PDA

View Full Version : '17 J Intake Manifold



jdonaldson
02-09-2015, 07:42 AM
Has anyone ever "resurfaced" the sealing surfaces on an early intake manifold? Due to either corrosion or overly exuberant polishing these have been rounded over to the point that they'll never seal with the brass ferrules. The O.D. measures down to 1.360" at the two ends. Can these two surfaces be turned down and press fitted with an external sleeve?
Thanks For Any Help,
Jim Donaldson

14569 14570

exeric
02-09-2015, 08:25 AM
I had something of an issue like that on my '16J. My intake manifold was not perfectly round so I turned both sides down on the lathe to make them round. I then made my own sealing ferrules out of PEEK. It worked beautifully and seals much better than before. I will only use PEEK for that application.

T. Cotten
02-09-2015, 09:00 AM
Jim!

PEEK is readily available at https://www.mscdirect.com/product/details/63403869

Beware that you will not only want to match your seals quite tightly to the new spigot diameter, but to maximize them to the inside of the gland nuts, reducing the need for re-torques. It is also useful for the seals behind the inlet nipples.

Beware also that the plating must be removed before an ordinary cutting tool can be applied. To the best of my experience from manifolds across my benches, they were never polished before plating, and never so heavily. And unless your lathe is quite large, you will want to counter-balance the eccentric manifold.

....Cotten
PS: Eric!
There are infinite uses for this noble material; Did you really mean: "For that application I will only use PEEK"?

exeric
02-09-2015, 09:18 AM
PEEK is a remarkable material. I used some to repair an ancient Henderson petcock that was leaking. I haven't worked with it as much as you have Tom, so I'm still discovering applications, and ways to machine it.

T. Cotten
02-09-2015, 11:57 AM
Eric and All!

I routinely cut nozzle seals, "repair" bowlnut seals, petcock seal washers, sparkplug indexing washers, and even repair appliances for damaged bowl fuel inlets. It is a useful bearing stock for many applications as well.

With an growing cache of scrap cores, I can offer them by the inch up to 1 1/8" OD at 66% of MSC pricing, plus minimal postage.

My server may eventually curtail my liberty@npoint.net address, so Folks can please email me direct at:
libertynightshift@yahoo.com, or libertynightshift@gmail.com, or libertynightshift@outlook.com

This will help me avoid increasing the cost of my manifold reconditioning services,
Thanks!

....Cotten

jdonaldson
02-10-2015, 01:39 PM
Tom,

Your advice below prompts me to ask another somewhat related question. If I choose to replace the seals behind the inlet nipples, are there any tricks involved in removing them? Any hidden drive pins or such? Is a large wrench and massive torque all that's required?

Thanks Again,
Jim


Jim!

PEEK is readily available at https://www.mscdirect.com/product/details/63403869

Beware that you will not only want to match your seals quite tightly to the new spigot diameter, but to maximize them to the inside of the gland nuts, reducing the need for re-torques. It is also useful for the seals behind the inlet nipples.

Beware also that the plating must be removed before an ordinary cutting tool can be applied. To the best of my experience from manifolds across my benches, they were never polished before plating, and never so heavily. And unless your lathe is quite large, you will want to counter-balance the eccentric manifold.

....Cotten
PS: Eric!
There are infinite uses for this noble material; Did you really mean: "For that application I will only use PEEK"?

T. Cotten
02-10-2015, 03:06 PM
Jim!

Insert nipples that cross my benches are as close as I ever get to one of these machines.
There is no evidence of pinning, which is a good thing when a seal is involved, as re-torques are manditory no matter what material you choose.

Frankly, I would bubble-test them first, and if they don't show a single blister of foam, (and the tapered counterbores are un-blemished or dress-able).... I wouldn't "fix" them!

Anything taken apart becomes by definition: broken.

....Cotten

exeric
02-10-2015, 03:28 PM
Jim, I've done that on all of my Js. The nipple comes out with a good fitting wrench, and lots of muscle. I made a plate so I could bolt the cylinders at their base, and that prevents bad accidents and damage to the cylinder, and it's owner. The plate also makes lapping the valve cages, and exhaust valve much easier, and more accurate.

exeric
02-10-2015, 03:31 PM
I also made that plate to accept Excelsior cylinders for those exact same jobs.

T. Cotten
02-10-2015, 05:10 PM
Jim, I've done that on all of my Js. The nipple comes out with a good fitting wrench, and lots of muscle. I made a plate so I could bolt the cylinders at their base, and that prevents bad accidents and damage to the cylinder, and it's owner. The plate also makes lapping the valve cages, and exhaust valve much easier, and more accurate.Eric!

Just like a "torque plate" for honing, as I pic'd in the current Custom Tools: Cylinder Hone thread?

Its certainly worth the trouble.

....Cotten