure up where it is supposed to be. Just like all springs they will get weak from use. I keep a spare packed away. In a pinch you can pull the spring back out to . 5 inch but it is allready weak and you are better off with new. Not too expensive though.

 

[GAmes]

As an added note. The fuel line has a bracket that needs to be disconnected to get ample clearance to remove the valve. I had to remove the air horn to get to the bolt, it was installed by G. O. Rilla.

 

[ABorchard]

As an added note. The fuel line has a bracket that needs to be disconnected to get ample clearance to remove the valve. I had to remove the air horn to get to the bolt, it was installed by G. O. Rilla.

That's only on some trucks. Easy way around it is to enlarge the cutout in the manifold where it hits with a file or grinder, it doesn't take much.

 

[CEdwards]

I ordered a new one from precision diesel and it was taller than the factory part so I had to grind the top of the hex just a little bit or If i would have been thinking I could have just enlarged the opening with a good file like ABORCHARD. I too have been chasing the mystery problem around for about 6 months and it seems to be running fine after the new over flow valve. Its a very easy fix if anyone out there is having problems, only takes 5 minutes. Just adding my 2 cents in case it helps anyone else out there with the same problem.

 

[RamThatStroker]

Replaced my overflow valve about two months ago after another TDR member Rebel told me to replace it because of an intermittent miss and blue smoke that I had been chasing for a couple of months. Filed the manifold like suggested above and removed and replaced. . piece of cake. After replacing the valve, my trucks idle changed, quieted down, and the miss is gone finally

 

[CarlJensen]

Amazing what a half inch piece of spring can do to you huh!!

 

[RamThatStroker]

Amazing what a half inch piece of spring can do to you huh!!

You got that right. Heck I was ready to trade in my truck for flowersmoke :-laf j/k.

 

[LWeight]

Well thanks for all your help guys i'll have to get a new one in and see what it does.

 

[surfbeetle]

Where to get the part from?

I am using TST #5, can I get the overflow return valve from Cummins or is there a better aftermarket part?

 

[CEdwards]

Read Reply #4

 

[Dave M]

I am using TST #5, can I get the overflow return valve from Cummins or is there a better aftermarket part?

I got mine from Piers Diesel:



www.piersdiesel.com



Cost was a little more than that other price mentioned but Piers gives good troubleshooting advice when needed. Worth the extra IMHO.



Dave

 

[Dave M]

Fuel Overflow Valve Info:

Thought you might like to see this site for pics and description of the fuel overflow valve:



The site that covers the fuel overflow valve replacement is www.dodgeram.org . Here is the link to that info:



Fuel Overflow Valve:



http://www.dodgeram.org/tech/dsl/troubleshooting/injector_pump.htm#Overflow



Dave

 

[HEMI®Dart]

I just replaced my overflow valve with one I got from Marty. The new one will hold pressure for about 10 mins after engine is shut down before it drops to 0. Is this OK?



I noticed with the new valve the needle bounces all over the place. Old one didn't do it. I am using TST's snubber. Tough to get a reading at idle. I think it's around 20-25 psi @ idle. Old one was 17 psi.



The old OFV was the 2 piece model. I took it apart. Spring measured . 450. Shims were . 075.



Also What are your guy's opinion on my pressure gauge? It's a Summit liquid filled 1. 5" 0-35 psi mounted to TST's snubber, in the air bleed hole on top of the filter head. Is TST's adapter going to hold up, or will it break?