Grease Fittings

[Captain Ned]

I'd like to have a word (or 42) with whatever accountant decided that press-fit grease fittings would save a few pennies over tapped/threaded fittings. In lubing up my GT2544's deck, two of the bleeping things have come out with the grease gun. Oh well, this will be the 3rd trip to the dealer for this round of PM.

Trip 1: Buy PTO/deck belt & air filter
Trip 2: Return air filter because it's the wrong one even though my slip has the right part #
Trip 3 (so far): Buy cheap grease fittings that are unobtainium in local car parts stores because cars all use threaded/tapped fittings.

 

[Willl]

Thread Forming Grease Fittings, Thread Forming Zerk Fittings, Spin Drive Grease Fittings

 

[Captain Ned]

Too bad the Cub fittings are 3/16".

 

[highboy1975]

my dealer said to put a punch in the opening and give it a few taps to form a lip at the contact point. i havent had any problems yet with grease fittings yet on my 12 yr old 3185. im assuming theyve all been replaced at this point.

 

[Captain Ned]

To my mind using self-tapping fittings will introduce metal shavings into the bearing. If not, I'd certainly like to avoid the alternative, which would be disassembling every bearing with a fitting, tapping it, cleaning it, and repacking it.

 

[beenthere]

That must be MTD that is doing that. Maybe send them a note.

 

[Bird]

I used to keep an assortment of SAE and metric grease zerks, all threaded of course. But when I lost a pressed in fitting, I'd take one of the threaded ones, and grind the threads down a bit on my bench grinder, then take a socket wrench (just the socket) of the right side to put the grease fitting into it to protect it, line it up carefully, and one quick fairly hard blow with a hammer to drive it in and I never lost one of those then.

 

[JTKub]

my dealer said to put a punch in the opening and give it a few taps to form a lip at the contact point. i havent had any problems yet with grease fittings yet on my 12 yr old 3185. im assuming theyve all been replaced at this point.

Exactly. Peen it on opposing sides with a punch. If you're replacing it with another press-in, apply some Loctite, then peen. In 5yrs, I never lost one on my Cub 2544. Lucky I guess.

Joel

 

[highboy1975]

that sounds better, hit it around the hole. as far as pulling apart a bearing and repacking, i guess that comes down to how much spare time you have.

 

[Captain Ned]

Exactly. Peen it on opposing sides with a punch. If you're replacing it with another press-in, apply some Loctite, then peen. In 5yrs, I never lost one on my Cub 2544. Lucky I guess.

Joel

OK, I'm seeing what I think are 2 separate ideas. You're suggesting that once the fitting is in, an application of a punch at two points to squeeze the hole tighter is the way to go. Highboy1975's dealer idea seems to be to punch in the hole itself to create a ridge in the hole.

I think I like your idea better. Only lost 1 more today while finishing the lube job; this one on a steering knuckle.

Before I understood that these were press-fits, I bought an assorted kit at AutoZone where I got 70 pieces for $12.99. I paid $2.06 per at the dealer this afternoon.

 

[highboy1975]

i think with either idea, your looking at hitting it before you put the grease fitting in to cause more of an interference fit. i was told to use a ratchet extension to tap the grease fitting in. 1/4 inch i believe. if doing it inside the hole would create a ridge, then i like my idea. the idea of peening around the hole sounded better. i was tired and not thinking my thoughts through and that using a punch inside the hole would just open it up more. you want to close the hole up a tiny little bit to give more interference between the fitting and the opening. i would think you'd have to use a pretty blunt punch to create a lip inside the hole. either way should work, it just depends on the tools you have available.

 

[CJ-8_Jim]

A few months ago, I had to replace a number of press-in grease fittings on my GT3235.

I went down to my local Menards home improvement center (not sure if those are by you) and found a variety of grease zerks in their specialized parts bins.

If I recall correctly, the 3/16" press-in they had was too big or two small, but when I went one size bigger/smaller, it fit perfectly.

Can't remember the price, but it was < $1 each... maybe $0.60 each.

Pick up a couple extra... sometimes when I tapped them in, I damaged the head. Make sure you use just enough force (not too much) to seat the zerk and tap squarely & evenly over the head.

All and all... it was pretty easy. Replacing with press-ins made sense -- no risk of thread shavings by tapping/installing threaded zerks. Plus no risk of me screwing it up.

 

[Bird]

Pick up a couple extra... sometimes when I tapped them in, I damaged the head. Make sure you use just enough force (not too much) to seat the zerk and tap squarely & evenly over the head.

I never tap directly on the grease zerk. Instead I take a small socket wrench just big enough to go over the part of the zerk that the grease gun attaches to, but not the base of the zerk. Then I tap on that socket so the rim of the socket drives the base of the zerk. For me, that's easier to keep it straight and I can't damage the zerk.

 

[turnerbend]

To my mind using self-tapping fittings will introduce metal shavings into the bearing. If not, I'd certainly like to avoid the alternative, which would be disassembling every bearing with a fitting, tapping it, cleaning it, and repacking it.

In my mind most grease fitting on a lawn mower are not on bearings only bushing.

 

[Captain Ned]

In my mind most grease fitting on a lawn mower are not on bearings only bushing.

Still have to take them apart to do the tapping job the right way.

 

[mustangsallysdad]

Everyone should have a carbide tipped mining bit (single point), they are the best indexing punch ever devised...work great for dimpling. Got a couple from a friend of mine who works in the mining industry.