• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Added Racor prefilter/not priming

R

Rodd

Recruit
Messages
1,731
Reaction score
1,042
Location
Antelope, CA
I just added a new racor 10 micron prefilter. The filter is an R90T. The head is a 690 I believe because it doesn't have a primer. I cut the stock fuel line back by the rear diff and connected the fuel line to each end. I filled up the filter w/ fuel and I can't get it to prime. I even replaced the old pump w/ a new pump. Any suggestions?

Thanks
 
I also dropped the tank and took off the filter sock. The pump is pulling from the fuel in the filter and it starts but it won't stay running. Is the stock pump not strong enough to pull through the filter?
 
Have you tested the stock pump with a gauge, it may have been on it's way out and added restriction of the Racor is not letting it pump, also double check that you have not induced an air leak, my stock lift was able to pull fuel through a Racor, Heath h/o pulls it better and walbro pulls best of the 3.

Actually my IP once the filter is primed, will pull it's own fuel through the racor, so now I'm leaning to an air leak or that you still have a lot of air in the IP/nozzles after the 1st attempts that needs to be vented out via running it.
 
The pump is brand new. I jumped it and ran it for 10 minutes and it keeps spitting mostly air through the filter bleeder w/ a little fuel mixed in. I cut about a 6 inch section of the sock metal fuel line and flared the ends and connected 3/8 fuel hose w/ clamps. That is the only place air can enter into the system. What is the best way to see if air is getting in there?
 
If it is spitting air through the bleed then it is getting air, I suspect your racor still has a lot of air in it, I'd pull the inlet to the IP and run the lift until I got solid fuel stream from it
 
How can the filter have a lot of air? I filled it to the very top twice. I was thinking of putting the old pump before the filter and trying to push and pull at the same time.
 
put a little air pressure into tank and you will probably see fuel drip at new filter or fittings by it.
 
Last edited:
bison said:
Air can leak in trough the bowel 0 ring if it aint seated right.
Click to expand...

x2.

My first run in -10F temps last winter uncovered mine wasn't screwed together quite tightly enough to seal against trying to pull v cold fuel w/ its higher viscosity. Experienced a notable amount of fishbiting, that became less often as the drive time warmed the truck & slowly warmed the fuel via recirculation.

Soon as I was home in a warm shop, I checked the system & found it just needed to be tightened a bit. Next cold start/run at below 0 temps showed no more symptoms.
 
Having slept on it (not literally), I realized that the bowel O ring is in the center hole of the filter and the filter housing has the male portion that goes into it. This is the only O Ring. There is no outer O ring like on an oil filter that mates up to the top of the housing. Is it supposed to have one?
 
Rodd said:
Having slept on it (not literally), I realized that the bowel O ring is in the center hole of the filter and the filter housing has the male portion that goes into it. This is the only O Ring. There is no outer O ring like on an oil filter that mates up to the top of the housing. Is it supposed to have one?
Click to expand...
There's got to be something missing some where.its quite possible to have an 0 ring missing from the get go.Does that filter has tread on the out or inside where it meets the housing.
Look for a groove on either one that could hold a 0 ring.
 
There is an O ring on the inside just below the center hole threads. There is a groove on the outer edge of the cylinder where you would normally see an o ring on a typical fuel filter. I am headed to the only racor supplier in Sacramento to see what they have.
 
I'm an idiot. I saw the o ring/gasket that goes between the housing and the filter sitting where I have had the filter/housing sitting for the last year waiting to be installed.
 
You must log in or register to reply here.
Back
Top