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Triumph TR6 - Aluminum Flywheel Installation...

Ok fellas... Who has had the pleasure of installing a Fidanza flywheel? It goes on about 1/16th of an inch and stops...Do I need to heat it? Or do I need to possibly use the bolts to pull it in the rest of the way? I'm afraid to try anything in fear I may muff things up... My stock flywheel was snug but it went on all the way by hand alone...
DWS Smith

I haven't heard of anyone having problems. Let me check
DON KELLY

Did you mic the 2 openings to compare?
DON KELLY

From a fellow TR owner
"Mine is a very snug fit on the crankshaft, which I understand is the way it is supposed to be. That way it is still tight when the engine warms up. Don't recall what the instructions were, but I installed it by tightening each bolt in a criss-cross pattern, a fraction of a turn at a time. To remove it, I heated it up with a propane torch until it slid off easily."
DON KELLY

Don, I think your right about the snug factor being required for when the engine warms up. The Fidanza seems to be a tiny bit more snug than stock. I may need to call tech support at Fidanza and speak to them. I've read about guys who have used a hot plate to warm the flywheel prior to installation and it goes on easy and cools nice and tight.
DWS Smith

I would ask Fidenza first but both Don's fellow TR6 and the hot plate idea sound feasible although I would probably use an oven versus a hot plate to ensure a more even heating of the flywheel (and avoid possible warping) Maybe even a hot water bath to expand it for a more gentle even heat.
Michael Petryschuk

Actually TR3
DON KELLY

DWS, Steve Pike has extensive Fidenza experience. He'll likely weigh in here before too long.
db
Doug Baker

Doug, that would be fantastic. I would love to get some help from someone that has been down this specific road before...
DWS Smith

I don't know that I would call it extensive...

Some light application of heat is helpful but it needs to be fairly uniform and fairly low. It's a tight fit at room temp as the difference in CTE between aluminum and steel has to be compensated for when everything is at operating temperature.

About 200 to 250°F (~93 to 121°C for you metricated folks) is the hottest I would want it to get and for a shortest time possible. I would avoid a torch unless that is the only thing available to you. It's just too hard to control the temperature with one, it doesn't provide uniform heating and aluminum can have its heat treat screwed up through either too high a temp, too long a time or a combination of the two. If I am recalling correctly, they are using 6061-T651 for their TR-6 flywheels. Here is a link to download the now cancelled MIL-HDBK-5J:

http://docimages.assistdocs.com/watermarker/transient/DFC99E6715CA4B5C8EAED72C043AA872.pdf

Once you've made that ~68Mb download, go to page 3-276, about one third of the way through the document. Figures 3.6.2.2.1(c) and (d) show that the residual properties of the material are relatively unscathed at 250°F and below, so no harm no foul from a long term standpoint. However, if you drop back to 3.6.2.2.1(a) and (b), you will see that the strengths at elevated temperatures take some pretty big hits and it would be easier to damage the part when at temperature. If I'm wrong on the alloy, just go to the appropriate table for the alloy and condition. If the direct download link doesn't work, somebody post back and I'll daisy chain through the steps starting with the Weibull web site.

I also like to use ARP flywheel bolts, I believe they are the ones listed for small block Chevy motors. You can get them already kitted up for the TR-6 motor from Advanced Performance Technologies ( http://aptfast.com/ ).
SteveP1

Steve

The info is appreciated but way over my nut and bolt ability. A simple stick it in the oven at 225 for ten minutes and install was what i was hoping for. I have the ARP bolts and look forward to using them once I figure out how to mount this son of a gun...
DWS Smith

Steve's ears must have been en fuego
DON KELLY

After four days Fidanza finally got back to me with these words of wisdom... Put the flywheel on a hot plate till she is good and hot and get her on the crank before she cools or she will get stuck...

DWS Smith

Oven,
DON KELLY

Don, I mentioned the oven but they in all of their glory said the ring gear may come loose if I heat the entire unit.I'm starting to miss the simplicity of OE parts a bit...
DWS Smith

Good point on their part
You need to ask them where the heck you get a hot plate from
DON KELLY

Had one of them there things way back wheh I was single and livin on my own. Actually it was a dual element.

Rick
Rick Crawford

I got one...use it to heat up the water can that pumps steam for bending wood, but probably a mite steep to ship to AZ. Try the kitchen stove!!
db
Doug Baker

I may very well end up using the stove top. A .65 cent copper washer for the rear seal housing has me on hold anyway...
DWS Smith

Of course. I should have known thg ring gear could become dislodged. ;-)
Michael Petryschuk

When I put a new ring gear on my stock flywheel, I put the ring gear in the oven and the flywheel in the fridge. Dosn't alum. have a higher expansion rate than steel? If so I'm confused as to why the ring gear would come loose. The ring gear would not expand as much as the alum.
rw loftus

RW good point. My head is spinning from all the data... My plan as it stands is this...
As soon as the wife leaves the house, put the unit on the smallest burner of our glasstop stove on medium heat for about ten minutes. Then install the unit before she cools and snug the bolts. After she cools I will remove the bolts, add the included loctite to the threads of the crank with a q-tip, re-install the bolts and torque her down. Sounds easy huh? Well lets see how it all turns out... I was hoping to mate my engine to the transmission over this holiday weekend and shoe horn the assembly back into the car but that darn .65 cent washer that's in the mail for the rear seal housing is killing me...
DWS Smith

The CTE of aluminum is roughly twice that of low alloy steels (4130/4140/4340 and similar) over the temperature range of interest. My basic thought is control of the temperature and that is relatively tough to do on a burner or with a torch.

I would be leery of using a "glass" cooktop. I've never worked directly with the specific material mix used, but my understanding is that it is a partially nucleated ceramic material of vitreous silica and a material from the Lithia-Alumino-Silicate (LAS) family. This allows the material to be rather thermal shock resistant through tailoring of the nucleated material's CTE while impeding devitirification of the silica.

What I don't know is whether or not any tempering is involved in the fabrication of the cooktops. When glass is tempered, it really means that there is accelerated cooling involved to provide a layer of compressive stress around the outer surfaces of the object. The rationale is that glass, and ceramics in general, are very strong in compression. The other side of the coin is that they are very weak in tension due to their very short elongation and the interior of the object is left in tension to balance the compression load induced by the forced cooling process. This technique works reasonably well with glass and may work with cooktops, try looking at the cooktop using polarized glasses/sunglasses. If you see distinct spots in a reasonably uniform pattern, it has been tempered. If it has been tempered, that means that it will be very susceptable to catastrophic failure if you scratch the surface and break through the compressive zone when placing or removing the flywheel and ring gear on the cooktop.

We all have our approach to things. Bottom line is that it is your install and you must do what you are comfortable with.
SteveP1

My head is spinning again... I may just hang the flywheel on the wall(it is pretty) and install my OE unit...
DWS Smith

This is not that complicated.

I support my Triumph habit through understanding materials and structures. I cut my engineering teeth doing materials research, primarily centered around advanced ceramic materials in the early days. That background just happens to have benefits outside of keeping the garage full of Triumphs.

You've been given information on how you might check the "glass" cooktop to see if it's tempered before you commit. Personally, knowing what I know about ceramics from the micro level to the macro level, there is no way in hell that I would use it, but hey, it's your install. As for the hotplate, it's not my favorite, but I'd do that long before I would think of using that "glass" cooktop for the task. Hot plates are readily available from a number of sources and the cost is a lot less than the cost of a replacement cooktop. And that doesn't include the price to be paid explaining to your wife what happened to the cooktop should you kill it.

I did the very barest of searches at the Target website and saw several models listed, I'm sure that other retailers offer similar. Just go buy the hotplate so you can get after it as soon as the washer arrives on the scene.
SteveP1

Steve -

All of the advice is appreciated...
Mostly the one about the cheap hot plate route. I was going to keep the flywheel elevated above the glass stove top with some 1/4" stock but the thought of dropping the flywheel on the surface scares the you know what out of me...

Thanks again I'll be sure to give an update in a week or so once she it mounted...
DWS Smith

The little copper washer arrived and is installed. I decided to roll the dice and use the fancy cooktop to heat the flywheel afterall. After about 12 minutes on high I ran to the garage with the flywheel and she slid right on. After a few moments of joy I realized I forgot to insert the pilot bushing and had to yank the flywheel off and do it again. After the pilot was loaded and 4 minutes on the burner she slid on easy again. I snugged up the bolts and let her cool down for the day. The next dat I removed the bolts one at a time, buttered the female threads on the crank with the included locktite and installed the new ARP bolts.
I must say... This was a tuffy...I hope all the good buzz about the light flywheels proves to be true...
DWS Smith

This thread was discussed between 24/05/2011 and 10/06/2011

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