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:
View attachment 509570
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.