To Hone or Not to Hone

[Paul Ahnell]

Should I ball-hone the cylinders on my '60 Normal engine?

Engine was loosing power and found a seriously leaking #2 intake valve during leak-down test. Heads are in shop to clean up all seats and replace valves as needed. I've pulled cylinders to replace cylinder/block Cu gaskets since everything came loose when I pulled heads. After cleaning up cylinders I see cross-hatch honing is really scarce on the lower part of each barrel. See attached photo of #3. All others are sim. Cross-Hatched at top, shiny smooth below.

Aside from the leaking valve, the car runs well, doesn't burn oil/no smoking out the exhaust. I am not prepared to replace cylinders, pistons, rings at this time so I have not checked dims on cylinders. I understand that honing will not correct any out-of- roundness or taper in the barrels but I think would aid in lubricating what I plan to keep in place now i.e. ring, pistons, cylinders. I'll address the rest when the car is put up for the winter.

What does this wonderful club's Brain Trust recommend re: honing? Any guidance gratefully received by this old rookie. Thanks.

[Martin Benade]

Can you post some more pictures? Usually the bottom part still shows the most cross-hatching, below where the rings travel. The top part looks like it has hardly been run since a rebuild. Is that the case?

[Jacques Lefriant]

i would rigid hone it. but i have access to good equipment. you can correct out of roundness and taper by honing if you are experienced and have the proper tools. the ball hone will improve the surface also.
j

[Paul Ahnell]

Martin: Ansel Adams I ain't, but here are a few more pix. The first pix I sent is #3 Cyl. from above. The break between the hone and smooth is pretty consistent in all cylinders at ~1.75 inch below the top of the cylinder. The PO had the pistons, cylinders, and rings replaced ~ 38K miles ago.

Jacques: I wouldn't think of trying to do a job like that myself with a rigid hone. I know a machinist I'm sure could do it and tweak things as you said, but he's back home in New Zealand for his annual vacation. Always when I need him. Anyway, I thought a ball hone would at least give me the X hatch without causing too much damage.

Martin and Jacques: If this is unusual, what would cause such a condition? Is this dangerous? The X hatch all the way down using the ball hone would still be beneficial now, yes?

Thanks for the education.

[Martin Benade]

I think it is good, just not very much wear since the cylinders were new. I would ball hone to get a surface to aid in reseating the rings. The bottom half does not specifically need honing as there are no rings seating there, but just do the whole thing. It appears to have very light wear for 37 K miles.

[Paul Ahnell]

Martin: Thanks for your insight. It's good to win one every once in a while. I'm thinking a 3.25 inch silicone carbide Flex hone with 320 grit. Sound about right?

[Al Zim]

There are other things you should check and/or replace when you have the engine in this state of disassembly. I am not sure why you would want to destroy the equilibrium of the engine by pulling the cylinders to replace the copper base gaskets. I would be specially concerned if you have the 502 rods in the engine. al zim

[Paul Ahnell]

Al: I would have preferred leaving all as I found them but when I pulled the heads, the jugs loosed from the case so I figured I better re-gasket all. One more SIW; I broke the oil ring on #1 so that cylinder had to come off requiring a new gasket.

Also, as I got into it I decided to re-hone the cylinders. What would you recommend for grit on the 3.25" Flex Hone balls, 240 or 320?

Don't know if I have 502 rods or not. How can I tell? What is your concern?

Thanks for the comments.

[Al Zim]

You probably have the 502 rods. Look on the side of the rod. The first three numbers will tell you what kind of rod you have 502 or 616. The situation with the 502 rods is that the big end of the rod is prone to stretch since it is thin and the shank of the rod does not flair out fr enough to provide strength at higher RPM's The factory changed the construction (read sizing) of the rod bearing and the location of the tab to discourage the use of these rods. This was done in the early 60's. You should have the big end of the rod measured with a dial bore indicator.
I would the finer grit for hoeing. A motorcycle shop may be able to do this for you.
If you have a 4 ring piston with the oil ring below the wrist pin. Zim's may be able to supply you with a replacement oil ring. 800.356.2964 al zim

[Paul Ahnell]

Good info to keep in mind. Thanks for the education, Al.

I contacted your parts Dept. They don't have the cast iron single oil ring, only the newer style double with the spacers/expanders. I'd like to stay with the original: 616.103.314.00.

[Jacques Lefriant]

Hi Paul
Even though my mentor Al is a bit of an alarmist the point he makes is since you are doing the majority of the work and the parts availability situation is probably the best it been since the early 70s it may be best to do the entire engine as if it was going to be the last go round.
j

[Wes Bender]

Paul, this is known as "project creep" and we have all experienced it at one time other in our careers....

[Paul Ahnell]

Yes, I'm familiar with the concept. We used to call it "mission creep"; starts out as a squad patrol and winds up with a Bn. envelopment. The goal is to get my sled back on the road NLT 1 October. It's been off-line for 3 weeks now and I'm starting to have withdrawal symptoms.

[Dick Weiss]

The situation of a ring land about 1/4" below the top of the cylinder will determine the final size/clearances between the piston and cyl.
Piston skirt-to-cyl. max. wear diameter is around 0,02mm (.008") w/cast iron cyl; Less w/chrome cyls.
After honing, the cyls. should be straight as best as possible.

[Jacques Lefriant]

Hi Dick
call me please 619 247 7495