Another Mannifold Leak -- 55 Front 48 Rear

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jank1331
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Another Mannifold Leak -- 55 Front 48 Rear

#1

Post by jank1331 » Mon Nov 29, 2010 7:18 pm

I found a leak in my rear head from the rivet hole and the intake nipple. After investigating a bit I found that the nipple was loose ( could turn 1/4 rotation by hand ) and the rivet hole that was filled with JB weld because it was a bit munched up, probably from the removal. The rear head is a 48 and the front is a 55 so I have the two different styles of nipples, obviously the rear was retrofitted for the O-ring style front. I know some of you will whince about this but I couldnt think of another way to reapair the rivet hole. I tapped it to fit a stainless set screw to hopefully seal it with seal lock fluid weld. I think also that the nipple needs to be torqued down a bit
My questions:
1 Where can I get a spanner wrench tool to install these types of nipples?
2 How does the seal lock fluid weld recommended by Cotten cure? (have not heard back from the company yet) I have tried a few nut/bolt tests over night and it doesnt take much to brake them apart. Is the application wrong?
3 Planning on using the seal lock for the nipple and the set screw, opinions on if it will work or not.

Thanks for the input

Steve
48 Rear 10.JPG
48 Rear 7.JPG
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steinauge
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Re: Another Mannifold Leak -- 55 Front 48 Rear

#2

Post by steinauge » Mon Nov 29, 2010 8:55 pm

I believe the setscrew is a good repair.If I have a loose ,leaky adaptor of that type I use JB weld on the threads.Never had any trouble with it yet and it doesnt seem affected by the alky in the fuel.The spanner I have that fits those came out of a bicycle tool kit!! If you dont have that it would be easy enough to make one up from several types of shock spanners I have seen.For that matter you could cut one out of a scrap of 3\8 plate and use an old roller bearing for a pin.

Panacea
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Re: Another Mannifold Leak -- 55 Front 48 Rear

#3

Post by Panacea » Mon Nov 29, 2010 9:03 pm

I made a spanner to fit mine when I had the intakes re-threaded, problem was in order to fit into the holes in the nipple, I had to bend the handle on the wrench to clear the head. Then bend it the other way for the other head. I'd like to see the real tool, it must have a lower profile...Mike

Cotten
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Re: Another Mannifold Leak -- 55 Front 48 Rear

#4

Post by Cotten » Mon Nov 29, 2010 10:17 pm

Steve!

Seal-Lock "Fluid-Weld" is marvelous stuff, and still has its merits for other applications, but in the decade since the VI discussion, it has fallen out of favor. Probably because it is not a structural adhesive and not meant to fill macro voids.

JBWeld (original formula) is as good as anything considering today's digestive fuels.

I am against setscrews for two reasons: Straight threads do not seal themselves, and they look like a herpes sore.

The original design expected the threads to be sealed by the shoulder of the nipple butting against the counterbore of the head. (Knucks sensibly had a thin lip off of the head casting that would bite into the nipple.) The rivet sealed itself entirely by interference fit and expansion from peening.

But it works great.

If you tap the head for a setscrew you are making a huge hole, and increasing the chances of the casting cracking.
(Been there done that.)

Without having your head in my hands, I would say careful cleaning and re-installation of the nipple with JBWeld (Devcon, etc...) is the only alternative in this instance. And I would just fill the rivet hole while you are at it. (The rivet was to prevent plumber's nuts from backing the nipple out; clamps should be no problem.)

As far as a tightening tool, mine won't work, as your photos show the spanner hole to be quite deep within the head.

How much gap does your manifold have on each side?

....Cotten
PS: No matter what you do, bubbletest.

jank1331
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Re: Another Mannifold Leak -- 55 Front 48 Rear

#5

Post by jank1331 » Tue Nov 30, 2010 12:12 am

Cotten,
That Herpes is a bitch! I know its not perfect but there was JB weld in the original rivet hole which was leaking, Im thinking the set screw with JB will make it stronger; we shall see. As far as the gap is concerned, about .020 on either side between mannifold.

Thanks

Steve

Cotten
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Location: Central Illinois

Re: Another Mannifold Leak -- 55 Front 48 Rear

#6

Post by Cotten » Tue Nov 30, 2010 12:57 am

Steve!

Yes, Herpes is a bitch.

.020" on each side sounds fantastic!

Let the goober set up good,

....Cotten

jarhead
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Re: Another Mannifold Leak -- 55 Front 48 Rear

#7

Post by jarhead » Thu Dec 02, 2010 12:34 am

My Spanner wrench. Maybe this will work for you in the future...
http://www.jockeyjournal.com/forum/show ... ert+repair" onclick="window.open(this.href);return false;

jank1331
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Re: Another Mannifold Leak -- 55 Front 48 Rear

#8

Post by jank1331 » Fri Dec 03, 2010 6:42 pm

Jarhead,
Thanks for the input, wasnt thinking of a socket type tool, so a great idea. Ill have to try one out.

Steve

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