Panhead repairs

[MurrayS]

Hi All

Longtime member here but not a prolific poster but now I need a bit of advice on some repairs.
About 2 months ago the genny on my Pan self destructed when the inner bearing failed. The genny drive gear collapsed into the idler gear stripping several teeth and spreading the bits through the cam gear case. The collapse was sudden without warning (well none that I noticed) and I was able to quickly stop to minimalize more damage.

The initial stripdown revealled the damage. Armature, genny bearings, oil seal and all the other smalls that surround it. Drive cog, Idler cog. All ordered. Some of it has arrived but with the slow (Covid) post out of the US I'm still waiting for some parts.

I have taken the cam and gears out of the case as well as stripped the Oil Pump to clean out all the metal fillings. I have found all the teeth missing from the idler gear but not all the ball bearings missing from the genny bearing.

Which brings me to my questions.

The cam, which is an Andrews J Cam has lost the hardning on one of the lobes. So out its goes. Any recomendations on what to replace it with?

A previous owner has done the rebuild that installed this cam. It also has a needle bearing and not the 52 bush. This bearing looks ok but is there a way of telling? Or should I replace it anyway?

The tappet rollers show a bit of wear but not excessive. Is there anything in this area that I should replace anyway regardless of what I think it looks like.

Finally, I have flushed the Oil tank, lines, filter, oil pump, cam case with kero. What about the engine? Is taking the plug out of the left side of the engine and flushing back across to the cam case recommended? I hear that the plug can be difficult to get back in with the engine in the frame.

My skill level is distinctly average and would appreciate any comments or advice.

Got some photos coming, Excalibur will post them coz he's smarter than me.

Cheers

Murray
2017 Deluxe
52 EL
42 WLA

[Excalibur]

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[Excalibur]

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[Excalibur]

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Timing side

[Raytag]

Hi,

I`ve worked my fair share on almost any type of internal combustion engines but basically none on Pans. So take it for what its worth.

The J-grind by Andrews is a neat cam in Shovels for rider who like taking it easy. Easy starting, decent torque. I`d go for it anytime again. I observed that quite a number of Pan jockeys are happy with it, too. Almost any other cam you need to read the specs carefully.

Unless a needle bearing of such size is badly damaged it is IMO impossible to tell whether it still ok or not. That "fingernail-roll-the-needle-test" is at least to me useless and ... that bearing receives some lube from the gear case
I replace them in Shovels & Evos always. No matter what.

Just by looking at the pic that particular tappet is shot. Your 52 doesn`t need to keep up pressure there and I`ve seen far worse but a worn tappet will rock while traveling up an down and and will hammer the new cam so a bore gage for the tappet-blocks is a good idea and I guess a hone job on the tappet blocks may be needed therefore maybe oversize tappets ? You don`t know till you meassured it.

Cause of the nature of the damage I do not believe that debris crossed into the crankcase. The pistons shoving out the fumes into the gearcase and the pump sucks it up. Once the breather bore still looking good I would not open it.
Damages to the breather bore are caused IMO from piston seizures, blown conrod bearings, loose thrust washers on the flywheels or bits of broken valve springs/seals
Because the crankcase is really tight you just can forget about it flushing the crankcase. If there`s something over there 90% of particles will stay there even if you remove the cylinder and flush it with a garden hose.

BTW: Nice bike!

ray

[Hubbard]

When sourcing parts like the timing gears, try to find oem and stay away from tedds junk.Rebuild your tappets if the bores check out as tag said. When you redo the generator bearing put a double sealed bearing in it. If you have to replace the generator cycle electric can't be beat if you don't have oem. You mentioned the po had rebuilt and put the cam in it. How many miles since then? That much damage to the cam lobe would normally take about 300000 miles. Andrews j will be just fine for that motor. Again stay away from tedds junk.When you put your oil pump back, leave the cam cover off so you can make sure the drive shaft turns free. ANY binding needs to be fixed. Be cautious of the thickness of the pump gaskets as too thick can cause return problems. And make damn sure the gasket is correct and doesn't cause the gears to drag.

[Andygears]

I don’t think that cam has 300,000 miles on it! I have an Andrews J in my pan and like the grind/performance. Andrews cams have been mentioned before for “being soft” and I believe the hardening of the cam is at fault.
For the price of shipping, I would return the cam to Andrews and request a free replacement. All they can say is “No”, but you might get a free cam. (As a side note, my Silverado with a 5.3 is in a million pieces in my driveway for a new cam and lifters with the same damage after 180,000 miles). In buying a new cam for my truck, some manufacturers tout that they semi-finish the cam pre’hardening so the finish grind does not exceed the hardening depth.

Why did the generator bearing quit? The mesh on all the cam case gears is important and that includes the oil pump drive and the generator. On mine, the generator was binding and 2 business cards on the saddle freed things up. The more or less radial load from making ‘lectricity may not have caused the failure, but a side load from too tight a mesh could have.

Replace the lifters.

My opinions
Andygears

[RooDog]

"The tappet rollers show a bit of wear but not excessive. Is there anything in this area that I should replace anyway regardless of what I think it looks like."
If you can feel any up & down play in the rollers, it is too much, and need to be replaced.....

Obviously something let go and wound itself around inside the gear case for quite some time causing a lot of damage. The question is what let go first, all the subsequent damage is secondary....
....RooDog....

[MurrayS]

Great advice, thanks for taking the trouble, i appreciate it.

I bought the bike in 2014 and since then have done about 5000 miles. Soon after I got it I took the generator off and replaced the oil seal. With my limited knowledge I believe I did not pay enought attention to setting the backlash correctly. That is probably why the bearing finally failed.

I'm about to order a cam and Andrews J it will be. Currently working my way through a few of the previous threads on the cam chest to make sure I get it right this time.

As an asside, freight out of the US is currently around 2 months, (very frustrating).

Once gain thanks a lot.

Murray
52 EL
42 WLA

[Bone Head]

It's kind of hard (at least for me) to judge surface wear on a roller. So when you order that new cam think about replacing the rollers. New cam new rollers. That way they wear in together.

[MurrayS]

Hi all. More advice please.

After a long break I am back to the repairs on my Pan. It started with a rebuild of the generator (done) and whilst the side cover was off I noticed that the cam, tappets and tappet blocks were worn.

I now have replacement parts on hand including a cam bearing. An owner prior to myself had machined the case and fitted a needle bearing in lieu of the original bush. I decided to replace the bearing and so managed to make my own extraction tool.

Imagine my surprise when I was able to extract the bearing with light pressure on the tool. 

The old bearing shows some evidence of rotating in place but is in otherwise good condition.
The new bearing is an even less of a friction fit and I am able to insert and extract it with my finger. having said that, there is no discernible movement in situ.

Obviously that is not ok but what is the fix?

As I see it, without taking the engine out of the frame these are the choices.

Loctite the bearing into the case? (I can already imagine the collective heads shaking.)

Use shim steel to make a sleeve to enable an appropriate friction fit of the new bearing?

Go back to using a bush? This would mean machining a new bush to fit the case but possibly within my capabilities. If so, is the type of bronze material important? 

Measurements I have recorded are as follows.
Case hole internal diameter 1.066"
Old bearing external diameter 1.065"
New bearing external diameter. 1.064"
Not a lot to see but I'll post some photos later. 

Any advice or comments would be very much appreciated.
Murray
52 EL
42 WLA

[Excalibur]

Murrays pics ....
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[panhead51]

From everything I learned from Herve, he would say that there are 2 solutions either to reload the hole and machine, or to do a new bushing while respecting the expansion tolerances.
He would say to me, you have to dismantle the engine, separate the housings, fit the bushing with a hydraulic press.
And drill a hole to prevent the bushing from turning.


http://panhead51.eklablog.com/reparatio ... 25999102/7

If you replace a bearing, you will have to use a press, on the other hand I am not sure of the exact clearance between the bearing and the hole.

[Raytag]

Personally I `d first get another torrington from another manufacturer eg S&S or Koyo or whoever. Because I`ve made the same experience on Shovel engines with el cheapo torrington. The one from S&S was bigger and therefore a tight fit.

If making a bushing from stock you need to ream or hone. Some using a scraper. Peening that bushing is another matter.
Materialwise personally I go for C932 https://morganbronze.com/wp-content/upl ... bronze.pdf
C932 is easy to machine. Carbide preferred, HSS possible, dry, moderate speed & feed
Most shops and I believe the big players using C954 by now https://morganbronze.com/wp-content/upl ... bronze.pdf
Working on a lathe with C954 is fairly easy but milling and drilling can be a bitch. Sharp, hardened, uncoated drill bits are a good choice.

Maybe some others here will have a better idea?

Ray

[socalrider]

If you are going to replace with a bushing, assuming that bushing would be made to factory inside diameter specs, I believe that would require a different cam than the roller bearing type cam, which would also require a different bushing in the cam chest cover . In changing these two bushings a line ream/ hone would be called for for proper alighnment of the cam. A line ream/ hone requires splitting the cases. I could be wrong in all of this but before you buy your next cam it’s something you may want to research a little further. In my opinion the bushing was a much better design than the needle bearing. The worry of the needle bearing grenading is nonexistent.
.