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Discussion Starter · #1 ·
Hi all I have recently rebuilt my (69 TR6) engine, when I mounted the head both upper pushrod tube (castellated top type) o-rings were damaged. I now have the head off and new o-rings.

I have read Haynes and the Triumph manual, but stuffed it up somewhere on the way
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Any clues, on a better result, wife is a little concerned with the oil issues and it's costing me a fortune in degreaser.

The motor is running beautifully with the 7.5:1 pistons & even idles very smoothly:):)

cheers Mal
 

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I`ve found that installing the tubes into the head first is good.
A little grease on the O-rings and push the tubes in hard.
Then manoeuvre the assembly onto the engine.
 

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Discussion Starter · #4 ·
Make sure you use the correct lower silicone rings with the square profile. Maybe you used one size too thick?
Hi Caulky & Paul

Yes that's whats appears to have happened, the new lower o-rings were about half the height of the ones I used first up.

The head went on again today, with no leaks:):):) I also lightly rounded off the upper lip where the o-ring seats in the head, as per the Triumph manual.

I have a few tidy up jobs tomorrow & hopefully I'll give it a decent ride later tomorrow morning. On Sat mornings the old bike mob meet for coffee at Moruya near here; that is the immediate goal. The long term goal is the "kick start rally" weekend in two weeks.

Also two people putting on the head makes it easier, one can check the line up of the tubes as the other lowers the head

cheers

Mal
 

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Hi Caulky & Paul

Yes that's whats appears to have happened, the new lower o-rings were about half the height of the ones I used first up.

The head went on again today, with no leaks:):):) I also lightly rounded off the upper lip where the o-ring seats in the head, as per the Triumph manual.

I have a few tidy up jobs tomorrow & hopefully I'll give it a decent ride later tomorrow morning. On Sat mornings the old bike mob meet for coffee at Moruya near here; that is the immediate goal. The long term goal is the "kick start rally" weekend in two weeks.

Also two people putting on the head makes it easier, one can check the line up of the tubes as the other lowers the head

cheers

Mal
You be careful here Mal, its not a case of any old thickness will do. Too thin, oil leaks, too thick, warped heads. You really need to calculate the space you have and select a thickness that best suits. Aim for .030"-.040" crush. RR
 

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Discussion Starter · #6 ·
You be careful here Mal, its not a case of any old thickness will do. Too thin, oil leaks, too thick, warped heads. You really need to calculate the space you have and select a thickness that best suits. Aim for .030"-.040" crush. RR
Retro, yeah we appear to have it right (this time) we feeler gauged the squish @ .030" this time, which seems right. In the two manuals (Haynes 63-83 & Triumph 63-70) I have there seems to be no mention of how much the the push rod tube o-rings should compress on reconstruction.

cheers

Mal
 

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Discussion Starter · #8 ·
I hope your rallye is as fun as ours (just passed).

I humiliated myself in the "cold start" race and three-kicked my race bike; last off the line on a slow shameful pass.
Hi Paul, Murphys Law in full swing, I'll post a report on our rally.

The bike & I made it to coffee this morning, at a very leisurely pace. There are now only a couple of minor leaks, it now has 23 miles on its new speedo.

Its running & idling very smoothly, and while I didn't get much over 3000 revs the performance doesn't seemed to have suffered too much with the low comp pistons.

I'll have another tweak with it this week.

Cheers

Mal
 
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