6CTA 450 Intake Manifold bolts

[Doug Patterson]

All you Cummins gurus

I have two bolts bad on a Port Engine . Both are the ones that hold the injector line stanchions . One is stripped out ( got a 8mm x 1.25 heli coil for that ) and one looks to be stripped and broken off inside …..however both had a 8 mm x 25mm bolt just rattling around in the hole .
The real question is ” are the bolts all the same around the intake ? The front most one looks pretty straightforward as far as a fix goes . Just curious about the second one . It looks like a broken off bolt is in the hole OR it was never drilled and tapped about 1.62 deep in the first place .

Any Ideas ?

Topic

[Rob Schepis]

It's Good to be "Capable"

Good for you, sure is nice to be “tool savvy” and be able to do these types of odd fixes.
Bottoming taps are key for blind hole work.
For anyone not familiar, see attached, the bottoming tap has a flat end (not tapered) so the cutting threads run the full surface (for full depth)…

[Doug Patterson]

Good News

Took all the stuff ( drills , easy outs , helicoils , bolts etc ) to the boat this weekend .

Long story short , the holes in the intake are all 1.625 deep and threaded to the bottom . I just drilled out the broken off portion ( LH drill / .250 dia ) and it came to the top and was stuck on the bit . The test was easy . Ran a 8mm x 1.25 bottom tap a few times with PBBlaster and air nozzle blow out . Then used a flange head 8mm 1.25 x 40 mm hardened bolt to attach fuel lines stanchion .
I was so happy I forgot to take pics .
Will do next week.

Thanks

[Tony Athens]

Post some good pictures of what you are dealing with..

Tony

[Author]

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