1969 Triumph Bonneville

[RichardM]

Valve guides Ok?

 

[Rannsachair]

Valve guides Ok?

I will check at the weekend - hope not, they have not done many miles. The valves/seats are good - did a paraffin leak test.

 

[OJCar]

View attachment 509569

In section:
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Standard seal/gasket set:
View attachment 509571

Thank you, I can see them being useful on C15 push rod tubes in the near future!

I will be looking for a good second hand one,

Newness has worn off that one for sure!

 

[8ob]

Looks like it’s running a tad rich on the near side pot. Always been a bit of a pain keeping oil in British bikes, never understood why they run with two pistons going up and down at the same time, it’s a windage nightmare.

Bob

 

[Rannsachair]

Looks like it’s running a tad rich on the near side pot. Always been a bit of a pain keeping oil in British bikes, never understood why they run with two pistons going up and down at the same time, it’s a windage nightmare.

Bob

The inlet manifold threads into the head with a large locknut, it had come loose - so easy fix.

 

[Rannsachair]

I may be best doing another post for advice on this:

two rocker box mounting threads (1/4 - 20 UNC) have been repaired in the past. the thread inserts are not helicoils and partly unscrew every time I take them off!

I have tried cutting a slot in them to screw them in and it worked at the previous rebuild, this time they would not screw in so I broke of the top thread with a chisel punch and cleaned up the face as best I could.

So I could reassemble as is and expect them to come out again next strip down, or what are my 0ptions:
1. Try loctite on them, leave to set before fitting - would it help or will heat destroy the loctite anyway?
2. Try and get them fully out, measure od thread and try making a new insert with a slot?
3. look for an alternative like a time sert and see if there is enough material to redrill and tap?

 

[Seadog]

Drill them out, fill with Belzona, or equivalent. Then drill and tap

 

[Robotstar5]

A few centre pops round the perimeter to lock them in?

 

[8ob]

Needs to be a good thread, it’s not just a rocker cover, it also anchors down the rocker shaft. Inserts/helicoils would be my preference, if what’s there has gone squiffy maybe go for a turned up special.

Bob

 

[Rannsachair]

A few centre pops round the perimeter to lock them in?

I like that, simple

Needs to be a good thread, it’s not just a rocker cover, it also anchors down the rocker shaft. Inserts/helicoils would be my preference, if what’s there has gone squiffy maybe go for a turned up special.

Bob

The main head bolts do most of the work, the centre two:

The torque setting on the 1/4 outer ones is just 5 ft-lbs.

 

[Rannsachair]

Doing the fun job of giving the valves a quick grind:

 

[Rannsachair]

Was chatting with my dad who was reminiscing grinding in valves on buses and lorries and having his journeyman check them all and getting him to redo the slightest imperfection 0 - was not his favourite job.

Valves back in, I use a cut piece of conduit to space out the spring compressor

sacrificial cable ties are handy for retaining collets during assembly:

Will be greasing the head gasket and seals for assembly tomorrow.

 

[Armin]

Ich verfasse am besten einen weiteren Beitrag mit Ratschlägen dazu:

Zwei Befestigungsgewinde (1/4 - 20 UNC) des Kipphebelgehäuses wurden in der Vergangenheit repariert. Die Gewindeeinsätze sind keine Helicoils und lösen sich jedes Mal teilweise, wenn ich sie abnehme!

Ich habe versucht, einen Schlitz hineinzuschneiden, um sie einzuschrauben, und beim letzten Umbau hat es funktioniert. Dieses Mal ließen sie sich nicht einschrauben, also habe ich das obere Gewinde mit einem Meißeldorn abgebrochen und die Oberfläche so gut wie möglich gereinigt.
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Ich könnte sie also so wieder zusammenbauen und erwarten, dass sie beim nächsten Zerlegen wieder herauskommen, oder was sind meine Optionen:
1. Versuchen Sie es mit Loctite und lassen Sie es vor dem Einbau trocknen. Würde das helfen oder würde die Hitze das Loctite trotzdem zerstören?
2. Versuchen Sie, sie vollständig herauszubekommen, messen Sie das Außengewinde und versuchen Sie, einen neuen Einsatz mit einem Schlitz herzustellen?
3. Suchen Sie nach einer Alternative wie einem Zeitmesser und prüfen Sie, ob genügend Material zum erneuten Bohren und Gewindeschneiden vorhanden ist.

Verwenden Sie Time Sert Gewindehülsen, die bündig mit der Oberfläche abschließen und fest in das Material eingepresst werden.

 

[OJCar]

 

[Rannsachair]

Verwenden Sie Time Sert Gewindehülsen, die bündig mit der Oberfläche abschließen und fest in das Material eingepresst werden.

Yes they may be timeserts or similar.