shimming the FPR

[dieseldork]

I've read the wiki thread but am unclear of the shim placement. Do they go in the brass sleeve under the spring or at the cap? Please help im in the middle of it now.....

 

[roosterdiesel]

What are you using as a shim?


I used a machined shim and put it in the cap. A small cap head screw ground down to get the desire pressure would work in the same way with the threaded part inside the spring. A small dab of grease to help hold it in wouldn't hurt.

Washers can also be used, some people have found some small enough to go in the brass and then put the spring in. I would think it would be tough to keep washers in the cap.

Basically whatever shim you use needs to contact the spring on either side.

 

[whatabudro]

I've read the wiki thread but am unclear of the shim placement. Do they go in the brass sleeve under the spring or at the cap? Please help im in the middle of it now.....

Into the brass sleeve, then the spring goes in.

 

[dieseldork]

Thanks guys, I used #4 stainless washers in the sleeve between the spring and the brass sleeve, The washers had to be filed to let slide into the sleeve. I ended up using three washers and ended up with 70 psi straight up. Truck idles noticably smoother, I have yet to take it for a drive, Will be shortly. Vey happy with the results and look forward to doing some more soon. Oh ya an FYI there are several different size #4 washers out there, Try and find the smallest ones you can if your gonna do this mod.

 

[CHPMustang]

3 washers is the usual recipe I get for 70-72 psi

 

[hammer450r]

is there a write up on this somewere?

 

[whatabudro]

All our writeups are at the top of this page. Click on Technical Articles WIKI