This Forum is now CLOSED use the link to get more details viewtopic.php?f=3&t=13924#p102587
#96441
Sorry bit long winded...................

Exasperated, 500 AVL I have completely stripped, checked over and rebuilt the engine , it had a hone and new piston as some damage was evident and I fitted a crankcase gasket as it was missing and stuck together with goo. I have also removed the entire EURO 4 system (including catch can), opened up the cast stub by the engine number and run a breather pipe along the chain guard. The original oil tank breather now runs from the top of the oil tank and is plugged into the stub on the air filter box (still have CV carb with air filter) as looks tidy and follows original logic.

Very careful about oil level and kept low on dip stick

So finally all ready and started without issue (sounds good) had a short shake down ride round village, all seemed ok and checked oil level when I got back, needed another 150ml to bring back to low on dip stick . The back brake was binding so stripped the wheel and fitted new shoes (old ones were a right mess!) . Oil tight at this point.

Today took it out today for a back brake test and adjust and stopped after a couple of miles to check the brake was ok and not too tight. To my horror there was oil running off everything around the back of the gearbox, swinging arm and the plastic mudguard section, made a nice pool of fresh oil and a right mess of my bike!! :-( . Checked the oil level and is just on bottom of dip stick.

Too add insult to injury ran out of petrol as forgot I had only stuck a few litres in for a test start and had to push it last mile (near death experience in the sun!)

Just been cleaning it up and the only logical place the oil has come from is out of the oil tank via the breather and into the air box, filling it to a certain point until the level coincides with a hole that allows the oil to drip onto the plastic mudguard section and the rear of the gearbox, inside of filter box is covered in new oil) . I could be wrong but stripped it all and is very oily in that region.

So, what can cause the oil tank to over pressurise as it just has to be the fault, it did it before I stripped it and seems to be still doing it, maybe I put too much oil in it but didn't go over half way up the dip stick but was carful not to.

I feel like I am missing something here and any thoughts would be appreciated!

TIA
#96446
To be honest I didn't yet as was just first start up and run but did only put in 1.5 ltrs as you advised. I did charge the big end before putting the timing cover on and also applied a good squirt of oil everywhere when assembling so could easily have used another 1/2 ltr I guess.

What I was trying to get to the bottom of is why this engine seems to need almost a ltr less than it should or it just chucks it out the breather, putting the manufacturers recommended amount in should be ok and not result in a right mess like this, I just can't figure out what the problem is and what is causing it!
#96447
+1 on the overfilling business, for a while my old Electra-X just had a short 90° length of hose coming off the oil tank vent with a duck-bill at the end pointed at the gearbox sprocket to try and replicate the old Redditch Bullet system (airbox long gone by then), but it was very vulnerable to over-filling and/or spirited riding and would happily spray oil all over the back of the bike. It was after that when I replaced the duck-bill with a proper non-return valve and the long pipe to the back of the rear chainguard.

You might find that with the oil control rings on the new piston still being run in, they won't do their job properly until this is finished, until then there could be a bit of oil getting past them, or the oil rings on this piston could just be poor, even if the compression rings are still doing their job OK.

It was Euro 2 regs for the Electra-X, not Euro 4.

So you have the old-style breather stub on the left-hand side of the engine now opened up, what size drill were you able to use? Presumably you were able to drill right through into breather passageway behind the stub? Is this new hole now breathing freely?

What you could do is to run the breather pipe from the opened-up stub via a non-return valve back INTO the oil tank via the outlet at the top of the tank, then use one of out hosts' oil filler neck extensions, and use both of the pipe stubs running off THAT for breather exit pipes. That way the oil tank also acts as the catch can, with excess oil being put straight back where it belongs, while having a higher take-off point for the relocated breather pipes will give you a little more protection against overfilling.

A.
#96455
Hi Adrian, yes sorry EURO 2 forgot how old it is! :-)

I do see merit it what you suggest and will explore it, does ay on the website it is not suitable for the AVL 500 but sure only needs a tweak to make fit?

I drilled a 5mm hole, as as big as I dare, the outside casting is very rough and breakthrough was always a possibility!!

Just started it up and yes it is blasting out of the opened up crankcase breather, which of course was the logic of doing it to relieve some of the pressure going into the oil tank via the OEM crankcase drilled hole, so seems to have worked, no oil coming out of it (still clean) and a good pulsed air blast.

While running I pulled the breather pipe off the top of the oil tank to see what was going on there. Again a real blast of air but this time blobs of oil blowing out with it (thar she blows!) Interesting as the oil level is way below this so there must be some serious turbulence being created even on tick over to have the oil surface boiling up to come out of the top hole, must be over 100mm away to the top of the oil. Bearing in mind that the OEM crankcase drilling is high and well above the oil. Can see how on a run the build up of oil is forced up the pipe and into the air box, not great as it is leaking out of the spigot left over for removal of the PAV system and being forced by the wind basically everywhere! :-( and also back into the engine and through the carb, there is white smoke as the result.

Understand the logic of the Hitchcock kit but it will put all the pressure from the crankcase breather back into the oil tank, I was trying to reduce it to prevent the oil being blasted out. I think with the engine running the oil will never run back and will always be pushed out, I wonder if there is a breather valve design on another bike/car engine that could be employed here and screwed into the top of the oil tank?

Anyway will use Papasmurfs dipstick in the meantime and keep the level low, about 20mm below the end of the dipstick I think is about right as guess this level beats the turbulence and the oil falls back into the tank. Also need to rethink the pipes as can't have all that oil wrecking the air filter and going into the carb, clearly not good!!

Trick has to be reducing the turbulence in the tank, it comes from the OEM drilled hole, maybe it is not in the best place? Or maybe they printed the manual wrongly and I am putting too much oil in! :-)
#96457
Allanfox wrote:
Fri Apr 23, 2021 10:47 am
Or maybe they printed the manual wrongly and I am putting too much oil in! :-)
The 2.25 litres is the first fill for a new engine or after an engine rebuild.
The nooks and crannies in the engine and cylinder head hold about 700cc which does not drain out at an oil change.
That is why I made the dipstick, which is for use on a cold engine. 1.3 litres at an oil change is sufficient.
There been a mass of comment on the forum about over filling Electra Xs.
#96459
Don't forget that with the engine running you're going to be getting oil pouring back into the oil tank from the timing chest. The blast from the internal breather hole could be catching this. Note that the Redditch Bullets also had an internal breather hole between the crankcase and the oil tank, actually in the joint face just below the flange for the cylinder.

I'm working on a spare set of Electra-X crankcases on and off at the moment and these didn't have the breather stub at all. What I have done is mill/finger file a flat where it would have been, and I shall drill and tap that ¼" BSP, for which any number of hose fittings are available for some decent breather plumbing.

The reason the Hitchcocks' filler extension breather kit is not sold for the Electra-X is because it relies on the older models' left-hand crankcase side breather vent, but yours now has this! If you connect this up as I describe you will still have TWO breather vents coming off it, or you can plumb it in as on the earlier models so that you have one breather pipe still coming out of it, as well as the breather pipe coming off the top of the oil tank.

On the standard Electra-X there is a hose tail fitting screwed into the top of the tank for the 10mm breather pipe, I have never been able to work out quite what thread it uses, but it's pretty close to ¼" BSP, which will screw in with a bit of thread sealant.

Non-return valves don't need to be vehicle specific, generic ones come with stub ends for fitting straight into bits of hose, or threaded for the fittings of your choice , e.g .

Image

Image

A.

Shop for accessories at Hitchcocks Motorcycles