Valve Guide Reamer Recommendation

[YL82]

I need to buy an 8mm Valve Guide Reamer. Also, will need reaming oil of some sort.

Plan to use one in my 3/8" variable speed drill. I have 4 new Valve Guides from Mikesxs.

Lots of choices out there...

What are Mikesxs Valve Guides made of? Bronze, Cast Iron, Plain carbon Steel?

Do I need a high speed steel reamer or a carbide reamer?

Other choices include straight flute, spiral flute, etc.

Is the drill supposed to be run in reverse (counterclockwise) during reaming?

On another thread, I asked about whether a 8mm Flex Hone would eliminate the need for reaming, but I have doubts that enough metal will be removed.

Any recommendations on what 8mm reamer to buy would be appreciated!!

 

[plane_ben]

I just put four Mikesxs valve guides in my head. They looked like plain carbon steel. Mine didn't require any reaming, just a little emery cloth wad cutter at the very top where the installer punch rolled the edge slightly.
If I were buying a reamer, I would go with an adjustable one.

 

[jd750ace]

Straight flute HSS, and DON'T turn it backward. It may even be advisable to use a tap handle and run it by hand. One good tilt can trash your guides. You can use motor oil to lube it. If you do use a power tool, keep the torque high, the speed low, and the feed rate moderate. The drill should not bog down and the reamer should not chatter or squeak.
Spiral flutes work much better in fixed machines and are typically used in situations where a fair amount of material is coming off in each pass. McMaster Carr is a good place for standard size reamers.

 

[YL82]

I haven't installed my new guides, so I'll take a wait and see approach on whether they will require reaming. Sure hope not....

My head holes were pretty pristine after I pulled old guides out and my measurements showed that I can go back with standard valve guides, so I'm hoping for the same outcome as you, plane_ben.

I had seen a dude on youtube reaming valve guides (with drill in reverse) on some automotive cylinder head.

I wil heed your advice, jd50ace. Thanks.

 

[Speedthriller]

After installing your new guides, I am pretty sure they require reaming. Like jd750ace already mentioned, do it by hand with a tap handle. You have more feel that way. It's pretty easy. And indeed, dont turn your reamer backwards!

 

[jd750ace]

I've only done them on aircraft engines, and we always done them by hand. Old Continental engines were bad for sticky valves. Marvel Mystery oil would free them (and keep them that way if you used it regularly in the fuel as a top end lube) but we changed a few sets along the way when they had abnormal oil consumption and coked up valves. Always done them by hand.

 

[plane_ben]

After installing your new guides, I am pretty sure they require reaming. Like jd750ace already mentioned, do it by hand with a tap handle. You have more feel that way. It's pretty easy. And indeed, dont turn your reamer backwards!

I agree this is usually the case. I was expecting to do that very step. But my valves slipped right in until the stem got tight right at the top of the guide. They just needed a little buff to clean up the inside edge and they (the valves) fit perfect.

 

[YL82]

I'm thoroughly convinced that I should ream by hand. I will have much less anxiety (and risk of !%#€#!! - ing up) doing it by hand than by using a drill.

After watching that YouTube video, I definitely had some ...different... ideas of how valve guide reaming should be done, so I'm damn glad that I started this thread. The knowledge base and experience on this Forum is awesome.

Thanks for all of the feedback!

BTW: Below is YouTube video that I have mentioned a time or two....

 

[rebel542]

You're going all out. Are your electrics still up and running?

 

[YL82]

Yep, I sure am. Wiring harness all done.

 

[YL82]

As far as the Tap Wrench to use with 8mm Reamer, will a shorter T-Handle Tap Wrench suffice or will I need a longer Straight Handle Tap Wrench? I have a standard T-handle one, don't have a straight handle.

Looks like the difference lies in the leverage provided and the Straight handle ones are made to accomodate a square shape on the tool shank.

 

[jd750ace]

As long as you are careful with your initial alignment and take your time (thank you captain obvious!) your handle should work fine. You are making a clearing pass, not plowing, so it shouldn't require much leverage.

 

[YL82]

OK. Thanks.

Perhaps a stupid question, but I'd rather not make any incorrect assumptions (you know, like reversing drill direction):

Which direction do I need to ream, toward combustion chamber or toward valve spring end?

 

[jd750ace]

I've always done them outside in, but I'm not sure it makes any real difference.

 

[YL82]

Do I need to use a special Reaming Oil or will any garden-variety lubricant/oil do the job?

I've been on McMasterCarr.com. In the metric hand reamers, they only offer the Spriral Flutes whereas the fractional reamers come in both Straight & Spiral Flutes.

OK to go with 8mm Spiral?

Or perhaps go with 5/16" (.3125") in a Straight Flute which is closest to 8mm (0.315") ?

I appreciate your help, jd750ace.

 

[jd750ace]

Any lube will work. It's mostly flowing cuttings, and not really cooling with hand reaming. McMaster Carr will grind a straight flute reamer for you. You can probably specify a pilot section diameter and length as well, to keep you nice and straight.
http://www.mcmaster.com/#chucking-reamers/=n5a2bq

 

[YL82]

I called McMaster-Carr and at their suggestion ordered a Straight Flute, Round Flank, HSS Chucking Reamer in 0.3145". Pretty close to 8 mm or 0.31496".

I'm assuming that I can hand ream ok, but I guess in a standard Tap wrench and not a straight handle tap wrench that takes square flank.

 

[Olie]

Are you still using your stock valves?

 

[YL82]

Olie,

I've got new OEM Intake Valves to install, but will be sticking with the stock Exhaust Valves, which I've cleaned up.

 

[YL82]

Deleted.