HELP! Priming Cat 3116

Discussion in 'General Discussion' started by srt8mag, Feb 20, 2011.

  1. srt8mag

    srt8mag New Member

    146
    Jan 2, 2008
    Mt. Pleasant, SC
    280 Sundancer SOLD
    4.3's w/ A1's
    Need some quick tips and advice on priming a 3116. Algae clogged Racor and shut down port motor. Cleaned Racor and changed filters but can't get primed.
     
  2. jitts3

    jitts3 New Member

    Dec 16, 2008
    Monroe Twp. NJ & Fon Du Lac, WI
    1973 SRV 240 and 1978 SRV 200
    73" 307 CID Chevy OMC Stringer, electric shift. 78" 350 Mercruiser
    Ok. I have no experience in marine diesels, however I own 2 Peterbilts, both with Caterpillars. I did look online and found out that the Raycor you speak of is a fuel/water seperator. Priming a Cat is easy.

    First spin off your fuel filters. I'm gonna assume you have 1 primary filter. You could have a secondary. Fill them to the top with fresh diesel. Reinstall them.

    Just above the primary filter (should be on the block) should be a small knob. It is about the size of a 50 cent piece. Turn it counter clockwise. Once loose pull it out. It will come out 2-3 inches. That is your hand pump to prime the engine. Punp it till solid. Could take some time depending on how much air is in the system. Once solid force it down and turn it clockwise to lock it again.
    Start her up and keep an eye on the fuel press. If it will high idle for 5 minutes at 1000 rmp you have it made in the shade.

    I'm gonna pm you my cell number. I can text you pics of mine or talk you thru if you need.
    Steve
     
  3. fwebster

    fwebster Well-Known Member TECHNICAL Contributor PLATINUM Sponsor

    Oct 6, 2006
    Middle Tennessee ; Panama City Beach, FL
    1996 450DA
    3116 Caterpillars
    If the dirty Racor shut down the engine, then the secondary filter is full of air and needs to be purges as well.

    The priming pump must first be put on line by rotating the small knurled ball valve at the inlet to the priming pump 90 degrees marine engines.

    The Racor filter body must also be filled to the top before you can prime the secondary filter.

    Finally, what you have growing in one tank is also in the other.....don't take the boat out again until you have changed both the Racors and secondary filters on both engines.
     
    The Bill Collector likes this.
  4. Odyssey

    Odyssey Active Member

    Jan 8, 2007
    Delray Beach Florida
    44EB
    CAT 3116
    Ditto on what Frank said. One other note - I am told that some 3116's have a priming mechanism (is that correct Frank?). Mine do not. When I change my filters, it always takes a while to get the motors started. I just have to sit there and turn them over and over until they finally fire up. Another thing that I would like to have Frank comment on - I was told never to fill the spin on filters with fuel because that fuel has not been filtered.

    Randy
     
  5. fwebster

    fwebster Well-Known Member TECHNICAL Contributor PLATINUM Sponsor

    Oct 6, 2006
    Middle Tennessee ; Panama City Beach, FL
    1996 450DA
    3116 Caterpillars
    Randy,

    Caterpillar's position is that you should install the secondary filter dry and use the engine mounted priming pump to fill it and purge the air.

    The problem with this is that the priming pump is fed fuel thru a little ball valve. Open the ball valve when you need it; close it when you are done. The priming pump doesn't have much of a seal and will leak fuel everywhere if you leave the ball valve open. The ball valve has a plastic knob pressed on its stem and that know will rotate on the valve stem so you don't know if it is open or closed. For that reason, I fill my secondary filter to overflowing with clean fuel from a filtered source before installing them. From there, you just crack the throttles and fire the engines up.......they will immediately fire up, might idle rough, but will purge themselves in a few seconds. It isn't what Cat recommends, but it sure saves a lot of wear and tear on the starter and ring gear.

    Also, you cannot purge the Racors with the Cat priming pump. They must be filled by hand.
     
  6. Odyssey

    Odyssey Active Member

    Jan 8, 2007
    Delray Beach Florida
    44EB
    CAT 3116
    It's interesting that this thread was just written. On Friday, I went to look at a 44 EB with a friend of mine and one racor on each engine had dark brown sediment in the bottom half of the jar. The other racor was clean. Both racors on both engines were valved in the on position. He started up the engines fine, I guess because of the clean racor.

    I should have taken a picture.
     
  7. HUMPH

    HUMPH Well-Known Member

    Nov 4, 2009
    SF BAY AREA
    2003 410DA,
    2004 C14 Caribe
    CAT 3126TA's 350HP/
    50HP Honda
    Frank, is there a diesel fuel additive you can recommend? I thought I saw it on a thread some time ago but without having diesels at the time I didn't pay too much attention.
     
  8. fwebster

    fwebster Well-Known Member TECHNICAL Contributor PLATINUM Sponsor

    Oct 6, 2006
    Middle Tennessee ; Panama City Beach, FL
    1996 450DA
    3116 Caterpillars
    Ken,

    I've written it up as a FAQ and have it here. I'll either post it or send it via PM when I get to it.
     
  9. quality time

    quality time Well-Known Member

    Oct 30, 2007
    Upper Chesapeake Bay
    2003 480DB and Kencraft 190 CC
    QSM11's
    Frank,
    Can the priming pumps be rebuilt? Mine leak fuel really bad while pumping and I had a hard time getting them to prime last time. I assume there's an o-ring that's shot?
     
  10. katricol

    katricol Active Member SILVER Sponsor

    Mar 4, 2008
    LONG ISLAND SOUND
    2000 540DA
    CAT 3196 660 HP
    Frank...I'd like that diesel additive answer also. (I have horrible luck with this site's search feature). Also I thought it was bad to keep turning over the engines for a long time as Randy does, because the exhaust can fill-up with water. Or is that only a problem with the genset?
     
  11. ImpulseIII

    ImpulseIII Active Member

    Oct 3, 2006
    Jersey Shore/Venice FL
    2001 410 Sundancer
    Caterpillar 3126TA
    Aaron, ask your question at the other place.....
     
  12. quality time

    quality time Well-Known Member

    Oct 30, 2007
    Upper Chesapeake Bay
    2003 480DB and Kencraft 190 CC
    QSM11's
  13. Odyssey

    Odyssey Active Member

    Jan 8, 2007
    Delray Beach Florida
    44EB
    CAT 3116
    I'm glad to hear that Frank fills up his spin on filters. I'll be doing that from now on.
     
  14. fwebster

    fwebster Well-Known Member TECHNICAL Contributor PLATINUM Sponsor

    Oct 6, 2006
    Middle Tennessee ; Panama City Beach, FL
    1996 450DA
    3116 Caterpillars
    Aaron-
    Yes, they can. However, that most likely isn't your problem. The ball valve on the one that leaks is open which keeps the priming pump online all the time. Since there is no stem seal on that pump, anything that gets by the piston/o-ring just runs by the rod hole in the cap and makes a mess under the engine.

    All that pump does is to fill the secondary filter and push fuel thru the fuel chamber in the head and on into the return system. Replacing the o-ring or seal will help,and in the meantime, shut the ball valve and fill the filter by hand with clean filtered fuel.

    HUMP_
    Your PM mail box is full.....I can't send you anything. I have submitted the additive piece to CSR for use as an article on the opening page, so watch for your answer there.

    Ric-
    Its on the way via email........don't duplicate or pass on to anyone else, please.
     
  15. ImpulseIII

    ImpulseIII Active Member

    Oct 3, 2006
    Jersey Shore/Venice FL
    2001 410 Sundancer
    Caterpillar 3126TA
  16. Warren

    Warren Guest

    Aaron, there is certainly nothing wrong with Frank's advice in filling the filter before installation - I do that also then I use the prime pump. I did have a priming hand pump that did not work as the seal(s) were shot so I replaced it with a new Cat hand pump #110-4397. Less than $50 as I recall and no more leaks when I pump it.
    W.
     
  17. fwebster

    fwebster Well-Known Member TECHNICAL Contributor PLATINUM Sponsor

    Oct 6, 2006
    Middle Tennessee ; Panama City Beach, FL
    1996 450DA
    3116 Caterpillars
    Jim agreed to post the piece on fuel system management and additives as an article on the opening CSR page. You can get the additives info there.
     
  18. Cocktail Time

    Cocktail Time Active Member SILVER Sponsor

    580
    Jul 9, 2007
    Lake Lanier, GA
    1998 400 Sundancer, Garmin 840xs GPS, Furuno RDP-110, B&G GPS pilot etc.
    Cat 3116's, Westerbeke 7.6kw
    I have a slight leak in one of my priming pumps. Does anyone have the part number for the rebuild kit? When I search 3116 priming pump kit I get all kinds of different parts none look right. Thank you! Great post here.
     
  19. endless seas

    endless seas Member

    971
    Feb 13, 2008
    Baltimore,Maryland
    1997 450 DA
    Cat 420
    When filling my Racors because of the reach and mess from spills I found out using the kerosene pump with D batteries from Lowes was a fantastic find. The pump fit right in the opening of a two gallon can (no-spill ) and the extension would reach my application perfectly to the top of the open Racor. All you did was toggle the switch on the pump from on to off until the razor and filter were filled. Put the lid with new o-rings on and your done. Saved my back for over 8 years.
    Not a sermon.....just an idea.
    Also forgot to mention after buying new pumps from Cat I siliconed the knobs so they wouldn't vibrate open and never used them again just filled the spin ons.
     
    Last edited: Feb 23, 2018
  20. peterkvs

    peterkvs Member GOLD Sponsor

    500
    Nov 11, 2012
    Guntersville, Alabama
    400 Sundancer 1999
    3116 Cats, 1000 hours
    I suffered with leaky priming pumps for a year. I finally bought two new ones from Cat after farting around with them just made things worse. They are a suck design. Now I no longer use them. If you profile the filters when you install them you will never need the pump, unless you run out of fuel! Just be sure to pour the fuel into the filter in the ring out outer holes. This will insure that the fuel is filtered before it gets to the injectors. I have a rubber plug that I keep in my tool bag that fit the center hole and makes this easier.

    Pete
     
    Cocktail Time likes this.

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