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Thread Like Summary
dave jones, JubeePrince, Oil Changer, splash
Total Likes: 14
Original Post (Thread Starter)
#804386 04/07/2020 11:02 AM
by splash
I tried to tighten to 22 foot pounds as the manual says to but the dome nut on the intake side of the oil feed tube stripped out I believe. This is causing an oil leak. Has anyone had this problem and how did you fix. At first I thought it could be bottoming out but I don't know. Why would it not fit the same? I haven't done any mods to it. I did not torque down the oil feed on the exhaust side down to 22 because of this reason. No leak from exhaust oil feed.

Does anyone know the thread size on the rocker spindle? Thinking about just putting a regular nut on it if I can simply get it at the local hardware store but unsure of the hollow spindle.
Liked Replies
#804471 Apr 8th a 01:06 AM
by TR7RVMan
Rotate motor until valve is fully open. Rocker arm puts pressure on shaft & reduces spinning.

Anneal all 4 washers. Smear oil or grease on washers & threads.

Trial fit nut & make sure nut tightens freely, fully be hand. If you need wrench threads are NOT good. Also verify nut screws on far enough to tightly pinch banjo & washers before bottoms out.

To anneal washers, hang washer on coat hanger wire. Heat red hot with burner of gas stove or solder torch. Drop washer into cup of water to remove black scale.

Hole in washer gets smaller with every use. File hole as needed. Washer must fit freely, not snugly. The copper needs a place to squish to. Tight fitting washer tends to leak easier.
2 members like this
#804403 Apr 7th a 02:37 PM
by koan58
If the nut has stripped you should be able to see evidence.
Presumably the nut just keeps spinning when you try to tighten it?

For example, if it has been stripped just now, remains of nut threads stuck in the spindle threads
or a tail of thread peeling out of the nut.

The threads inside the nut should be visibly very shallow and flat-topped.

I've never known the spindle threads to strip, they are usually much tougher/harder than the nut threads.

It can happen that the spindle spins before full torque is reached. This can deceive you into thinking the nut has stripped, so is worth checking.
Put a finger on the other end of the spindle while turning the nut (or put a mark on that end and see if it moves).
If this is the problem (unusual and hopefully not), let us know. The solution will be more involved than just a new nut.

The copper washers should be in decent condition (ideally new) and should be annealed before EACH attempt at tightening.
A washer goes each side of the banjo, and the surfaces of the banjo and rocker box must be smooth/flat.
It may also be worth checking that the leak isn't due to a hairline fracture near the pipe/banjo junction (a longshot).

At least you've got a running bike to leak! Good luck!
1 member likes this
#804404 Apr 7th a 02:40 PM
by JubeePrince
Remove the oil line banjo and check threads on the spindle and nut. If the nut threads on ok but never tightens, chances are the spindle cap is rotating in the rocker box, not bad threads.

If that's the case, there are a number of fixes that can cure this.

1 member likes this
#804538 Apr 8th a 06:10 PM
by R Moulding
R Moulding
I started using small Dowty washers here sometime ago. The given Torque spec has always seemed a little optimistic to me so I nip them up with a short spanner. I've also had aftermarket domed nuts made from a material softer than cheese.

It's also important to check that the banjos are not twisted and hooking on the threaded section stopping them from seating properly.

1 member likes this
#804569 Apr 8th a 09:00 PM
by JubeePrince
after the cleaning dries, sprinkle talcum powder where you suspect the leaks are, start it up and look for the wet spots from the oily powder.

1 member likes this
#804640 Apr 9th a 12:22 PM
by R Moulding
R Moulding
There is another possibility assuming the bike is still single carb. Two of the manifold stud threaded holes are open into the head meaning if the stud threads are not sealed you will get oil leaking along the threads. Worth double checking before you whip the head back off.

1 member likes this
#804692 Apr 9th a 06:40 PM
by HawaiianTiger
I don't suppose that anyone has missed the fact that our man Splash is now a card carrying member of the RUNNING Triumph club and has successfully completed a ground up engine rebuild.
I think that's cause for some celebration clap
Oh, right, he has an oil leak. facepalm
Ya done good Splash. Yeah there was some frustrations, but now you can make those memories fade away with wind in your face.

1 member likes this
#804696 Apr 9th a 07:45 PM
by Irish Swede
Irish Swede
Regarding rocker spindles:
I am considering grinding a small flat spot in them, where they pass through the center rib inside the rocker box,
then drilling and tapping that rib for a set screw.
Then peening the hole over the set screw to keep it captive.
The idea is to prevent the spindle from turning when the acorn nut is tightened.

Any comments?
1 member likes this
#805638 Apr 17th a 05:25 AM
by TR7RVMan
Hi splash, Good. You are making progress. Light is showing at end of tunnel. Hopefully this will be it.
1 member likes this
#804423 Apr 7th a 06:17 PM
by koan58
The spindles are stopped from spinning by the clamping of the shoulder of the spindle against the rockerbox wall either via the washer (earlier models) or directly (later models). This clamping is all happening at the timing side of things.

With the earlier system with the clamping washer, I have known the spinning spindle syndrome. After much fuss, I found a new washer sorted it.
The spindle is not prevented from spinning by any other part of the assembly, no matter how much you may try loctite in the cap ends.
In the later assembly, where the washer is not between the shaft shoulder and rocker box, the shoulder will embed itself into the rockerbox wall to a degree, and lock that way, YUK.
Though it apparently worked, I'm unhappy with it, and I like the idea (I think from TR7RV Don) to still use a smaller OD washer for clamping, and another washer around it for the rocker spacing.
1 member likes this
#805771 Apr 18th a 07:42 AM
by dave jones
dave jones
Thanks to Koan for the explanation of the spinning spindles. I can't remember the exact way that the washers are fitted in mine but I think they are right for the 67 year 650 model. Anyway, no leaks so there is hope, Splash.

Don's tips were good, too.

The other thing I remember is that I had a bad leak at the spindle ends at the other end from the nuts. I bought the tool for getting the rocker spindle o rings in without shaving them in half but it didn't work . I ended up putting some silicon sealant over the shaved o rings and tapping the spindles back in. A bit of a bodge but it stopped the leaks at that end, luckily.

I wonder if relieving the sharp edges of the spindle holes would stop the o rings being shaved?
1 member likes this
#804864 Apr 11th a 06:00 AM
by TR7RVMan
Hi Splash, I've seen the Tiger motor studs seep, but never leak bad. Generally the gaskets keep oil from running down the head/manifold joint. The oil will more tend to come out by nuts and the exposed threads at end of nuts. However if manifold gaskets are leaking it will leak at gaskets also. You can remove nuts one at a time & put sealant or blue Loctite on washers both sides & nut back side & threads. Wipe squish out off immediately with dry cloth.

Try to determine exactly where leaks are coming from. The tappet block O-rings can/will leak also if they were scuffed or torn during assembly. Push rod tube seals are prone to leaking also. Did you smooth/deburr all the surfaces, all the above O-rings slide past or rest on?

On the last several jobs I've been putting a thin smear of silicon sealant on PRT O-rings. Install & torque head quickly as practical. Has very greatly reduced leaks & kept tubes leak free much longer.

It is basically impossible to correct PRT seal leaks without removing head.

Very hard to tell tappet block leaks from bottom PRT seal leaks. One way is if it leaks really, really bad like a cup per 1/2 mile, it's more often tappet block ring is torn. For top tube leaks, you can stuff rags behind PRT & road test. Rags soak oil from top. If rags are dry, top is not leaking. New clean oil can be very hard to see. Leak test dye & special flashlight & glasses work really well, but take some practice.

If leaks aren't too bad, might be a plan to stuff rags around lower PRT & road test a while to make sure all else is well.

1 member likes this
#806059 Apr 20th a 09:01 PM
by TR7RVMan
Hi Splash, The thread is 5/16-24. Ace by me has the studs but had to cut tank end short. If tank end is too long it can poke hole in tank and/or pull bushing off tank.

The bushing in tank is sheet metal and rather fragile. Blue Loctite 242 or 243 is what I use.

Be mindful of tension of rubbers. Don’t over compress them.
I like to grease threads for steel lock nuts. Otherwise they can grip too tight & unscrew stud, even though it’s blue Loctited.
1 member likes this
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