G2 CRANKCASE BREATHER

[dodger]

I am in the throws of restoring several boxes of junk that were sold to me as an alleged 1959 G2 that was up and running in the 1970's, he must have dreamt it.
However, the crankcase breather tube is missing and I need to make a new one, the only dimension I am struggling with is the diameter of the central bore, it is part number 042221.
If any one has an example that they could measure and let me know the bore I would be most grateful.

Laurie

[cbranni]

Without looking 5mm dia hole would be about right, but it is guess, again there are a few different breathers depending on year.

Colin

[Ozmadman]

Can of worms!! 3 types of breather/stator set up... early one as yours probably is... breather tube threaded to screw into the casing and a tight push fit into the stator which is sandwiched between the two crank bearings , shouldn't think the internal bore is that important but the external bore must be exact as it must be a tight fit in the stator. Also, is the engine stripped as the hole in my stator which accepts the tube was worn oval allowing the stator to rattle around. Type two, which can be a replacement for type one, tube threaded at the lower end to thread into a thread hole in the stator (lot better idea) Type 3, and not interchangeable with other types, no tube at all just a hole in the casing and a bolt threaded into the casing to hold the stator. All parts for type one and two are available so no need to make anything. see pic of my knackered stator and tube and the later type two

[dodger]

Breather.jpg

Thanks Colin and Paul, you are right in that my breather is the earliest type, and as you can see from the photo the hole in my stator is well worn as well and has a stepped orifice.
I have drilled the hole in the breather tube to mimic the smaller diameter, but that is just a guess it may be larger in the real part, hence my question.
The club spares scheme do not stock either part so where have you seen these parts available?

Laurie

[Ozmadman]

Here is an excerpt from the workshop manual.

"On engines with a number before
6850 a rattle can develop which can be mistaken for movement
in the big end assembly. This rattle is due to movement of the
crankcase release valve stator 042220. The noise can be overcome
by removing the release valve tube 042221 (which locates
the stator) and increasing the effective diameter on the end of
the tube by an electrical deposit of either chrome or copper.
The tube should be thus treated over a length of 3/8" from the
tube end. Alternatively the engine can be dismantled to use
a modified tube 044083 and stator 044084. The new stator is
threaded internally with a threaded tube."

If you have gone that far then I would use the later set up (type 2) and use some loctite on the tube thread as you screw it into the stator and don't forget a decent fibre washer under the tube hex head. Do a trial run to make sure the tube does not screw into the stator so far as to protrude into the other side thereby hitting the rotor. What you want is a tight fit with the tube just short of protruding through to make sure it is using as much of the thread in the stator as possible so use fibre washers under the head to adjust this. Also, as the tube screws into the stator and not the casing just ignore the fact that there is the thread in the casing, it will be fine but make sure it is tight and loctited


Check the club for the latest parts or try these 3 http://www.russellmotors.co.uk/ or http://www.amcclassicspares.com/ or
http://www.andrew-engineering.co.uk/

Good luck Paul

[dodger]

Thanks Paul, Andrew Engineering have some of the items you have highlighted with part numbers so will have somewhere to go should my own repairs prove inadequate, thanks for the advice.

Laurie

[rob99]

Evening all just registered for my dad who has a rest going on with the light weight.

He has a short bolt going into the stator thats what it looks like, my dad's asking if the stator rotates or is stationary when the engine is running,

He has removed side casing to get some access to the breather and has seen this extra bolt that he's not sure of, we have read the breather thread on here and hope some one can shed some light I'll try and get some photos on for better identification.

Thanks rob and malls

[Janet]

Rob, welcome to the forum.
The stator fits into the outer cover of the chaincase and is held in place on three studs and nuts. Therefore it cannot rotate. The magnetic rotor spins with the engine.

I see from your profile you are in Hull. So am I. Not that I will be much help to you as I'm usually the person with the tales of woe. I'll see if I can dig out some photos of what the stator should look like insitu.

[rob99]

Hi

Thanks I appreciate that and I'll try and get some pics up from my dad's dilemma of what he has and what it should be as he says he has two engines and there both the same layout with the breather

[Ozmadman]

Are we still talking about the breather stator (on the crank)or the alternator stator? if it is you cannot see it unless the engine is stripped and the casings split