Adjustable Pump Gear quality control question

A

AMS247

New member
I just installed an adjustable pump gear for the P7100 and am having concerns.

Off the truck, the interference between the gear and inner hub seemed perfect, I inspected everything and everything looked great.

After installing the gear on the hub, I'm having issues removing the outer gear.
I have removed all 6 Allen bolts plus the smaller timing Allen bolt. Even with a gear puller, this thing is having troubles coming off.

There is no bind on the gear, as I can bar the engine over fine. I attempted removing the gear with a puller since it seemed too tight. Even then the interfecerence seemed to be too much. I started seeing metal from the threads where the bolts for the puller go into. So o called it a night.

Is this at all normal?

I've reached out to the business (not mentioning names) and no one is working today to give me a solid answer since they havent seen this. So I'm left to wait.

What does every one think?
 
We've had a couple adjustable gears that were questionable on how well they centered the part during machining.
 
I don't have any pictures at this moment. What pictures should I take to show? The gear is currently mounted on the truck, with difficulty removing. It is an aftermarket gear that has been machined. Not a factory gear that has been machined.
 
What did you torque the hub to? When you draw it up on the taper, it will expand it slightly on the OD, which could be causing your interference issue.

I didn't have any issue removing the gear from the hub when it was installed on my pump. I have an Eat Soot adjustable gear.
 
Rotate the engine with all of the bolts out. See if any position allows it to come free. We had some concentricity issues with some like I mentioned that made me cringe.
 
Tate said:
What did you torque the hub to? When you draw it up on the taper, it will expand it slightly on the OD, which could be causing your interference issue.

I didn't have any issue removing the gear from the hub when it was installed on my pump. I have an Eat Soot adjustable gear.
Click to expand...

I torqued it to 144 ft-lbs.

I bought this from a large, reputable company. That was my only thought was maybe the steel that they used is soft enough to expand against the taper creating the amount of interference that I am seeing... idk.

Before I installed the gear, I did pull the bolts and spin it around and everything seemed fine.

I was timing my pump with the dial in the pump at the time, and I noticed attempted to pull the outer gear bumped it in my process. If I am recalling right, I started actually rotating the pump with the outer gear completely unbolted to fix the timing. I'll check and verify tonight.
 
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I went back at it tonight to remove the gear and took pictures to go with. Originally, when I was using my gear puller I saw trace amount of metal shavings and I had thought that I was stripping the threads in the outer gear.

After I removed all bolts, I rotated the engine feeling the gear to feel if it was out of round and had any loose spots that might just have the gear pull off by hand and it wasn't so. I even installed the puller and rotated the engine as there was a pulling force on the gear, and that did nothing as well.

As you can see in the pictures, the metal shavings that I originally saw were coming from the hub surfaces between the outer gear and mounting flange.

Since I examined this all off the engine before install and everything slipped over eachother fine is it safe to say that the inner hub is made from a metal soft enough to expand just enough to make this fit that tight?

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None of the pics opened for me. When I received my gear I had concerns on the hub centering. I asked the builder what clearance from hub to gear was acceptable, the answer was I don't set them tight, they will bind...(no clearance was given) I guess pick your poison. If it rotates on the hub but is snug I think your good. Shouldn't have to remove it to many times, But I do understand your concern….

IMG 3623 - YouTube
 
It's amazing because I had never read anything about quality control on these gears. It only seemed like an upside to buy one.

Hmmmm, idk how to post an image then. I was intending for them to post being hosted from Imgur.

I'll give links to Google drive, that should work I hope.

20190220_211017.jpg - Google Drive

20190220_211611.jpg - Google Drive

20190220_212801.jpg - Google Drive

20190220_212806.jpg - Google Drive

20190220_212821.jpg - Google Drive

20190220_212853.jpg - Google Drive

20190220_212933.jpg - Google Drive

20190220_212942.jpg - Google Drive
 
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Pretty normal for people to accept most parts fit like chit in the diesel aftermarket world. We had a set of MBRP up pipes for a 6.0 we ordered for a customer that looked like a 1st grader welded. Wire poking through inside of the pipes and pieces of pipe hanging inside from poor fitment. Customer said the last set was like that and wanted them. He said in so many words "Maybe this set will at least line up properly".

Try one of the 2nd gen swaps from the "budget friendly" company. Everything rubs and touches. Hot things on oil lines, air filters with grid heater relays poking into them. Their response: "Put some protective stuff on anything touching so it doesn't rub through then".

Frustrating dealing with a lot of the crap out there to say the least.
 
Yeah, I'm not happy with the product. Thinking about it, it's actually useless and really just a paper weight. So the gear as we know is a tight fit around the inner hub. So tight, that it's press fit and hard to remove.

The gear is also not a straight cut gear, so in the removal process the gear will shift clockwise as it stays aligned with the cam gear teeth.

On a factory gear, the gear is a taper press fit so using a gear puller, even a fraction of an inch releases the gear and it is no longer moving the pump.

With the adjustable gear, at the time of my original attempt to pull the outer gear off I had a dial gauge in the delivery valve. Even pulling the gear approximately 3/16" I saw the dial gauge read the the pump turned the barrel 1.5mm more in timing. And the ledge of what this outer gear is pressed against is quite a bit so pulling the gear off as it turns the pump following the teeth of the cam gear is going to really mess the timing up.

Which to me, makes this gear useless and seems like the factory gear will be a better route...
 
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Do you have a micrometer set? It would be worth measuring the hub diameter as well as the bore in the gear. Looking at the rub on the hub, it looks like it has a bit of a reverse taper on it as it sits, and I'd guess an interference of only 0.0005". If both pieces are concentric to their bores, then clean up the hub where its rubbed while still installed on the pump. Shouldn't be much to get it to size, IF you are wanting to make this one work.

It's not necessarily a "soft" steel because it expands on a taper, thats just a fact of being an elastic material. We use tapered sleeves on coupling bolts on power generation turbines because they expand on a taper.

Your point about the pump turning while removing the gear, while correct, I would say is moot once you get a proper working adjustable gear. I doubt you'll be removing your gear very often, and once it becomes a slip fit, won't turn the pump anyway.
 
Tate said:
Do you have a micrometer set? It would be worth measuring the hub diameter as well as the bore in the gear. Looking at the rub on the hub, it looks like it has a bit of a reverse taper on it as it sits, and I'd guess an interference of only 0.0005". If both pieces are concentric to their bores, then clean up the hub where its rubbed while still installed on the pump. Shouldn't be much to get it to size, IF you are wanting to make this one work.

It's not necessarily a "soft" steel because it expands on a taper, thats just a fact of being an elastic material. We use tapered sleeves on coupling bolts on power generation turbines because they expand on a taper.

Your point about the pump turning while removing the gear, while correct, I would say is moot once you get a proper working adjustable gear. I doubt you'll be removing your gear very often, and once it becomes a slip fit, won't turn the pump anyway.
Click to expand...

I'll measure everything out and post it up. I'll run a dial on the gear too as I turn the crank to see if there is any run out.

I gotcha.

I guess I just don't see that much value on buying a gear thinking that I could pop it off easily when I really can't.
 
Upon pulling the hub off, the inside keyed area has the key inprinted pretty good on the hub. Also, the force on that key pushed material up right where that key is located causing more interference with the outer gear.

In the pictures linked, you can see both things that I am pointing out.

In the end I installed the factory gear and sent the adjustable gear back to the business I purchased from.

20190225_134500.jpg - Google Drive

20190225_134434.jpg - Google Drive


view


view
 
The key used was provided with the adjustable gear, which also spec'd out to the Cummins pump key that I had as well.
 
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