Author Topic: Honing tolerance  (Read 5402 times)

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Offline Tom Fox

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Honing tolerance
« on: March 25, 2008, 05:52:00 pm »
A fellow racer in the CTLMRA is redoing his motor and asked this question on another forum:

This is a VANGUARD V-twin engine.


Quote

Does anyone have the tolerances for honing the cylinder I have stock pistons for
a 20hp . This is my first overhaul so any Ideas on not messing this up would be
helpful.

I'm no engine builder (can assemble..just don't know tolerances that well )....If it is just to "FRESHEN UP" and remove the glaze...wouldn't a few passes with one of those dingle-berry hones be suffice?

If there are scratches that can catch your fingernail  and walls need to be cleaned up a few thou...how far can one hone before the piston becomes to small for the bore??

Any help that I can forward to him will be beneficial!

Thanks!



Tom Fox       
Brookfield, CT

Offline Monster

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Re: Honing tolerance
« Reply #1 on: March 25, 2008, 07:01:42 pm »
I 've had some cylinders get pretty scatched up and all I did was run the one of the  Quote (dingle-berry hones) through it a few times looks like brand new . I actully just did my cylinder on my Honda Rancher , I didn't know how this one would turn out , but it to was a success . Still running stock piston and rings , No smoke or hp loss .

Offline mowinmachine

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Re: Honing tolerance
« Reply #2 on: March 25, 2008, 07:18:07 pm »
I just re-honed my rebuild. I've rebuilt tons of engines, and unless the cylinder just happens to have too much wear, I usually just give it a few passes with a hone and cal it a day.Just take it easy with it. The engine I have now used TONS of oil before. But just a simple rebuild with new rings and a hone job did the trick and now it doesn't use hardly any.
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Offline Roger S

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Re: Honing tolerance
« Reply #3 on: March 25, 2008, 07:28:44 pm »
George will recommend just a few passes with a fine ball hone. I used scotchbrite by hand, on bores that still had the factory hatchmarks.

Offline George Herrin

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Re: Honing tolerance
« Reply #4 on: March 25, 2008, 09:35:38 pm »
George will recommend just a few passes with a fine ball hone. I used scotchbrite by hand, on bores that still had the factory hatch marks.

Very good Roger. If you don't have a dingle berry hone and only have a rock type hone and you can see the cross hatch still buy you some medium to fine scotch brite wrap the hone and run the scotch brite thru it. Just a few passes 3 to 6. If you have a dingle berry hone wheather you can see the cross hatch or not quickly moving make 3 to 6 passes. Be sure to keep it very wet wet with some honing oil or wd-40 or something of hat type. You can generally do this twice before you must bore to the next size .020
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Offline Tom Fox

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Re: Honing tolerance
« Reply #5 on: March 25, 2008, 10:06:25 pm »
Thanks everyone!! Will pass along this information!!!
Tom Fox       
Brookfield, CT

Offline markiemark

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Re: Honing tolerance
« Reply #6 on: March 25, 2008, 11:22:10 pm »
Just Wondering Where I Can Get A Hone At? An Is There Different Size For Different Bore
Mark Laird
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I think i can i think i can. Oops I CANT

Offline George Herrin

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Re: Honing tolerance
« Reply #7 on: March 25, 2008, 11:30:43 pm »
Automotive stores  and yup many sizes and grits and types for different size bores.
George Herrin #6
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Offline markiemark

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Re: Honing tolerance
« Reply #8 on: March 25, 2008, 11:34:00 pm »
what would i need to fresh up my 31ci ohv
Mark Laird
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I think i can i think i can. Oops I CANT

Offline George Herrin

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Re: Honing tolerance
« Reply #9 on: March 25, 2008, 11:51:18 pm »
Thats hard to say with out seeing the condition of it. Gasket set rings rod at the very minimum.
George Herrin #6
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Offline bountyhunter

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Re: Honing tolerance
« Reply #10 on: March 28, 2008, 04:24:35 pm »
 What grit do you use George on your hone??