Topic: Yet another F2 Top End overhaul... Where do the o-rings/restricters go ?

[pdeg]

Guys .

Freshening up me F2.  New valves, guides, seals etc etc.  New pistons, rings and gasket set.

Problem.  Been reading the manual and trawling this site trying to work out what goes where 

Particularly where the dowels, o-rings and oil restricters go.  Apparently the F2 is slightly different to the rest of the models.

From memory .. when I pulled it down .. there was some "teepee" shaped seals at the bottom
of the barrels ?  I suspect the head guy pulled the oil restrictors out too.
The dome nuts ?

Do not want to go "downstairs" .. but was thinking that I would pull the bottom off the sump
and blow compress air up the oil gallery to make sure the oil passages are clear ?

Any help would be greatly appreciated.

Cheers
Peter

[flybox1]

I left the dowel orings out,  They really arent necessary

red arrows - oil jets




check out brandEns 'leak free' top end build.
excellent info here  http://forums.sohc4.net/index.php?topic=107040.0

[70CB750]

For the air blow you could just unplug the oil galley - the plug is on the right side, you can't miss it.  Thats where people put oil pressure gauge.  If you unscrew that plug and blow air in it will show you the passage for the oil to the head - which are the two studs in the middle on the back of the block.

You will need o-rings there. 

Dome nut on the head - used with copper washers - seal the stud holes exposed to the atmosphere.  That's one of the problems of F3, 4 studs are accessible through the ribs of the head and it makes them rust.  Easy to spot which, they are rusty.

Not sure what you mean by oil restrictor.

[madmtnmotors]

Particularly where the dowels, o-rings and oil restricters go.  Apparently the F2 is slightly different to the rest of the models.

First of all, check out "brandEn's leak free top end thread":

http://forums.sohc4.net/index.php?topic=107040.0

From memory .. when I pulled it down .. there was some "teepee" shaped seals at the bottom
of the barrels ?

The recess in the bottom of the barrels presses them into a "teepee" shape. They are fat little O-rings that are no longer made for the 750 Honda, but they are still used in other Honda engines. They are necessary and you will need four:

http://forums.sohc4.net/index.php?topic=113672.msg1300721#msg1300721

 I suspect the head guy pulled the oil restrictors out too.

Ouch! These are discontinued... if you can't find them you will have to source used ones. You will need two.

The dome nuts ?

Again, check out "brandEn's leak free top end thread":

http://forums.sohc4.net/index.php?topic=107040.0

The "dome nuts" also use copper washers.

[pdeg]

Tx for the quick replies guys .... and that link to the other thread was excellent.   Great snaps.
Will trot down and get a steel rule to check for warps 

Got my gasket kit  from Cycle X... so hopefully all of the gaskets are there... even the
unobtainable ones 

Interesting that you do mention using some gasket sealer...  Cycle X said that their gaskets
do not need any .. but their web site mentions it.....  Given that the wretched thing
is such a pain to get too..... am tempted...

Gave gone for the Cycle X  MLS (multi layer steel) head gasket... no re-torque required.. apparently.

Great advice on the oil gallery access... tx.

Am still toiling away with the scotch pad and cleaner... so have not unpacked the stuff yet.

And had to use sandpaper on the studs...    Have not upgraded them.  Too scared to get the
old ones out....

Will keep in touch.

Tx again.

Peter

[flybox1]

HD studs are a good upgrade.
Tricks to getting the old studs out?  double nut.  penetrating oil(atf/acetone, or pb blaster)  heat gun, and a few whacks from a BFH.  some will come out right away.  others you may have to persuade for a day or 3.   

[70CB750]

I am with you on studs, I tried to get one out and since it did not work, I figured they are strong enough

What I did for rusty studs - the 4 exposed - I smeared them in vacuum grease and covered the length with shrink tubing.  With cylinders in place I used some hondabond to block the water from entering the stud hole; the idea is that water will not get lower than the head gasket level.  If it will work, I don't know.  That's for the next owner to call me names for 

[pdeg]

Tx guys... all good advice...

A small point .. the picture at the top of this thread shows the acorn nuts inside the cover.
But the link shows them across the front 4 studs.... as does the text.  Will go with that I think.

Regarding the oil constrictures..  The head guy gave them back in a plastic bag 

I put them in for a trial fit... and they do not seem that tight.  Do they just sit there
and are retained by the valve gear ?  They seem to gave a spear type thingy on the bottom.
Is this significant ?

Managed to get the oil gallery plug off the side. when I went for a 6 corner socket.. as
it was a bit "flogged out".. Sigh ... the joys of a pre-molested motorcycle 

And more annoyingly .. is seems that of the 2 oil feed studs... one of them has some
marks where the O ring sits... Sigh.. Goop in coming into my life.  And sadly the stuff you
guys talk about has different names in Aussie 

I must learn how to put images in-line ... attached.

Cheers
Peter

[flybox1]

You can certainly put the acorn nuts where you want, but they are intended to be used in conjunction with a  copper crush washer to seal the 'open' studs to prevent head leaks.
The four studs, adjacent to the oil feed and return studs/passages are open to the elements. You know the ones.... They have the tiny cone shaped orings under the cylinders you mentioned earlier.....the acorn nuts go on top of these studs.
Go back and look at the cylinder head fiche.  Parts #15 & #4

[pdeg]

Tx for the reply ...appreciate the trouble.

And I am sorry to be a bit dense....

But it seems that the 4 studs open to the air are the ones across the front of the motor.
An annotated picture attached.

But you have also made me re-examine what I "thought" was the oil feed system.
In particular... what I thought was oil feed to the rockers may atually be oil "jets"

These were the came out of the head when it was refurbished.. and they do not seem to
be a tight fit into the head.  Is this a concern ?

Tx again

[madmtnmotors]

But it seems that the 4 studs open to the air are the ones across the front of the motor.

LOL... the four studs across the front, as indicated in the picture, only expose their nuts to the atmosphere. There are four other studs that are actually exposed to the atmosphere where they pass through the head...

and none of them have their nuts exposed to the atmosphere (I hate it when that happens!  )

Like flybox said, the acorn nuts/copper washers go on the studs with the extra ("cone shaped") 5.5x3 o-ring at their base.


See how I was able to pull the string out from between the fins in the head?



This is one of the four locations where the acorn nut would be used.

[70CB750]

Take your time, man, it will all make sense in the end.

[pdeg]

Ah

Now I understand... tx for the photo.. it all makes sense now.

Talking about dense... what were they think when they decided to do that.
It never occured to me that somebody would even contemplate doing something like that,
especially just for a few studs.  And the ones on the front ?  So the water can get it in
easily.


They have basically made a water bottle...  Fortunately we do not get much rain here, but
I wash the motor with a pressure sprayer...

Sounds like a stud replacement is a matter of course on the next go at this....

Tx again guys .... Still scrubbing washing .... trying to clean parts... Joy.

We keep this up for the next poor slob.

Cheers
Peter

PS .. the link to O rings in madmtnmotors  signature was also illuminating.  Have not checked the gasket kit yet....

[madmtnmotors]

PS .. the link to O rings in madmtnmotors  signature was also illuminating.  Have not checked the gasket kit yet....

As far as I know there aren't any gasket sets that include the 5.5x3mm o-rings. They must be purchased separately.

[flybox1]

PS .. the link to O rings in madmtnmotors  signature was also illuminating.  Have not checked the gasket kit yet....

As far as I know there aren't any gasket sets that include the 5.5x3mm o-rings. They must be purchased separately.

Correct.  They are not in any kit.  They are to be used with the oem studs.
If the OP uses HD stud, these orings are too small. 

[pdeg]

Ahh ... worked out how to share images in-line ... handy too.. just use the google+ share stuff.  Have they
installed a mod to make it easier ??.. A cut and paste would be really nice...

Part 1 of the Cycle X gasket set.

Notice the "fat" little ones. second row from the bottom. I presume these are for the studs.  is 4 enough ?
I am using OEM studs.    It would be REALLY handy if somebody could give me  hint as to where the rest go.
Suspect that there are some spares.  OR they for the bottom end.  As it looks like I have the seals for the bottom end as well.

Cannot say I am an expert in gaskets ... but these Cycle X ones feel really nice.. and the rubber stuff feels
like it will seal well.



Part 2


And this is REALLY going to upset the purists .. But I have replaced the cam chain with a new "heavy duty" one  with a link. 

[flybox1]

If have a caliper, this may help a little.

[madmtnmotors]

Notice the "fat" little ones. second row from the bottom. I presume these are for the studs.

I do not believe so. The I.D. looks too large. The correct one will have an I.D. of 5.5mm and be 3mm thick. The CycleX kit I used did not have the 5.5x3 O-rings.

And yes, four are required.

[flybox1]

the FAT little ones might be the oil jet o-rings for under the cam towers.

[pdeg]

Mmmm .... have a vernier.  One of tools you buy on a whim and, after a while, wonder how you
ever lived without 

Anyway.. .I suspect these are the ones.



and




Having trouble comparing with the parts list in a previous post 

The only ones there that seem to be the  right ones , are 5.8 x 1.9.

Fairly relaxed about the ID but not the thickness.

Mine are 5.5x2.5 mm

I am thinking "suck it and see"   

[madmtnmotors]

Actually, those look like they would be the ones you need after all. I guess CycleX has started to include them?

[70CB750]

Actually, those look like they would be the ones you need after all. I guess CycleX has started to include them?

I would think so, I rebuilt the head on F3 with their set.

Unless of course I did not use them at all  - we shall see

[pdeg]

Looks like mine.  Is that the MLS head gasket ?

[70CB750]

Yes.

[pdeg]

Might as well keep on going... for the sake for completeness... Never know .. may help somebody. Or not.
Chime in anytime

Sump off.  It seems that there was not too much rubbish in the screen



These $5 pliers are actually handy for putting the rings on .. Do not work well for the oil scrapers ... and I did not
realise that you have to put the spacer in first, as it gets held in by the rings.  I could not find any markings on the
scraper rings.. so I presume that does not matter which way up they go.



Pistons on the rods.  These must be the last F2 pistons in  captivity. Got them from csmnl 



Cleaning up the top of the barrels.   400 grit sandpaper on a file..  I presume that the dark bits are the low spots.
Can see the  work of the bloke that had it to bits previously    Any thoughts on this idea ?  For all of the hassle
should have asked the bike shop to clean and face this part..



Now to find some bits of wood to prop up the pistons so I can get the barrels on. Not looking forward to this
part...  Hoping I can get the rings in with me fingers..  Looked at the hose clamp option .. but the adjuster
would get in the way ?  Steady does it..