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Primary chain case leak

I have a 1995 FLHTC Electra Glide Classic with 48,000 miles on it. I have maintained it very well.

Recently, I noticed some fluid under it so I had all the seals changed associated with the primary chain case.

When I got the bike back it still leaked and after redoing it four times it still leaks.

Looks like the leak is coming from a bolt on the back bottom where the primary chain case bolts to the bike. It is not leaking from the "outer" primary chain case cover.

When I jack up the bike and look under it I can see fluid which appears to be leaking out of the end of the bolt.

I am thinking that I should put Teflon tape on the threads to prevent this leak but would prefer to have somebody with more knowledge comment on this.

My cell phone is 248-361-7911 and I am in the Detroit area.

John
 
Thank you TQ.

I do have the repair manuals but I did not read them because I had a skilled mechanic do the work so I assumed he knew what he was doing.

The RTV sounds like a better idea than the Teflon.

Thank you so much.

John
 
Just as a point of information...from my own experiences....Teflon inclusive products are not your best choice around petroleum based or glycol based products.
You will have much better luck with both stopping and preventing leaks with either an RTV or just plain old Permatex
 
Thank you TQ.

I do have the repair manuals but I did not read them because I had a skilled mechanic do the work so I assumed he knew what he was doing.

John,

You know the old saying about ASS ... U ... ME!!

We may come across on this forum as "hard" on the dealerships. There are plenty of good folks and experienced wrenches working in the shops. Problem is, it is a gamble. You might get the great mechanic that really cares about the bikes he works on, or you may get the newbie who has been through training, but is OJTing on YOUR bike, and is under pressure from the Service Mangler to "just get it done"!!

So, read your book about anything you are gonna have the shop do for you, know what you are talking about when you go see them, and check some of the obvious stuff when you pick up the bike (like fluid levels - engine and tranny at least if they have been in there). Things happen!!

TQ
 
John,

Do you have the HD Factory Service manual for your model and year? Check in downloads above and see if we do, otherwise you might contact Gary12850 about getting one.

My books ('91 Dyna and '03 UC) both indicate that the threads on the three lower bolts found behind the clutch basket that secure the inner primary to the tranny and have keepers on them should be coated with RTV when installing. The book also says previous to this, that the three standoffs on the tranny should be coated with RTV BEFORE putting the inner primary on. I would use RTV rather than teflon tape on the bolts as instructed in the manual.

I have had my primaries off and on my bikes repeatedly, and never had a leak develop there when I followed the instructions in the book.

Good luck on this.

TQ

As I noted earlier, I have the HD Factory Service manuals and you are right. They say to "coat" a bunch of the screws connecting the primary chain case cover to the rest of the bike.

My expert was not a Harley Dealer but a guy who works at a Harley Dealer and who does work on the side. He said he has done hundreds of bikes without coating the bolts but he said he puts RTV around the screw hole.

Anyway, I have printed out the pages in the manual and he has agreed to do the job again at no cost so I am betting we will not have any leak after we coat the bolts.

Further, I plan to trailer the bike to his place and back so the RTV will have plenty of time to cure and will not be affected by the heat of a running bike.

One thing I am still concerned about is the proper way to clean the surfaces and the bolts so that the RTV will stick. I am guessing that he will continue to use "brake cleaner" and then paper towels to do the cleaning

Thank you again,

John
 
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One thing I am still concerned about is the proper way to clean the surfaces and the bolts so that the RTV will stick. I am guessing that he will continue to use "brake cleaner" and then paper towels to do the cleaning

John,

I just scape off the old gasket material (RTV) with a small paint scraper and then clean the surfaces with mineral spirits followed by methanol. The objective is to degrease the surfaces so the RTV will bond. Your guy's approach of using brake cleaner spray will accomplish the task.

TQ
 
I have purchased some Permatex 66B RTV clear silicone and the technical spec sheets say that the parts should be cleaned with spray on brake cleaner and then blown and wiped dry. The spec sheets also say that the RTV takes 24 hours to fully cure so I am thinking that I will not add the fluids until the next day and, of course, I will not drive the bike for 24 hours since the heat and fluids may affect the curing of the RTV that I plan to coat the bolt threads with.
 
I have purchased some Permatex 66B RTV clear silicone and the technical spec sheets say that the parts should be cleaned with spray on brake cleaner and then blown and wiped dry. The spec sheets also say that the RTV takes 24 hours to fully cure so I am thinking that I will not add the fluids until the next day and, of course, I will not drive the bike for 24 hours since the heat and fluids may affect the curing of the RTV that I plan to coat the bolt threads with.

I have been using the term RTV as a generic term (like Kleenex! After all, who says "Facial Tissues"?) for any of the tubes of "form-a-gasket". I personally look for the "high temp" versions when I get some (O'Reilly's), and have a variety of brands out in the garage. The whole point is to make sure that you use any one of the different brands that are designed to be used between hot mating metal surfaces (not weatherstripping adhesive). Be generous when applying the "RTV". And let it set up for a few minutes on the standoffs before putting the inner primary cover on (I put it on both the stand offs AND the back of the inner primary cover). The bolts you can just put a bunch of goo all the way up the threads and all the way around the bolts' threaded area (put the keepers on the bolts first!!). When you put the bolts in the holes in the inner primary cover, start a thread or two, and then wipe any excess off the inner primary cover bolt hole area. Screw the bolts in finger tight, put the ones in the front of the inner primary cover to the engine and screw them in handy tight. Get your torque wrench out and follow the sequence in the book to torque the bolts. Go to the final torque value in stages (final-10ft.lbs., final-5ft.lbs, and final). DO NOT OVER-TORQUE AND RISK STRIPPING THE BOLT HOLES. But you can use the high value of the range as your "final".

By the time you have finished putting everything back on the bike and putting fluids in (premium synthetics in the engine-engine oil and tranny-gear lube, and Formula Plus or Spectro Primary in the primary), the bike can be ridden. There is no significant pressure in the primary. Just fluid sloshing and being slung around. The heat of the engine and transmission will help accelerate the cure of the "RTV". But if you want to be super conservative, let it cure for the time indicated on the package.

Good luck!

TQ
 
Here is the final comment on the primary chain case leak:

RTV stands for Room Temperature Vulcanization.... which means the thermoset silicone compounds must cure at room temperature. There are also LTV and HTV for the kinds of thermoset silicone compounds that cure at Low or High temperatures.

Room Temperature Vulcanization refers to a specific curing process involving room temperatures (65 to 75 degrees F). It is a chemical process in which polymer molecules are linked to other polymer molecules by atomic bridges composed of sulfur atoms. The end result is that the springy rubber molecules become cross-linked to a greater or lesser extent. This makes the bulk material harder, much more durable and also more resistant to chemical attack. It also makes the surface of the material smoother and prevents it from sticking to metal or plastic chemical catalysts. This heavily cross-linked polymer has strong covalent bonds, with strong forces between the chains, and is therefore an insoluble and infusible, thermosetting polymer or thermoset.


I am guessing that using the bike before this process takes place would create too high heat and screw up the curing...... as would leaving it outside in the cold air. Both of these "non-room temperature" curing situations would affect the performance of the sealant in a bad way.

Because of the low outside temperatures in November, when I got the bike home in the trailer I put a spotlight in the trailer focused on the spots where we put the RTV and left it there for the 24 hours of curing so I am guessing that it cured at room temperature. We will know next year when I will put the lubricant in the chain case. I did not want to add the lubricant till AFTER the curing process since it might affect it in a bad way also.

I will let everyone know in April or May when I fire the bike up again for next season.
 
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