3126 Priming Pump

Wish I would have seen those Loxx snaps sooner. Didn’t know about them.
Canvass guys get crazy busy now, but I might look in to switching some of mine out too.
The current ones let loose in spots in heavy winds. Mostly on the two sides about where the steps up to the gunwales are.
 
JVM225 said:
Wish I would have seen those Loxx snaps sooner. Didn’t know about them.
Canvass guys get crazy busy now, but I might look in to switching some of mine out too.
The current ones let loose in spots in heavy winds. Mostly on the two sides about where the steps up to the gunwales are.
Click to expand...
JVM - Sailrite.com has them...
 
JVM225 said:
Wish I would have seen those Loxx snaps sooner. Didn’t know about them.
Canvass guys get crazy busy now, but I might look in to switching some of mine out too.
The current ones let loose in spots in heavy winds. Mostly on the two sides about where the steps up to the gunwales are.
Click to expand...

same here. I'll report back on how the work..

20200416_152103.jpg
20200416_152110.jpg
 
JVM225 said:
I know that if I had about 3 shock cords on each side it would solve the problem for sure, those are the only areas that let loose, but I’ve been reluctant to do that because I don’t like the way they look.
Click to expand...

Update

These snaps have been very solid. I'm happy I replaced them, and my gelcoat will thank me.
 
Where we stayed on topic...great thread! So thankful for this forum.
My pumps squirt diesel all over and need to be replaced so I can replace the secondary filters.
Are the o rings needed and if so where do they go?
 
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Njlarry said:
Where we stayed on topic...great thread! So thankful for this forum.
My pumps squirt diesel all over and need to be replaced so I can replace the secondary filters.
Are the o rings needed and if so where do they go?
Click to expand...
Those of us with priming pumps that use them (some don't) have replaced them. From what I understand you are not able to rebuild them, but for under a $100 it's not a big deal every 10 years
 
Picked up two today at Foley Cat of NJ. 71 bucks apiece plus 5 each for the two o rings. Tried
to use Hoovers as much closer but they didn't sound too friendly over the phone especially if you don't " have an account".
Foley was very helpful. Showed me how the cooper washer goes on first and the o rings go around outside of them. Need to pick up 1 inch open end wrench.
Hope to at least get the starboard engine and secondary filter done this weekend before attempting wotking blind on the port side.
 
Take a picture of how the orings are supposed to be installed.

I only installed the copper washer. Everything works, but may need to revisit.
 
dtfeld said:
Take a picture of how the orings are supposed to be installed.

I only installed the copper washer. Everything works, but may need to revisit.
Click to expand...
I'm old and now covid positive but as I recall there's just the copper crush washer involved...
 
Dave, at Foley they gave me a CAT drawling which I searched for all day with no luck. Will post it when it surfaces. The o ring sets against lip that is concentric to washer so that the o ring goes around washer.
The CAT operation manual just says to pump till resistance is felt. How much restance? No mention of opening bleed screw or listening to fuel returning to tank.
 
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Njlarry said:
Dave, at Foley they gave me a CAT drawling which I searched for all day with no luck. Will post it when it surfaces. The o ring sets against lip that is concentric to washer so that the o ring goes around washer.
The CAT operation manual just says to pump till resistance is felt. How much restance? No mention of opening bleed screw or listening to fuel returning to tank.
Click to expand...
I have the drawing, but when I removed the existing pumps, there was no oring, only the copper crush washer. My thinking is the oring may be necessary for some other model, or configuration. But not on the marine 3126.
 
That could be. Will let you know how my old ones were done.
Did you just pump till resistance felt or open a bleed screw somewhere or listen to fuel tank return?
 
There is a small knowb on the underside of the pump assembly you need to turn till the pointer in inline with the pump to prime and turn 90 to seal it off for running.

There is not a great way in my opinion on feeling resistance to tell if all air is out.. I usually give it a couple minutes of pumping and see if she will will start. If not needs another 50-100 pumps. If you are quiet you can hear fuel flowing back to the tank.

Frank's method is to open throttle half way and crank till she fires, and quickly return to idle. I usually use a combination of both.

You'll know it's completely primed when it smooths out at idle

If she isn't completely smooth or you have power issues, recheck the primer knob is set (I've forgotten on occasion).
 
You can continue pumping the priming pump until there is solid resistance and you can no longer feel fuel moving. The systewm allows you to force fuel into the return system until there is no air left in the filter or lines. Feeling the right point is pretty subtle and it difficult to identify.

The other issue for me witrh priming and leaks was that the knureled knobs on the ball valve will eventually fail to grip the stem in the ball valve and you cannot tell when the valve is closed. You find that out when you get diesel fuel all over your bilge as it will leak out of the priming pump.

I eventually gave up trying to "divine" when that damned ball valve was closed and started priming the system the old fashioned way by filling the filters by hand.
 
Finally got to replace both priming pumps this weekend. As you can see from the attached photo the o rings do not seal against anything on my 3126s. I only put it on because I had it and it made me "CAT Official". The o ring for the port engine ran away somewhere so it didn't get one. Neither leaks so other than an extra ten bucks for CAT can't see that they do anything. There were no o rings on the old pumps.
Hope to change the filters this weekend. Plan is to plug filter center hole, fill outer holes, attach and hopefully not have to use the pumps for the whole filling. When I tried using them I could not hear any fuel returning to the tank so will use the bleed bolt.

20210912_125529.jpg
 
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