90 degree gear drive wear

[WarWagon]

I am working on a 12 DJC Onan 12KW generator and have severe wear on the gear drive for the injection pump. The camshaft gear that drives the pump is available and replaceable, but, the injection pump gear is unobtainium. I bought a parts set just for the injection pump, but, it's starting to show wear although not as bad.

It's a big job to rip the camshaft out to change one gear. I am not thrilled to use parts showing wear.

Is there a coating that could be applied to the used IP gear to help? Or would I just coat a new camshaft gear and run the newer pump as-is?

Current set



IP



IP gear




Cam gear




Pump from a parts unit and it's gear wear.





I would have just swapped the complete generator out with the parts unit but it drowned in the desert. Water in exhaust.



After knocking the rust off it needs to go OS or sleeved. Not worth the $$.

 

[Twisted Steel Performance]

Can the gear be removed?

Looking at the pics, what part is warn, the teeth or the boss , what would you want repaired?

I'm not aware of a coating that would "fix" the boss/ smooth part but maybe weld and turn it back down?

 

[MrMarty51]

I regularly use this stuff.
That new engine will get this as soon as the break in period is over.

https://www.amazon.com/Liqui-Moly-2009-Anti-Friction-Treatment/dp/B00LU3Z2MC/ref=asc_df_B00LU3Z2MC/?tag=hyprod-20&linkCode=df0&hvadid=692875362841&hvpos=&hvnetw=g&hvrand=11497123007594738282&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=1014485&hvtargid=pla-2281435179258&psc=1&mcid=e1287e614a4b3a2886338947772d843d&hvocijid=11497123007594738282-B00LU3Z2MC-&hvexpln=73

I once dismantled a Dodge 360 engine, 250000+ miles. The PO bought the car new and used it on the road. As soon as the break in period was accomplished He went to using a Standard Oil product that was moly lube enriched.
That was a mistake dismantling that engine. Every bearing and the cylinder walls were black and not one sign of scuffing or wear.
IDK if Standard petroleum is still in business, not here they are not, so I guess this is the next best thing to that product.

 

[Twisted Steel Performance]

Those chips in the teeth are easily fixed, tig, then file.
Would be a good idea to see how hard the gear is to know what filler rod might be best to use...

 

[Will L.]

Weld & file is best. Any epoxy type stuff or jbweld will NOT hold up.
If you don’t know how to test hardness:

https://www.amazon.com/TSUBOSAN-Japan-Hardness-Tester-Checker-HRC40-HRC65/dp/B000TGHFLC/ref=mp_s_a_1_1?crid=L1NIIGEHK9ZA&dib=eyJ2IjoiMSJ9.nwQ1qEwEcsszgWirYOD8MTQD8V0zfAlQFgzwmZtke-LPtBBw5XFY1LTjr7CbIIgjPyqp3NYFHX0Kxof_ebz2gfQJ2mnH4wZNbUIUgzPeecB0G2a5HsW5LPho4-09jg5WYGmbljDqgmRQSn9IUVUkJURrao249NlejN0kv5XIqfiEmOOQDLO9lshw7zeIxrdQIDBiazgroYah8IREsih0-w.tkqXs_xeV5CRFu5R5Yfky9j69k9-RldSizgF_NZF9FQ&dib_tag=se&keywords=metal+hardness+files&qid=1727281996&sprefix=metal+hardness+files+%2Caps%2C222&sr=8-1

 

[WarWagon]

The cam gear is replaceable as part of a big job. The IP gear is able to be removed from the pump, but, it's the part I can't get new. The gears are the only item needing repair.

My question is coating a new cam gear going to do any good with the existing IP gear wear?

 

[Twisted Steel Performance]

No sir..

 

[jrsavoie]

No sir..

What about after the gear was welded and filed?

 

[Twisted Steel Performance]

Yes if both are not chipped.

 

[Twisted Steel Performance]

Joshua if you can remove the chipped gear I'll try and tig the bad spots and fix it.

 

[dbrannon79]

That's an odd way to drive an IP. I've not seen this setup before. I wonder if something could be made to replace the IP gear. maybe of a softer but hard material that wouldn't wear the cam gear out. or vice versa. maybe something made from billet aluminum

 

[WarWagon]

Wasn't really looking just checking if it was even available and I tripped over a NOS IP gear. I ordered both gears as NOS as the cam gear is more common to find.

Do you coat both gears?

Does the coating affect the clearance of the gears? If so I would need to add a shim.

Cam gear major job to get it swapped. Pull camshaft...



IP Gear. And it's going to be real fun to install it. Requires a press to put clips in...

 

[Twisted Steel Performance]

It's better to coat both but not absolutely necessary.

 

[WarWagon]

The fun part: The retaining ring requires a special tool, easy to make I read , to install with a press.