Zerk fitting came out of Dexter EZ Flex - Oversized hole?

[Steve Morris]

Greasing the zerk fittings today with a Milwaukee M18 grease gun with Lock n Lube 90° adaptor. As it finished, the zerk fitting came out of the EZ Flex casting. When we tried screwing it back in, it just slid into the hole, like the hole was oversized. I'm guessing the pressure of the battery grease gun pushed it out, but there were no chips from threads peeling out. This was my first experience with a battery grease gun.

Has anyone seen this happen? What's the fix? That's going to be a PITA if I have to pull the EZ Flex out to tap oversize or replace. I'm half considering trying a press-in of the next larger metric size zerk as a Mickey Mouse repair.

Thoughts?

[FloraFauna]

This happened to me a couple of years ago.  There was no way to retap the hole without removing the axle as it was a top zirk and I was not prepared to do so.  Eventually, i got a new zirk to somewhat thread into the existing hole.  It was a real struggle, do to the limited access, and i recall i did remove both wheels. I cant recall but i might have used a metric threaded zirk of a slightly different size.  I doubt its threaded in properly but it has held in place now for a couple of years.  I am very careful when i apply grease through that one and i do not use a power grease gun on the oliver.  Not a pretty or satisfying fix but so far it has worked.

[FloraFauna]

I see our hulls were assembled in the same year.  Hmmmm.

[jd1923]

1 hour ago, Steve Morris said:

Greasing the zerk fittings today with a Milwaukee M18 grease gun with Lock n Lube 90° adaptor. As it finished, the zerk fitting came out of the EZ Flex casting. When we tried screwing it back in, it just slid into the hole, like the hole was oversized. I'm guessing the pressure of the battery grease gun pushed it out, but there were no chips from threads peeling out. This was my first experience with a battery grease gun.

Has anyone seen this happen? What's the fix? That's going to be a PITA if I have to pull the EZ Flex out to tap oversize or replace. I'm half considering trying a press-in of the next larger metric size zerk as a Mickey Mouse repair.

Thoughts?

Hey Steve, first off this is nothing to do with your new grease gun! Love a power grease gun! 😎

Zerk grease fittings when screwed in are held in place by just 2 threads. They can easily strip after greasing a few times. I had one strip just before I replaced our axles/springs last year.

Your current fittings sb 6mm (.236"). I know they are on Dexter wet bolts, so likely the same on the EZ Flex. Replace your Zerks, not with a metric size but with the SAE 1/4"x28 size.

Two methods...
1) Also get a 1/4"x28 tap to get the new threads right.
2) Just push/thread in a new 1/4" Zerk into place to form new threads, then throw out that piece and lightly thread in a new 1/4"x28 Zerk.
Choice #1 would be the correct method. Choice #2 has worked for me several times in a pinch

[Steve Morris]

15 hours ago, FloraFauna said:

Not a pretty or satisfying fix but so far it has worked.

That's what's important. I'm looking at the M8 self-tapping fitting as a slightly oversized replacement. First, I need to get under there and see if I can measure the hole using my drill index as a gauge.

Thanks for the reply!

[Steve Morris]

15 hours ago, jd1923 said:

Hey Steve, first off this is nothing to do with your new grease gun! Love a power grease gun! 😎

Zerk grease fittings when screwed in are held in place by just 2 threads. They can easily strip after greasing a few times. I had one strip just before I replaced our axles/springs last year.

Your current fittings sb 6mm (.236"). I know they are on Dexter wet bolts, so likely the same on the EZ Flex. Replace your Zerks, not with a metric size but with the SAE 1/4"x28 size.

Two methods...
1) Also get a 1/4"x28 tap to get the new threads right.
2) Just push/thread in a new 1/4" Zerk into place to form new threads, then throw out that piece and lightly thread in a new 1/4"x28 Zerk.
Choice #1 would be the correct method. Choice #2 has worked for me several times in a pinch

It wasn't my grease gun. I wanted to see how well it works. I now have a Dewalt kit on order. I'm all Makita, but either Dewalt or Milwaukee were the only quality choices. I looked at battery adaptors to use my batteries on either brand. But the Dewalt kit with case, battery, and charger was only $30 more than the bare tool. So I went that route.

My fitting is 1/4-28 SAE-LT, so the next size up is either an M7 or a self-tapping M8. I think I'll go the M8, but I need to check the hole size first, using my drill index as gauges. It was raining all day yesterday, so I put it off. Drying out and a bit warmer now.

https://www.mcmaster.com/1095K142/
https://www.mcmaster.com/8742T15/

[jd1923]

27 minutes ago, Steve Morris said:

I'm all Makita, but either Dewalt or Milwaukee were the only quality choices. I looked at battery adaptors to use my batteries on either brand. But the Dewalt kit with case, battery, and charger was only $30 more than the bare tool. So I went that route.

We're a Dewalt house which made adding the bare tool an easy addition. You will enjoy the ease of use, no more contortions to hand pump both TV and TT.

31 minutes ago, Steve Morris said:

My fitting is 1/4-28 SAE-LT, so the next size up is either an M7 or a self-tapping M8.

I would try the M7 first. 7mm converts to .276" which is 10% over 1/4" easy tap without drilling. The 8mm (.315") is a big step up requiring the correct drill size and tap. (I'm starting to love the convert function on the iPhone calculator!) 

[FloraFauna]

17 hours ago, jd1923 said:

Choice #2 has worked for me several times in a pinch

I think I probably did choice 2 as well.  Whether it was an M7 or the original 1/4-28, I can't recall.  I know I had both on hand as I struggled.

[FloraFauna]

On tricky zirks I do like the manual pump as I "feel" like I have a better feel for what is happening.  I have an electric gun as well but have found the manual trigger gun is really easier to use.  

[Steve Morris]

1 hour ago, jd1923 said:

would try the M7 first. 7mm converts to .276" which is 10% over 1/4" easy tap without drilling. The 8mm (.315") is a big step up requiring the correct drill size and tap

My M7 thread checker can start in the existing hole, but I don't want to bugger up the aluminum threads on the gauge, so I'm not forcing it. I couldn't use my drill index because there isn't enough clearance in situ. I looked for an M7 set screw to use to help start the thread, but there doesn't seem to be one. So I'm going to get a short M7 hex head screw, notch the end, and use a ratcheting box wrench to create the threads. I'm also going to go ahead and get the M8 self tapping grease fittings. They are recommended for hole sizes .299" to .303" diameter. I'm already sloppy loose on a .250" diameter. fitting, but can't get my calipers or internal micrometer in there to measure.