Crack in engine case-primary flange

[jdmboyd]

Hey folks,
Hope everyone's doing well.
Found something new today: there seems to be a crack on the engine case where it mates the inner primary. Is this serious/any ideas?

As always. Thanks for your help.

[JBinNC]

That is a common problem. Comes from loose motor mount bolts, loose or missing or stripped primary screws, or using a chromed or aftermarket inner primary where the machining at that interface is bad, or the chrome has built up on the edges.

It will leak despite almost anything you can do with it. Sure fix is to take the motor apart, weld it up, and machine it back to original configuration.

Lots of bikes get converted to belt primaries so no oil is needed and that eliminates that crack as the source of a leak.

I have contemplated cleaning a crack like that really well with acetone, lacquer thinner, and/ or brake cleaner and then filling the crack with Loctite wicking threadlocker. But I have not tried that yet.

Jim

[7and7is]

On that note what about JB Weld?

[Dragstews]

Ron Trock use to made a steel ring, installs into a machined cut ...



I've installed a few, they work really well ... "No welding" is needed for install ...



VT is making them now ..





Alternator Repair Ring ... Price: $145.31
IN STOCK NOW!
VT No 16-0692

( JB is a lot cheaper, but, will not last very long or 609 Green)

[JBinNC]

Cheaper to weld it up and machine it. The ring works, but it's a lot of expense for no better outcome.

Jim

[confab]

Mine has that crack and someone attempted a welding repair that isn't very good.

I like to run ATF in my primary, so I isolated it from the engine oil and sump and blocked the lines, cleaned it really well with brake cleaner and blew the crack out good.. Then rubbed some permatex "ultra" silicone into it really well with a rag.

With no pressure, it works fine and it has for several years now. Silicone is flexible and works well for such things where a hard material like JB Weld might blow you shit after several heat/cool cycles.

You would be amazed at the casting porosity you can fix with a good cleaning and forcing silicone into the affected area, provided there's little or no pressure involved.

Warning: If you do this, it will probably hose up attempts to weld it properly in the future.

Mine was welded on the inside and then ground for clearance. A top notch welder might be able to do something with it on the bike.

Good luck!!

[jdmboyd]

All, thanks for the input. Also, sorry about the newby mistake (6 yrs?!?), this is my 1980 FLH 80, but you new that.

My primary is also sealed. I had been running 20W50 in there since I've had it and decided to try ATF after the rocker cover gasket R&R in last month. I don't think it's been leaking here; I've been slathering that shoulder seat and o-ring with gray form a gasket and it has seemed to work in the past.

I took the primary back apart yesterday because a drip seems to be coming from the inside primary, about half way back where the front trans bolts and a case plug are; I re-teflonned the plug yesterday. Can't see the best from the bottom looking up, even with it hoisted up, but the leak seems to be coming down from that neighborhood.

I'm waiting for a new gasket and o-ring for the starter gear mount. When I put it together I'm thinking about temporarily extending the the oil lines to mount that pesky oil tank up above the frame so I can get a good look down from behind the primary and see any leaks from there. Couldn't ride it that way of course, but could run it there on the stand and see what I could see.

If this continues to be an issue I may have to bone up on the dry primary belt option. Question: can you run a dry belt inside a closed primary, or does belt width force you to an open primary? The thought of tearing the motor apart and getting that flange welded and machined sounds like a long winter job and we've past that for this year up in VA.

[confab]

They make narrow primary belts and kits to run inside housings.

In fact, I believe the Sturgis was a factory, version of that.. Wasn't it?

[docmel]

[QUOTE=confab;856113]They make narrow primary belts and kits to run inside housings.

In fact, I believe the Sturgis was a factory, version of that.. Wasn't it?[/QUOTE

Yep The "B" in the model stood for belt (Primary) Lotsa folks run belts inside both tin and aluminum primaries

[confab]

They make narrow primary belts and kits to run inside housings.

In fact, I believe the Sturgis was a factory, version of that.. Wasn't it?

Yep The "B" in the model stood for belt (Primary) Lotsa folks run belts inside both tin and aluminum primaries

Yeah, I thought I had seen them like that. They recommend the thinner ones.. 3/4 Inch, maybe?

I'm sure I've seen 3/4 inch setups in the stock primary..

[JBinNC]

[QUOTE=docmel;856117]

They make narrow primary belts and kits to run inside housings.

In fact, I believe the Sturgis was a factory, version of that.. Wasn't it?[/QUOTE

Yep The "B" in the model stood for belt (Primary) Lotsa folks run belts inside both tin and aluminum primaries

I believe the "B" in the model designation stood for the belt final drive, although the Sturgis and the belt WideGlide had both belt primary and final drive.

Jim

[JBinNC]

Yeah, I thought I had seen them like that. They recommend the thinner ones.. 3/4 Inch, maybe?

I'm sure I've seen 3/4 inch setups in the stock primary..

A 1 1/2" wide belt primary drive will fit within either tin or aluminum primary covers. The aluminum primary covers need to be well vented, or the belt life will be short. (I have had that sad experience.)

Jim

[jdmboyd]

Oh, good, so a stock primary can hold a belt drive inside; good/great to know. For some reason when I think of belt drive I see a 3" wide, open primary set-up, which isn't the look I'm after with this Electra Glide.

Jim, if my plumbing efforts fall short I may want to pursue that 1.5" set-up. If so, what would qualify as adequate ventilation, multiple 1/2" holes on the inside?

Thanks again; y'all's knowledge here is spectacular.

John

[JBinNC]

Vented inspection and derby covers should suffice. There are also outer covers with large vent windows.
The inner primary cover can be left as is.

Jim

[Dragstews]

https://jamesgaskets.com/products/jg...2074fb91&_ss=r

NOTE: Here's another common sealing problem with a James Gaskets cure.
How often have you found a broken sealing groove between the engine case and inner primary cover?
Over time that lip gets bent, broken or damaged and the result is a nasty leak past the O-ring.
Repairing the groove itself is difficult at best and complete case replacement is out of the question. Enter the James Crankcase Saver Kit.

The James Gaskets Crankcase Saver Kit is a neat fix-all gasket to solve this problem. It'll work regardless of the condition of the lip.
The lip can be completely removed if you want. Using a rubber-covered steel base material, James came up with a gasket to seal the two units at the flange surfaces. The gaskets are coated with a micro sealant.

Installation requires no additional sealers and each gasket includes all the required lock tabs for the primary installation.The Crankcase Saver Kit is available for Evos, Twin Cams and Shovelheads.

[SteveJ]

In the shop where I worked the owner came up with a way better solution for this all too regular repair.
He is an excellent tig wlder , engineer and machinist.
The weld repair was done on the ring while the engine was still in the bike as per usual aluminum welding procedure.
Tooling was made to attach an electric die grinder.
The weld was then machined on the bike turning an overly expensive repair into a 3-4 hour job.
This is the way to do this job for a properly equipped custom bike shop.
Pretty fuckin' cool rotating the die grinder around the ring repairing it perfectly.

[10scDust]

Mine has that crack and someone attempted a welding repair that isn't very good.

I like to run ATF in my primary, so I isolated it from the engine oil and sump and blocked the lines, cleaned it really well with brake cleaner and blew the crack out good.. Then rubbed some permatex "ultra" silicone into it really well with a rag.

I did that too with the Permatex. It's still holding up.

I also isolated the primary housing oiling system but just use 50 weight motor oil. If you can shut it all off for a belt drive, you can plug the galley entries on the inner. The oil is really there to lubricate the chain, the clutch plates will run wet or dry.

I wonder, how do your clutches react using transmission fluid. I have read about contemplating results making clutches too sticky, I think I read. Just never tried.

1973 Shovelhead Superglide.

added edit:

My experience with the narrow belt is it works great, but it needs to be kept cool.
The vented covers gave me a couple years before losing belt teeth.
So now they are both back to oil bath chains, my 1973, and my 1971 FLH.

[jdmboyd]

That is a common problem. Comes from loose motor mount bolts, loose or missing or stripped primary screws, or using a chromed or aftermarket inner primary where the machining at that interface is bad, or the chrome has built up on the edges.

It will leak despite almost anything you can do with it. Sure fix is to take the motor apart, weld it up, and machine it back to original configuration.

Lots of bikes get converted to belt primaries so no oil is needed and that eliminates that crack as the source of a leak.

I have contemplated cleaning a crack like that really well with acetone, lacquer thinner, and/ or brake cleaner and then filling the crack with Loctite wicking threadlocker. But I have not tried that yet.

Jim

Looked closer and all 4 crankcase holes have been helicoiled, and the one at ~ 1:30, over the cracked flange, is stripped, both the safety wire bolt (worn down) and the coil insert (wouldn't hold the other sharp toothed wire bolt). Picked up some 5/16-18 inserts today and a pair of new safety wire bolts should get here this week.

For a belt drive, the vented derby and access hole sound right, a machinist could cut slots under the horizontal fins on each and wouldn't weaken the inner with excessive Swiss cheese. Looking at the plethora of belt drive kits out there, is there a chain/belt tightener/idler like the nylon runner on the chain drive? Or do you just fit the belt tight and run it 'til it stretches too much?

[Dougtheinternetannoyance123]

Im not a expert in Harley cases, But I have repaired a lot of engine castings, I mentioned in another thread I used to work at a Aerospace casting company, Mostly Stainless and Titanium, But I did a side hustle repairing vintage car & motorcycle parts.

Castings vary, But theres a technique to properly weld them. I also worked for a while at a vintage shop and the old school owner would gas weld alloys and made it look easy. But the TIG welders I worked with, some of the best in the US.

We found to properly weld a cast aluminum engine or primary, trans or other casting, VERY Scrupulous cleaning, and even heat the case and clean again. Some castings are more porous than others, so often we cleaned, V'd the crack or ground a bevel
and when striking the arc with the TIG tungsten tip, you could see oil ooozing out of the casting. This then explodes and splatters contaminating the Tungsten. Stop, clean, repeat. Sometimes it took multiple attempts to get a clean weld.

TIG guys get pissed when you contaminate their gear. Some welds better than others. Some alloy has a mix of alloy so it can be challenging, Plus you have to use the right rod. If you dont the weld area is obvious with a dull cast surface and some shiny tin foil looking blob, its obvious welded with wrong alloy rod. May not make a difference if covered up, But it can be a problem.

In most cases, Preheating a alloy casting and bolted to a fixture or heavy steel plate is the way to go. (Thick enough it doesnt warp and crack the casting) Consult an expert but ive screwed up some castings doing it wrong. If you dont, will warp the shit out of them even if you get clean welds.

I have fixed bearing races and areas like that on a few castings, Never fails some warpage and distortion of the bearing bores requiring machine work to restore, sometimes that critical bearing crush tolerance can be lost which is a whole different set of problems to repair. Early Triumph engine castings frequently crack or break there, And I have one coming up on a set of 1948 castings.

If it were me, Id seriously consider that steel ring if Dragstews recommends them. Sure beats the alternative, While I have used JB weld on a number of different things, It looks to me that sooner or later that crack will get worse, so no, I wouldnt leave it. Cracks dont repair themselves.

As to belts, I love belt drives, dont overlook MOST belt drive setups weight shit ton less than the stock chain setup. Thats a great way to increase speed and power. When the motor isnt slinging a heavy ass weight outboard of the engine, thats power thats not wasted. Usually a well done belt drive can be felt in the Butt Dyno. Not to mention bearings and trans live longer. Many trannies have a long shaft and a lot of weight slinging around is hard on a trans. Lighter is better. Belts rule.

Those who flog their rides hard, especially racing, run outboard bearing supports, If you look at how much flex and wobble on a speed camera, it will scare the hell out of you.

As well, Belts when hot run tighter, not looser. A well ventilated or open belt is a happy belt. They live longer too. A belt ran too tight will kill bearings, strain trans and wont last. Setting belt tension takes some practice and research. I love belts on my final drive on the Evo sporties and Buells. If I could, Id run belts on all my old vintage stuff. I run belts on primaries whenever I can. Love them.

[confab]

is there a chain/belt tightener/idler like the nylon runner on the chain drive? Or do you just fit the belt tight and run it 'til it stretches too much?

I have seen guys fab tension rollers, and some kits may have them stock? They make sense. The one I saw, I think was using the original saw teeth from the inner primary adjustment for the chain shoe to take the slack out. It appears to be a free form kind of thing, as they don't seem to need (and you probably DO NOT WANT) an extreme amount of tension.

I have heard 1/3rd "twist" in the belt, is properly adjusted.. And too much unnecessarily loads the crank and trans bearings. I bet this would REALLY be a no-no in pre-timken engines.

Also, extreme tension might be more prone to damage your pulleys in the event you ingest a rock or something.. So, I think I'm going to only run the tension I require to keep it on the pulleys and no more.

(Others may know more. I'm a belt drive noob, still setting up a custom system for my 45 project.)

Otherwise, the Mrs picked one of these adjustable trans mounts up for hers.

https://old-stf.com/products/harley-...mounting-plate

It lets you draw the transmission back with a couple of allen bolts, then lock it down to make belt adjustment easier.