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Discussion Starter · #1 ·
While refitting the exhaust rocker box, again, I noticed that there`s a gap between the inside of the case and the cylinder head socket bolt.
In the `72 T120 spares book, there`s a spacer 71-2598.
On some of the suppliers sites, its described as `washer thick`.
These are missing from my engine, and have never been fitted, as far as I know, which maybe explains the mis-alignment between the rocker box holes and the bolt holes. (Distorted rocker box?) These are absent on the T140.
Anyone know the thickness of these spacers?
And why are the bolts so long, 1 1/2" under head? 1" would do.
In fact all of the head/rocker bolts seem to be excessively long, or perhaps its a feature of the 1974 T120V bitsa.
 

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Very observant Caulky!!

I have the rocker boxes off my '72 at the moment and pounds to peanuts the spacer was not installed on this bike either.

I'll have to scurry down to the shed tomorrow and investigate this bit of intelligence.

Thank you. RR
 

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Missing spacers

Caulky, my '74 T120V doesn't have the spacers either (and never did). Everything aligns nicely on mine without them, so I think it may just be that your rocker-box is warped rather than the absence of spacers. If the spacers aren't part of the T140 set-up, then it is highly likely that the '74 T120's never ever had them either.

I may be wrong (in not having ever had a T140 to compare to), but I think the only differences between the '74 T120 and T140 are the crank, rods, pistons, barrels and head (and the side badges!).
Mark
 

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Sounds like a messed up rocker box. If the holes are misaligned and there is a gap upon fitting, that's not right at all.

There are a dozen different rockerboxes between all the various pre-unit, unit, 500, 650 & 750 engines; you could easily have an incorrect part.
 

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Sounds like a messed up rocker box. If the holes are misaligned and there is a gap upon fitting, that's not right at all.

There are a dozen different rockerboxes between all the various pre-unit, unit, 500, 650 & 750 engines; you could easily have an incorrect part.
Im with you 100% GPZ,on this one.Ive been through this myself once.
 

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Hi Caulky,

Followed up on that info you provided and find that I could not fit a spacer under the rocker cover.

Interesting though is how does the cover seal itself against an oil leak through the bolt hole?.

Perhaps it's faced well enough (metal to metal) to seal?
Not enough oil in the rocker box to cause a leak that high up?

Modern engines would have had a rubber grommet seal on a setup like this I would think.

The rocker bolt holes on my bike have a residue of "stuff" that could have been a sealer at one time. I wonder if the PO had a small oil weep from these bolt holes?. RR
 

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Discussion Starter · #8 ·
I think the spacers are supposed to just fill the space...about 1/16th".
The T140`s must be different.
I`ve found a supplier for the boxes 71-2570, unfortunately I think the rocker assembly would need to be rebuilt.
This is probably tempting fate, but I`ve never been troubled by oil leaks from the rocker boxes.
I did have leaky tubes once, but fitting the correct seals cured it.
 
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