B18 Con rod bolts


Boyle

Boyle

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Would someone be able to tell me what tourque setting the con rod bolts need to be set too on a B18C6

Thank you
 
They need to be measured with a rod bolt stretch gauge when tightening.

0.13-0.15mm .
 
Darragh_K said:
They need to be measured with a rod bolt stretch gauge when tightening.

0.13-0.15mm .
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I started doing them that way but it doesn't seem to do them up very tight at all
 
Boyle said:
I started doing them that way but it doesn't seem to do them up very tight at all
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May seem that way , but for instance the SiR B18c rod bolts are ~45nm .

This is pretty crucial for keeping a good clearance at high rpm !
 
When we were measuring the bolt and doing it that way they were only getting tourqued to about 20nm

You think I should just go with the 45nm from the SIR then?
 
Rich777 said:
How was you measuring the stretch?
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I was unable to get a connecting rod bolt gauge but after talking to Type-R-Dunx he said that he used a vernier gauge.

He measured the bolt in place first the tightend untill between 0.13-0.15
 
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That a very inaccurate way of measuring the stretch. Try a decent micrometer and see if you get any better luck. I have a modified screw Mic that work's well that I use to check the free lengths with.
 
We have used a micrometer. They just seem really lose, or are they meant to be like that. We are doing them up finger tight and then its about half a turn on a ratchet. Does that seem about right????

It was only doing them up to around 20nm
 
I just spoke with Honda technical and they said that if its an M8 bolt its 20nm + 90 degrees, or and M9 its 30nm + 90
 
Boyle said:
I just spoke with Honda technical and they said that if its an M8 bolt its 20nm + 90 degrees, or and M9 its 30nm + 90
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Did they say that was for the B18c6 ? Roughly sounds right ... but if I was you Id try around again for a stretch gauge
 
If its not a race car motor do it to factory specs, hell you not revving to 10,000 plus rpm so dont complicate things. Think how many miles that stock engine did on factory torques settings without letting a rod bolt go.
 
rs250nut said:
If its not a race car motor do it to factory specs, hell you not revving to 10,000 plus rpm so dont complicate things. Think how many miles that stock engine did on factory torques settings without letting a rod bolt go.
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I agree with you 100%, it's only that in the Honda workshop manual it says to measure the stretch of the bolt rather than a specific tourque setting.

I have now done my bolts to 30nm + 90 degreese
 
I was looking at the b18c4 rod bolts torque settings which is 33ft lbs in the manual
 
rs250nut said:
If its not a race car motor do it to factory specs, hell you not revving to 10,000 plus rpm so dont complicate things. Think how many miles that stock engine did on factory torques settings without letting a rod bolt go.
Click to expand...

The rod bolts are stretch measured from the factory , this is why the rod bearings last so long....
 
It's more to ensure the cap's are torqued up correctly more than anything.
 
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