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Tinster
12-25-2008, 01:07 PM
I'm having a blast reading the shop books and technical books
Frank gave to me for Christmas. So many, many things I never
knew existed in a car engine.

Of course I went directly to the "thrust washer" part.

But then I was reading about "cam shaft end float"
I know a whole bunch of guys (TRBill for one) are having
a miserable and costly go with their cam shafts.

Q: Do I need to start to worry about cam shaft end float
as well as thrust washers falling out into the oil pan?

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< <<<<<
The book showed installing the new thrust washers with
the engine upside down, out of the car. (BLARGH!! -
that's months and months on jackstands)-I've never removed an engine.

The thrust washers look like metal arches to me. Are they
simply pounded in tight with a hammer? The book didn't say.
Darned things worry me to death whenever I drive the car.

I've seen a few engines like totally blow up on the expressway.
The entire car enveloped in smoke and then coast to the side of
the road, dead. It that what happens when TR6 thrust washers fall
out? KaBOOM- engine blows up in a huge cloud of smoke?

thanks,

dale

martx-5
12-25-2008, 01:43 PM
Instead of worrying about the end float on your crank, just go and get a dial indicator and measure it. This way you will know where you stand. Then maybe you'll be able to lay this issue to rest or send the car to the crusher. And no, they are not hammered in.

Tinster
12-25-2008, 01:55 PM
Art- WHERE is the cam shaft end located? Is it
behind the timing chain front cover plate?

What is a dial indicator and where do I purchase one?

thanks

d

TR3driver
12-25-2008, 02:04 PM
Camshaft end float is almost never a concern, except when assembling a motor. So no sense checking it, IMO. The process of checking it is more likely to cause problems than leaving it unchecked.

The crankshaft thrust washers fit loosely into a cavity that is just the right shape and size. Two sides of the cavity are formed by the engine block (on a TR6), while a third side is formed by the thrust surface on the crankshaft. So they can only fall out when extremely worn, so thin that they will fit through the small gap between the cap and the crankshaft.

And no, even when they fall out, the engine doesn't "blow up in a huge cloud of smoke". Generally it will even keep running, but make horrible grinding noises if you try to use the clutch. Usually you can still limp home, by not using the clutch (same techniques as when the clutch hydraulics fail).

But you can easily avoid that by making an annual check (or every 15,000 miles whichever comes first) for gross endplay. No need to measure precisely, as the washers have to be worn way, way outside the given tolerances in order to fall out.

But with a workable dial indicator with magnetic base usually under $25 at ENCO (https://www.use-enco.com/CGI/INPDFF?PMPAGE=336&PMCTLG=00) ; might as well get one and use it.

davidk
12-25-2008, 02:22 PM
Merry Christmas Dale. Here's a good website that shows using the dial indicator Randall mentioned. This is also a good site to buy replacements if you ever need them: https://www.customthrustwashers.com/triumphendfloat.html

Scott_Hower
12-25-2008, 06:51 PM
Dale-

For starters, have Wendy depress the clutch and watch the nose of the crank/damper with the car running. If it moves a perceptible amount, you've got some end-play in the thrust washers.

You worry too much. Just drive it for crying out loud.

Scott_Hower
12-25-2008, 06:55 PM
Art- WHERE is the cam shaft end located? Is it
behind the timing chain front cover plate?

What is a dial indicator and where do I purchase one?

thanks

d

Forgive me, but you are some sort of structural engineer and don't know what a dial indicator is? It's a measuring tool where precision is required.

You can get one just about anywhere. Sears for example.

Brosky
12-25-2008, 06:58 PM
Dale,

I say this with all due respect.

This is absolute proof that a little knowledge can be dangerous. Just because you now know about some particular engine tolerance or setting does not mean that it will become a problem for you in the near or far off future.

I think that the general consensus of this forum is that you should drive your car and stop worrying about what could fail next. That's like trying to pick lottery winners. Not one person has offered a solid suggestion as an answer for any parts to be replaced on countless threads where you've asked about these subjects, so go forth and be happy like the rest of us. And your car has more new parts on than most cars here. We just drive our cars daily or whenever possible and deal with any issues as they come up.

Or.............you could simply tear the car completely apart from the front end to the rear and spend the next two years rebuilding what you've already rebuilt once and then some new stuff never touched yet. And once that is done, start from the rear and do the same exact thing, but in reverse order. That way you can always be working on the car, but it will never have a chance to break down because it will never, ever be driven.

KVH
12-26-2008, 02:59 AM
Yeah, but some of us were born to worry.

So, when I replaced my cylinder head gasket, I replaced the timing chain, tensioner, front cover oil seal, lifters, and pushrods; and checked my end float on the cam.

Tinster, if you do it (and I agree with the comments, including from TR3Driver), remember to first put the bearing back on and tighten it down, then slide the cam forward after fixing a dial gauge to the face. I think I had .003 float, whatever the spec was, I was right on it.

I bought my dial gauge at Harbour Freight for $18.

Then, due to some limited pitting, and a continuing penchant for worrying, I replaced my cam, too.

I'll probably never my dial gauge again, though I'll tell my wife that I use it regularly when I check the TR Front and Lower By-way Gears, or something).

Good luck.


Important PS:

I would have lacked the confidence to do any of what I did without this Forum. TR3Driver, George Hahn, Tdskip, Brosky, all you guys. Like others said, it's probably best to control the impulse to fix what isn't broken. In my case, I had to pull the head, then when I saw pitting on the lifters, that led to a new cam. The story goes on, but I then replaced the pistons, rings and liners, too, and the rod bearings, and the oil pump rotor. I'm not ashamed, but I know I went overboard. I felt the need to gain confidence on the inner engine, the use of plasti-gauge, etc. I didn't pull the crank, but that's about all I didn't do. I even replaced the motor mounts and readjusted the distributor gear end float. When I'm in my '80s in the year 2040 and on a fixed income I want to know I can rebuild that TR of mine all by my myself.

70herald
12-26-2008, 04:13 AM
Dale
When I pulled apart my engine to rebuild it, the ONLY things in spec were the cam shaft end float and thrust washers. Every thing else was warn out. Just go for a nice long drive.

vagt6
12-26-2008, 09:28 AM
<span style="font-weight: bold">LBC care and feeding</span>:

Get a factory manual and perform ALL required/scheduled maintenance. You can learn most of it, let pros (or maybe semi-pros) do the rest;

Trust, and heed, your gauges;

Don't thrash your LBC unless you have a big budget;

Then, <span style="font-style: italic">just drive</span>! :thumbsup:

Brosky
12-26-2008, 10:18 AM
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Yeah, but some of us were born to worry.[/QUOTE]

Kent,

That is completely understandable, especially in Dale's case where he had a series of issues befall him in a short period of time.

BUT, he also has driven the car for nearly 2,000 miles, trouble free. I don't count the recent idle problem, that is an issue thrashed to death here and the couplers will fix it.

So my advice was neither condescending or glib. I just wanted to show that at some point in time, if you want to actually use the car for the purpose that you bought it, which I presume, is to drive around the island, that time is now. Or it will be come a never ending cycle of "what about this?" or "while I'm in this far, I might as well" and the goal has been lost.

Or, maybe Dale just prefers to work on it 99% of the time, which is fine, if that's his choice.

Tinster
12-26-2008, 10:33 AM
[quote=Tinster]Art-
Forgive me, but you are some sort of structural engineer and don't know what a dial indicator is? It's a measuring tool where precision is required.

You can get one just about anywhere. Sears for example.

<span style="color: #660000">Forgive me Scott, lauguage problem. I have several "dial indicators"-
some I had custom designed and constructed for my hurricane simulation
testing. We refer to them as pressure gauges because we convert the
needle readings of movement into hurricane wind pressure. And yes, mine
are all calibrated and certified by The National
Institute of Standards and Technology.

thanks for the heads up.

dale</span>

TRDejaVu
12-26-2008, 11:02 AM
Frank, now look what you've done :crazyeyes: :wall:

Tinster
12-26-2008, 11:16 AM
Paul- at this stage, my concern is purely financial.
I cannot afford to replace/repair a blown up engine.

You know how badly this poor car was driven into the
ground by the P.O. I have more NEW parts on the car
than I have original parts. I have no reason to believe
he took excellent care of the engine; given 3 years without
an oil change.

If I can repair some small engine part that is failed,
I need to do it before the engine blows up.

My TR6 restoration funding is all used up and no more
will be arriving.

best regards,

dale

Brosky
12-26-2008, 11:41 AM
Dale, I understand, but you do know that once you open up something, it truly becomes Pandora's Box.

I don't think that I can help anymore other than suggesting for the last that you just drive the car. This is far beyond the way that I would approach it, but that's me and you are you.

DrEntropy
12-26-2008, 04:34 PM
I just *knew* I need not have read this thread. But as the ever curious cat...

Dale, this thrust washer issue is a well-and-truly bludgeoned equine. Dead. You've had the same opinion from about anyone here who offered one. DRIVE it.

To now READ the manuals and begin to stress over cam end float is NOT what you need to be doing.

Driving the car is what you should be doing. Said yourself there's no more funding for repair of the thing, trying to GUESS what will cause its demise is an exercise in crystal ball gazing. Crankshaft thrust washers are indeed "half moon" looking. They wear over time. A ~long~ time if the clutch isn't ridden unnecessarily. The engine will not come apart in a cloud of smoke if they DO wear. As for cam float, how would you address it if it WERE a bit out of tolerance range?!!?

Fergetaboudit!! DRIVE!!! YOU'VE told us it's impossible for the car to be rehab'd if it breaks in a big way. There's NO way short of a complete tear-down and refurb to know what's in or out of tolerance. Be fatalistic about it. Drive it and tend to the regular maintenances. When it finally does succumb to entropy, it's headed for the crusher (in your own words) anyway. Why amp over it. It either will or will not continue to run. A preemptive thrust washer replacement won't do anything for crankpin wear, or a dozen OTHER things happening in there with time and prior sin.

And do NOT misinterpret what I'm saying: this is not belittlement. Rather a friend trying to get you to adjust your outlook on what may or may not be "the last test drive". Just drive it. If it quits for some "little" reason, we'll help. If it grenades, we'll hold a virtual memorial service for it.

GeeBee1
12-26-2008, 05:17 PM
And do NOT misinterpret what I'm saying: this is not belittlement. Rather a friend trying to get you to adjust your outlook on what may or may not be "the last test drive". Just drive it. If it quits for some "little" reason, we'll help. If it grenades, we'll hold a virtual memorial service for it.


:iagree: 100% and couldn't have said it more elegantly

Pat

Scott_Hower
12-27-2008, 08:15 AM
Forgive me Scott, lauguage problem. I have several "dial indicators"-
some I had custom designed and constructed for my hurricane simulation
testing. We refer to them as pressure gauges because we convert the
needle readings of movement into hurricane wind pressure. And yes, mine
are all calibrated and certified by The National
Institute of Standards and Technology.

thanks for the heads up.

dale

No problem Dale.

As a professional who has "custom designed and constructed tools" and knows/interacts with the NIST, I guess I mistakenly assumed you would know what a common dial indicator is. Next to a sliderule, it's about the most basic of engineering measurement tools.

Me thinks you need to seek attention less and drive your car some more.