3B precup question.

Darkwing58

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I have the head for my 3B at the machine shop. We have a question about the instal of the Precups.

in the attached picture you can see one of the cups. It appears to have 2 pins installed on the side of it.
the pins are one at the top of the picture inside the gasket ring and one at the bottom right where the casket runs.
is this normal? All pre cups are installed the same way.


thanks for your help in this matter.


84388C54-AC3F-40F6-A8B7-BD27D3819982.jpeg
 
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Joined
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No, not OEM.
Only the small one should be present.
The two other have been installed in a machine shop to secure the precups in place. Likely they tried to machine the surface and the cups were a little loose.
Since the hole are made, I think you need redo the same or the head must be weld to fill these hole.
Interesting to see that even if the pin are inside the combustion chamber they stay in place.

One shop did the same on my cyl. Head without warning me first…they installed a similar pin almost in the middle of the combustion chamber :( after I complain, they said they do that all time and it never fall (pin)
 
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Thanks for posting this, really interesting. I have looked at a few different head repairs and skimming. It would have taken some skill to have done this, imo. Not all shops would take it on and just say buy a new head.

Ome it is not for sure, but a determined effort to hold the precups. The pins, would have come from the experience of precup failure and then doing something about it. It certainly looks like it worked.

It would boil down to the hourly rate of the machine shop vs new head cost.

Not sure if you can get new cast 3b heads, but only chinese 2h heads are available..
 

Darkwing58

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Location
Bethel Minnesota
Thanks for posting this, really interesting. I have looked at a few different head repairs and skimming. It would have taken some skill to have done this, imo. Not all shops would take it on and just say buy a new head.

Ome it is not for sure, but a determined effort to hold the precups. The pins, would have come from the experience of precup failure and then doing something about it. It certainly looks like it worked.

It would boil down to the hourly rate of the machine shop vs new head cost.

Not sure if you can get new cast 3b heads, but only chinese 2h heads are available..
Try these people, never dealt with them

 
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Try these people, never dealt with them

Thanks man, shipping from the US to Oz is usually out my budget.
 

Darkwing58

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Thanks man, shipping from the US to Oz is usually out my budget.
No worries,
so how’s Melbourne these days. Spent a year there as a crewman for a blimp, advert Whitman’s Chocolate In 1992- 1993.

what a great place Australia. Loved the meat pies!
 
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No worries,
so how’s Melbourne these days. Spent a year there as a crewman for a blimp, advert Whitman’s Chocolate In 1992- 1993.

what a great place Australia. Loved the meat pies!
I think that was collingwood, chapel st area...

Well, I can say it use to better. 90's was a great time, how I met my wife , at punters club, brunswick street, 3x free bands everynight, 20cents pool and $1 pots of beer. Live music scene was excellent.

We had 2 years lock down, no travel over 5km. Most lock downed city in the world Damaged the psyche, especially the kids. But when I look at Phillipines the kids got a typhoon just after 2 years lockdown.
I think it will come back, eventually.

Can't really say what was the wrong or right thing to do, it would suck to be a politician now more than ever, choice of sh#t or even more sh#t!

I get dismayed with the push for green wash. Sure pollute less, but for pity sake make it last long, not throw away cr@p. It shall take someone like Napolean or Hitler probably, make a vw bettle, cheap, reliable, fixable, economical, last a long time..folks wagon, law.

Folks will be forced to go nuclear to supply that much electricity imo. GDP economics includes rubbish. I watch the loggers clearing mountains to build throw away shoe box houses.

Sorry, Rant.. hopefully lead by example, fix something old and good. Reason why we like cruisers.
 
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I think that was collingwood, chapel st area...

Well, I can say it use to better. 90's was a great time, how I met my wife , at punters club, brunswick street, 3x free bands everynight, 20cents pool and $1 pots of beer. Live music scene was excellent.

We had 2 years lock down, no travel over 5km. Most lock downed city in the world Damaged the psyche, especially the kids. But when I look at Phillipines the kids got a typhoon just after 2 years lockdown.
I think it will come back, eventually.

Can't really say what was the wrong or right thing to do, it would suck to be a politician now more than ever, choice of sh#t or even more sh#t!

I get dismayed with the push for green wash. Sure pollute less, but for pity sake make it last long, not throw away cr@p. It shall take someone like Napolean or Hitler probably, make a vw bettle, cheap, reliable, fixable, economical, last a long time..folks wagon, law.

Folks will be forced to go nuclear to supply that much electricity imo. GDP economics includes rubbish. I watch the loggers clearing mountains to build throw away shoe box houses.

Sorry, Rant.. hopefully lead by example, fix something old and good. Reason why we like cruisers.
but Australia is still a great place for now!
 

Darkwing58

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but Australia is still a great place for now!
Well I keep track of the Australian politics thru a few friends, sad to see the government so out of touch with the average Australia.

and yes it a great place to wonder around.
 
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There is few places in the world where I can buy and love 100 acres of rain forest with 400 year old trees, which is cheaper in yearly rates than keeping a car registered.

Dumb lucky.
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