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Loctite Solution

Thanks to Buford T. Justice.  updated 11/09/02


Doug Lewis is welding camshafts for $400 labor, Vadim will be offering replacement camshafts for $800-$1300 (parts only). Welding requires both a talented mechanic and welder. Vadim’s delivery date is yet to be announced.

As much as I respect both Doug and Vadim, I was looking for a third alternative. Loctite makes makes an industrial line of adhesives and bonding agents that can glue one end of the rainbow to a pot of gold. (Customer must supply both rainbow and pot of gold) The trick is using the correct product, Loctite must have a thousand products in their industrial catalogue.

Loctite Threadlocker 294 is High Temp (-65° F – 400°F), wicking grade (very low viscosity), and oil tolerant adhesive that can work it’s way in to already assembled metal threads and will make a press fit about three times stronger. Is 400°F enough? It should be but honestly I don’t know.

I would not trust this to fix a failed sprocket but hope it may be enough to prevent failure of a "good camshaft". The good news is this is not expensive, parts cost about $20. It wicks so you don’t have to disassemble, (you can’t anyway). Minimal preparation is required. If you later choose to weld that is OK. This Loctite cures to work in 10 min. and develops max strength in 24 hours.

I hope to work up a full photo "how-to" procedure for undressing a V8SHO as far as the cams, but here is the specific details of the Loctite part of the procedure.

Get some non-linting shop towels and cover the top of the engine (cams) except the 4 sprockets. It is imperative you don’t get any stray loctite some place it does not belong. It could ruin a bearing, lobe, or shim surface.

You MUST  use some "Non-Flammable Electrical Contact Cleaner" available from any electrical supply shop or Loctite which is volatile and leaves no residue to clean oil from the splines with in the hub. This stuff is a mild solvent so if you use it you should change the oil and filter after the procedure. Is it worth using a cleaner if we are using an oil tolerant version of Loctite? I don’t know, is it worth spending 8 hours labor and then scrimping on preparation?

Somehow you have to bump the engine two or three times to apply the loctite 294 every 180°-120°. I don’t think you can apply from both sides, hence the importance of getting a loctite that wicks very well. I think you can put a big nut on the crank pulley and turn the engine over just a little at a time. You would have to be able to get under the car, so you need the car on ramps or a lift.

This Loctite method may work, may not be as strong as welding; each method has it’s own strengths and weaknesses. You have to make your own choices and live with them. Welding may void warranty claims, I don’t see how Ford could get ugly about a well hidden loctite job. If a cam was making noise I would recommend either welding or camshaft replacement before failure. I would not expect Loctite to hold once a sprocket has started to slip.

Last issue, IF Ford did extend the warranty, they could get ugly about welds, I don't think they would notice loctite or be unhappy if they did.

Product_294.pdf    Threadlock 294 Tech Data Sheet (right click, save as) 

threadlock.pdf  Loctite Threadlock products  (right click, save as) 

see also www.loctite.com for a distributor near you. 


If you are looking for a procedure to remove the valve covers in order to access the cams for the "loctite" fix, I wrote one a while ago:
http://www.v8sho.com/SHO/valvecovers.html

Mike

Our collective thanks to Mike Holhut for saving out buttocks with his foresight and hard work.


Hello Chris

I can not really endorse this as a solution only a band-aid. Both cars that I did this too have since had the cams welded at FPS. A weld job is the only thing I would consider permanent.

Paul


----- Original Message -----

From: Chris Kepus
To:
'Paul Nimz'
Sent: Wednesday, October 09, 2002 2:07 PM
Subject: Loctited Cam Sprockets

Hi Paul,

My welder may have flaked out on me. Won’t return calls....maybe that’s a clue. L

I was studying your comments on V8SHO.com on the loctiting you did on your cams. It has been almost a year since you posted the information and it seems it worked for you just fine. I would like to talk with you about the process. If you will pass along your phone number, it would save us both from typing. J

Thanks,
Chris


11/09/02

Hi Tim,

My name is Phil Silano and I have a 98 SHO, Black with just under 65K miles. I bought the car two years ago with 32K miles from our local Ford dealer. It belonged to the owners nephew.

I came across your website about two weeks ago when I was looking for info on service requirements for the timing belts. The manual didn't list any but I wanted to be 100% sure, your site answered that question, no service needed.

Unfortunately reading about all the cam failures made me absolutely paranoid. I wouldn't even turn on the radio so I could hear every noise from under the hood. My wife and I love this car, so getting rid of it was not an option. I'm a pretty good backyard mechanic so today I dove in to repair the cams using the Loctite option. Both the pinning and welding options made me very uncomfortable. I work in aerospace and know a bit about the properties of various metals and the problems that can be caused by doing something without a full knowledge of the stresses that are being induced into the parts. After reading through the data sheet on the Loctite it seemed like a safe approach. I'm still concerned about thermal expansion of the metal parts and the Loctite but everything has some risk involved.

Whoever posted the valve cover removal procedure, thank you, thank you, thank you. You saved me a lot of time and effort.

Anyway, I started at 10:15 this morning and had the valve covers off by 12:30. I didn't remove the rear surge tank supports from the head, instead I took the intake runners off the top of the surge tank. More bolts but much easier to reach. Putting the surge tank back in was a little hard to position but not too bad, about ten minutes.

A word to the wise, DO NOT clip the end of the Loctite bottle applicator. Use a pin hole. I forgot the description of the Loctite procedure someone else posted on your site. I clipped the applicator and had one hell of a time controlling the flow from the bottle. BTW, Loctite 294 doesn't seem to be available any more, the new number is 290. Also used Loctite cleaner/primer 7679. Just for the hell of it I tried the Loctite on two pieces of steel left over from another project. This stuff cures hard and holds like ..., well like Loctite.

Put it all back together and finished about 5:30. It may be my imagination but the car seems to run better. A few of the clamps on the intake runners seemed loose so some small leaks may have been fixed in the process.

One other suggestion, wash the engine before starting, remove the pretty cover and wash it again. Let it dry completely then go to work.

Feel free to post this if you think others can benefit from my experience.

Two other subjects;

Tires, Pirelli P7000 Super Sport, much better than the originals in every respect except life. Maybe 30K of spirited, not breakneck, driving.

Also, this motor has always been noisy for about two seconds after starting, then it's smooth and quiet. Seems like it's waiting for the oil pressure to come up. Is this normal?

Phil Silano
Ballwin, MO


11/18/02

I am the one who first thought of this, and Paul Nimz and I were the first two to try it.  Together we agree, while Loctite may be better than nothing it is not as robust a preventative procedure as welding. Since then we each  independently went down to FPS and got our cams welded. We just don't have the level of confidence in Loctite that we should for this application given the cost of failure.

I don't regret using Loctite, it is much better than nothing. The cost was small and we did the labor ourselves. It just does not seem as robust a solution or as trustworthy as welding. On the plus side it should not void a warranty and a Ford dealership might try it for you, when they certainly would be reluctant to weld them for you.

Buford


The destructive force is the jerking about (uneven turning force) which breaks apart the joint.

30% is OK but welding has to be 300% stronger

I will be most happy with 0% cam failures, I don't know that Loctite will accomplish that..

Tim


----- Original Message -----
From: <Ge42ma@cs.com>
To: <twright@one-eleven.net>
Sent: Wednesday, December 25, 2002 9:56 PM
Subject: V8SHO.com%20Website

I spoke with a locktite technical rep.  He said that the loctite would add about 30% strength to the cam/sprocket contact…if you could remove the sprocket and press it back on over a loctite painted surface.

 


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