Stanadyne FM100 fuel management system upgrade

Project finished.

It took about 45 minutes to get the old filter mess off the firewall, get the new one mounted, screw in all the fittings, and connect it all back up. Then it took another hour and a half to fix all the leaks. (I figured one wrap of pipe tape would be enough, and snug would be tight enough, but I was wrong on both counts. I had to take it all apart and re-tape and put some smoke on them to stop the leaks.)

Anyway, the two inch spacers worked perfectly, and I had all the bolts and washers in my re-use collection so I didn't need to drop everything and go to the hardware store. You can see in the picture I used a washer on each side of the filter head, and another at the firewall. I also used a lock washer as well. I decided to put the pressure gauge on the input side and maybe later if I get motivated I'll add another to the output side so I can see pressure loss across the filter. Or not.

Once it was all ready, I connected the vacuum pump to the petcock and opened it up- pulling fuel through the filter to fill it. (LAST TWO PICTURES) The only air was a small bubble in the output line from when it was disconnected. The truck surged a couple times then settled itself.

Right now I have the truck parked a little nose up in the driveway, so I can see if the leaky box filter was the cause of the hard starting. I'm still not sure I want to spend the money for the heater yet, or just leave it as is.

standyne fm crap

here is some more info on the FM stuff

Mainsail said:

Right now I have the truck parked a little nose up in the driveway, so I can see if the leaky box filter was the cause of the hard starting.

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I left the truck out all night nose-high in the driveway. Previously this would have cause the truck to start, then stall, then be very hard to get restarted. I went out this morning and it fired right up and never even hiccuped.

I'm glad that's solved. It wasn't a problem if it was parked level or nose-down, but it can be hard to find a spot like that all the time.

Glad it worked to cure your issues. Nice install too. If anyone is worried about the "water in fuel" issue, they make a clear bowl that will screw on to the bottom of these filters so you can see AND drain it from the system. The stock filters only warn you, they don't block the water.

Mainsail said:

I've got most of the parts gathered for my install. I have some spacers to move the filter head off the firewall, but they're two inches long so I may need to find something shorter. I plan to connect the vacuum pump to the petcock on the extra output boss and pull fuel up through (if it can be pulled through the mechanical fuel pump).

View attachment 455367View attachment 455368

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what size fittings did you use? Thread size?

av8rnik said:

what size fittings did you use? Thread size?

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Wow, I really don't remember any more. I took the filter head with me to home depot and test fit each fitting before I went to the register.

That is what I was planning on doing...hopefully only have to make one trip. Where did you get thread sealant that is compatible with diesel?

I used teflon tape, although I have since heard a reasonable argument against using it- stray bits can get into the IP and make life miserable. I'm not sure why the stuff in the can is better; couldn't it also get into the IP? Anyway, mine is still together and working great, and this thread reminds me I need to crack the valve on the bottom of the filter in case there's some water in there.

Bump for Case.

gimpyrobb said:

... they make a clear bowl that will screw on to the bottom of these filters..
.

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I just gave Recovry4x4 two of the glass bowls that had been riding in my truck forever. Our newer John Deere engines run them.

Skinny what is the part number on the filter head, I was on stanadyne page and saw several fm 100 heads with different part numbers.

Mainsail said:

I used teflon tape, although I have since heard a reasonable argument against using it- stray bits can get into the IP and make life miserable. I'm not sure why the stuff in the can is better; couldn't it also get into the IP?

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I think the liquid stuff would dissolve. The tape just breaks up into particles.

Just a guess.

If the liquid stuff dissolve it would not seal would it?
The paste type works well if you do not over use it.
Same as the tape, if you do not over wrap it and wrap it correctly you are fine. How tape got a bad wrap is FNG's who have no clue on what direction and how much to wrap. Teflon is NOT fuel rated. You need to use fuel/gas rated tape. Most of the time it is yellow in color.
When wrapping you want to wrap it so when it is installed it is not unwrapped. Typical is to hold the fitting in your left hand with the threaded end facing your right. Wrap the tape bottom to top (clockwise) so when the fitting is installed you are not unwrapping the tape as it is tightened.

The head I got was 3/8" NPT fittings. I do not have the part number but you can get them at any Stanadyne dealer, Napa sells a generic version (same exact head/filters/accessories), or from dieselstore.com like I did.

Here is a great .pdf breakdown of the FM series filters.
www.btlrus.com/99920B.pdf

I also used the longest filter that would fit, 6" length. I put 90 degree fittings to keep it tidy as well. Read page 1 of this post very carefully. I posted dimensions for all the fittings and lines that you will need. I used the fuel sealing paste since Westech has it spot on. White Teflon is not fuel rated. It also can break up and end up in the IP. Not a problem for all the fittings because it will be filtered out. Except for the last one that goes into the IP, any contamination there goes into the IP.

The liquid has been on there for over two years and tighter than a ducks...

I also installed a secondary FM100 filter:
http://www.steelsoldiers.com/showth...ne-FM100-Primary-and-Secondary-filter-install

Merry Christmas Cuck Vee'rs!!!

It seems my ad has expired, but i still have one or two FM100 kits available. The base and 6 filters included.

Thanks for the clear bowls Phil. I was able to completely disassemble them for cleaning. Very nice.