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rlandrum
12-15-2008, 10:34 AM
We recently installed the dash in our TR3A project and wanted to test the electric connections. When we attempted to test the starter, we found that the engine wouldn't turn.

This engine turned fine while it was being rebuilt. It has not been turned since being installed in the car. I cannot seem to recall exactly when I last turned the engine, but it was definitely prior to the installation of the valve cover, and may have been prior to installation of the fuel pump and distributor assembly. It was not turned after installation of the flywheel or clutch.

We have ruled out the starter (we removed it). We have ruled out the distributor being the issue (we removed it, too). We find it unlikely that a foreign object has made it's way into the engine as I'm generally very careful and rotated the engine several times prior to installation in the car. We ruled out overcompression (by removing the spark plugs).

We've tried several ways to turn the engine. We attempted to turn the dog bolt with the car in neutral. We put the car in first gear and attempted to push the car.

Our best guess is that the clutch bolts or flywheel are hitting the block, preventing the crank from turning. But before tearing into it, I wanted to see if the board had any similar experiences and if so, what was the culprit.

emmett1010
12-15-2008, 10:37 AM
The flywheel to crankshaft bolts are too long.
Don't ask me how I know.
Emmett

Mickey Richaud
12-15-2008, 10:39 AM
Does sound like a flywheel/clutch issue, particularly since you didn't turn the crank after installing them. I believe there was a similar thread here recently; if you do a search it may turn up, and it may relate...

Looks like it's time to pull it back out. :frown:

rlandrum
12-15-2008, 11:49 AM
Ok... a little bit more information... While I was first attempting to install the clutch, I found I was unable to tighten the bolts all the way down because they were bottoming out in the flywheel holes. (The holes don't go all the way through.)

So I ordered new ones from Moss and used them to attach the clutch.

I seem to recall that there are 4 bolts holding the flywheel to the crank (and a alignment pin), and 8 bolts holding the clutch to the flywheel. I don't believe there were any other bolts in the flywheel. The crank bolts are almost certainly not the issue, and I just can't see how the clutch bolts are interfering with the block.

Maybe the oil seal bolts are hitting the flywheel?

Are there any block holes that, if a bolt were too long (by 1/4-1/2 inch), would cause the crank or cam to hit?

TR4nut
12-15-2008, 11:58 AM
Yeah, this sounds a lot like Frank's problem discussed about a month ago:

Stuck tractor engine (https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/507860/8)

alfa33047
12-15-2008, 12:25 PM
Hi Landrum, Did you put the clutch disc in backwards? Check your clutch arm to make sure you have some free travel in your throw out bearing. Did you put too many washers on your rear seal covers so that it is hitting the flywheel? You will more than likely have to remove your transmission. Good Luck, Bill C. Mesa, Az

rlandrum
12-15-2008, 12:42 PM
Brilliant... The flywheel to crank bolts. I guess the tranny is coming out tonight.

Thanks for the help!

Mickey Richaud
12-15-2008, 01:29 PM
Yeah, this sounds a lot like Frank's problem discussed about a month ago:

Stuck tractor engine (https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/507860/8)


Whew! Thanks - I thought I'd read that here!

alfa33047
12-15-2008, 05:25 PM
Hi Landrum, I meant to say the bolts that hold the 2 piece rear seal cover. I have seen mechanics (me) place a flat washer and lock washer on the bolt that holds the cover plates on and then when the flywheel is bolted and torqued down, it will rest on those bolts and keep the motor from turning. Good luck, Bill C.

Tinster
12-15-2008, 05:36 PM
WE had a devil of a time getting the engine in my car operational.

I certainly feel for ya!!

dale

https://i134.photobucket.com/albums/q101/TinsterTR6/NewEngine.jpg

rlandrum
12-15-2008, 06:27 PM
WE had a devil of a time getting the engine in my car operational.

I certainly feel for ya!!

dale

https://i134.photobucket.com/albums/q101/TinsterTR6/NewEngine.jpg

Nice small block Chevy there, Dale...

You know how they sometimes call old heavy parts "boat anchors"... Well, it looks like whoever last owned that SBC above took it a little too literally.

CraigLandrum
12-15-2008, 11:27 PM
Just read the link to the thread discussing Franks stuck engine and it sounds similar to me. Hopefully it will be the flywheel to crank bolts being a tad too long. Man, we really, really don't want to yank that engine back out. I recall it turned like butter before the flywheel went on, but with both the distributor and fuel pump installed. Neither of us could recall turning it afterwards so I'm betting that's the problem.

Unlike Frank, when we tried to turn the engine it never moved even a little bit and we were concerned about putting a lot of torque on it in case something snapped. My son indicated he would pull the tranny tonite and check those flywheel bolts. I've got my fingers crossed. I mean hey, we had just finished installing the dash and had finished all the dash wiring, heater hoses, cables, everything - even the windshield washer pump and tubing. We were right at the point where we sorta thought perhaps, maybe, we could almost begin to see a glimmer of light at the end of this tunnel :-)

Mickey Richaud
12-16-2008, 08:51 AM
Never fear, Craig - just part of the game. We've all had similar "challenges" to our restorations. Makes the end result of firing it up and driving off for the first time all the more satisfying!

Mickey

rlandrum
12-16-2008, 10:48 AM
I did manage to get the transmission out last night and I was able to see that the flywheel bolts are resting on the aluminum oil seal. I'm going to assume that the oil seal is not damaged. (I never tried to force the engine to turn, so hopefully it didn't break anything.)

To correct my father slightly, when I turned the dog bolt, I got perhaps 5 degrees of movement from the crank. Not very much at all.

I find it curious that the bolts I used were too long. I reused the original bolts. The originals did not have lock washers, so when I reinstalled, I did so without them. I don't recall seeing any damage to the original oil seal, which suggests that it may have been thinner than the new oil seal flange. I suspect that lock washers will make up the difference.

TR3driver
12-16-2008, 11:05 AM
Original usage was lock tabs, not washers. As I recall the discussion, using lock washers is a bad idea (although I don't recall just why offhand, something about flexing during normal operation). The recommendation was to shorten the bolts instead, and use Loctite.

Or if you want to stick with the tabs, TRF has them under P/N 56524. $1.50 each.

Tinster
12-16-2008, 12:14 PM
Randy- you are aware I know nothing of Triumph
Auto mechanics so take this with a grain of salt.

If Dim Dale removed an original fastener (or a Pedro-ized
metric fastener) I installed brand new fasteners of high quality.

I know first hand what a b-itch it is to pull a tranny.
Every fastener I installed was brand new, Roadster Factory
or American made grade #8 steel.

I have never reused a fastener in my bucket of bolts car restoration.

d

prb51
12-16-2008, 12:57 PM
Guys,
I reused the stock flywheel bolts without the tab washers (didn't have any) and used locktite instead.
No interference issues.
Looking at a friends rebuilt TR3 motor sans tranny the flywheel bolts would have to be 3/16ths to 1/4 in. longer than stock to hit anything.
Maybe if your thrust washers were totally shot and allowed huge crank movement fwd/bkwd there could be an issue but that wouldn't be the case on a rebuilt motor.
Am I missing something?

rlandrum
12-16-2008, 01:34 PM
I cannot say with absolute certainty that the flywheel bolts are stock originals. In fact, the entire engine is from a TR4A, and the transmission may be too... Making it possible that they are TR4 flywheel and clutch.

TR4nut
12-16-2008, 01:43 PM
Not to get too offtrack, but be aware that a TR4A clutch&flywheel isn't the same as a TR3-4 clutch&flywheel. 4A has the diaphram style pressure plate & different mounting holes, 3&4 have the finger style. Not sure it would make any difference with the interference issue.

prb51
12-16-2008, 01:54 PM
Then that could be your issue if the bolts were too long.
All of the TR3/TR4 trannies are interchangeable as far as I know so shouldn't be a problem (since you have the app. engine etc). No experience with the latter stuff although you should have a synchro 1st gear with the latter unit.
Have you removed the tranny yet?

TR3driver
12-16-2008, 02:12 PM
Although there were 3 different flywheels, the bolts that hold them to the crank are basically identical. I'm not sure of the change point offhand, but the bolts did get very slightly shorter at some point, when the factory deleted the locktabs.

As noted, the 4A flywheel is drilled differently for the clutch plate. If you are using the 4A clutch & flywheel, you'll also need to shorten the front cover on the gearbox (otherwise the clutch fingers will hit it when the clutch is disengaged); and use a 4A style throw-out bearing.

Also worth noting that the original bolts were "specials", so you probably shouldn't be substituting hardware store stuff (even if that's what you found on your donor engine).

I have heard other stories of the flywheel bolts hitting the seal bolts when the locktabs are deleted with the early stock bolts. Not sure why that is, mine seemed to have plenty of clearance when I deleted the locktabs. Could be manufacturing tolerances, or possibly some subtle early/late casting differences. Possibly even some seal housings are thicker than others.

TR3driver
12-16-2008, 02:15 PM
All of the TR3/TR4 trannies are interchangeablePre-TS50000 boxes won't work with the later starter & flywheel; unless you cut a hole in the side or use an aftermarket gear-drive starter.

Not that that has anything to do with the problem at hand.

rlandrum
12-16-2008, 02:23 PM
Then that could be your issue if the bolts were too long.
All of the TR3/TR4 trannies are interchangeable as far as I know so shouldn't be a problem (since you have the app. engine etc). No experience with the latter stuff although you should have a synchro 1st gear with the latter unit.
Have you removed the tranny yet?

Yes. Tranny is out.

Someone above said that the bolts would need to be 3/16th to 1/4 too long. Peering down from the top of the engine, I'd guess the gap to be 3/16ths, and the bolts appear firmly pressed into the aluminum, suggesting they are not the "correct" bolts.

I'm not sure how to tell the difference between the different flywheels. But I'd bet good money it's a TR4 unit.

prb51
12-16-2008, 02:49 PM
I'm sure it is as there is no reason not to use the TR4 parts entotal, if the ring gear on the flywheel is a bolt on then it's a latter unit TR3a/b/4/4a. The early cars (like mine) had a press fit ring gear.
PITA to remove things but better now than latter and it's a simple fix, back them off and spin the motor by hand, you'll feel better.

Tinster
12-16-2008, 02:59 PM
I cannot say with absolute certainty that the flywheel bolts are stock originals. In fact, the entire engine is from a TR4A, and the transmission may be too... Making it possible that they are TR4 flywheel and clutch.


<span style="color: #990000">Randy- for what it's worth.

My TR6 has a TR250 long block, a TR4A clutch and
a TR4A tranny. Everything seems to fit together.

Here is a photo of the flywheel- hope it helps you.

dale </span>

https://i134.photobucket.com/albums/q101/TinsterTR6/flywheel2.jpg

TR3driver
12-16-2008, 03:47 PM
suggesting they are not the "correct" bolts. :iagree:

martx-5
12-16-2008, 04:46 PM
I installed a TR4A flywheel in my TR3 (HVDA conversion), and had no problem with the length of the original TR3 bolts. I did use locking tabs.

CraigLandrum
12-16-2008, 11:46 PM
My vote would be to grind them down. I might also suggest doing them one at a time - i.e. remove and grind one bolt, reinsert, torque, and repeat for the rest of the bolts.

For some strange reason I am finding it quite easy to resolve this issue from a distance :-)

My advice to you younger guys is to have kids early and often and when they are old enough, only buy them cars that need to be fixed up (i.e. cheap). That way they gain plenty of experience that will serve you well later in life :-)

My son is a saint, gents. Of course I've listed him as co-owner on the registration....

frank_fisher
12-17-2008, 02:26 AM
it is for sure the flywheel bolts.
my friend paul had the same problem.
then guess what? i did also.
we both fitted the new rubber rear oil seal with the new and obviously different alumium casting.
i reused my old bolts, not sure about paul's
we where both only about 0.015" too long. paul used split washers i used a very tight washer under the tab locks.
frank

TR4nut
12-17-2008, 09:00 AM
As was suggested before it does make me wonder if the housing for the oil seal is the primary culprit, particularly if the replacements are thicker than stock.

Randy

prb51
12-17-2008, 11:11 AM
R/Craig,
Did you gents mount the 'improved' crank seal unit?

rlandrum
12-17-2008, 11:30 AM
Yep... We used the aftermarket 1 piece oil seal. It was more work, but we wanted to ensure that it wasn't going to leak while it sat in one of our garages.

It required milling down the rear of the crank, then polishing it, then drilling two new oil galleys in the rear main cap.

I'd guess that the flange on the new aluminum seal is about 11/64ths, or just under 3/16ths. I'd also guess that the old one is 1/8th. But I'm going from memory alone.

prb51
12-17-2008, 12:24 PM
I'll be interested in how it works for you.
Could be a combo of the two..long bolts and thicker seal unit.
Looking at your Dad's signature block I'm surprised you're not working on a Heally.

angelfj1
12-17-2008, 12:35 PM
Rob: my 3A engine was rebuilt with a conventional rear seal and of course you know that I reported THIS problem back in Oct.

Don't take this the wrong way but don't you think it would be prudent to use brand new bolts and tab wahers? Just a suggestion.

Frank

prb51
12-17-2008, 01:35 PM
Frank,
I missed that thread.
When I put my flywheel back on I didn't even know there could be an issue and I didn't have any lock tabs so reused the original bolts with locktite.
I just looked at a friends rebuilt 3a motor and there is at least 3/16th clearance in that area if not more. The tabs are 1/8" or less which would still leave some room.
Now if someone had 'faced' the crank or flywheel mating area that could reduce the gap or improper thrust washers.
Did you originally have the bolts/tabs or the stretch bolts?
I'm sure the Landrums will replace the long bolts (they're not sure they are original anyway as to length) with the right stuff.
So the original bolts locked into the seal body?

rlandrum
12-17-2008, 02:06 PM
Don't take this the wrong way but don't you think it would be prudent to use brand new bolts and tab wahers? Just a suggestion.


In general, we have used new bolts and nuts everywhere.

However, the bolts used in the crank are not of the three standard sizes I have on hand (1/4, 5/16, 3/8, both course and fine). As I recall, they were 7/16. And they appeared in good enough condition to re-use without worry. Added to that is the fact that we were anxious to get the engine in the frame and the decision was made to make-do with the existing bolts.

Hindsight is always 20/20.

rlandrum
12-17-2008, 02:08 PM
Looking at your Dad's signature block I'm surprised you're not working on a Heally.

Me too, actually. When I found this car, the plan was to get it running for him, then let him sell it to a true Triumph enthusiast so that he could purchase a Heally. He decided this one was too nice to sell, I guess.

Of course, now we're Triumph enthusiasts.

prb51
12-17-2008, 03:22 PM
You guys are doing a great (and speedy) job on the TR3. Regardless as to it's final home you've saved another LBC for folks to enjoy.
I had a 100-6 in High School ( a real rat but it ran well) and also have a desire to acquire an early AH.
I'll keep the TR3 though, they really have a distinct personality and they are quick for an LBC.
I re use bolts all of the time...if I were racing etc. I'd be more replacement orriented.

PeterK
12-17-2008, 05:26 PM
Don't take this the wrong way but don't you think it would be prudent to use brand new bolts and tab wahers? Just a suggestion.


In general, we have used new bolts and nuts everywhere.

However, the bolts used in the crank are not of the three standard sizes I have on hand (1/4, 5/16, 3/8, both course and fine). As I recall, they were 7/16. And they appeared in good enough condition to re-use without worry. Added to that is the fact that we were anxious to get the engine in the frame and the decision was made to make-do with the existing bolts.

Hindsight is always 20/20.


Rob,

www.aptfast.com (https://www.aptfast.com) (800)278-3278 sells ARP and ships out pretty quickly. I paid under $20 for the set for my 4A. Worth it!

CraigLandrum
12-18-2008, 12:24 AM
FYI if I recall correctly my son had the crankshaft ground to accept the new type rear oil seal. He can confirm next time he's online. No clue if it makes any difference. Didn't get a chance to talk with him today so I don't know if he was able to resolve the issue with the bolts.

TR3driver
12-18-2008, 02:36 AM
Crank has to be ground to accept the lip type seal; but shouldn't have any effect on the bolt clearance.

IMO, just the wrong bolts. Maybe worked in the motor they came out of, but still longer than they should be.

glemon
12-18-2008, 10:19 AM
RE: Replacing nuts and bolts

I may fall on the other end of the extreme here, but I have owned and worked on british cars for all my driving life which is now over 30 years, for the first 15 or so they were my daily drivers. I have never raced, but have autocrossed, and though I have probably slowed down a little and tempered my driving enthusiasm over the years, I still take em to the redline and wind them out occasionally.

I re-use bolts and nuts unless they look to be stripped, corroded or otherwise damaged (or the more likely event where I can't find the ones I took off!). I have never had a major component fail or break due to a broken nut or bolt, when I rebuild things I replace the wear items, bushings and bearings. rubber parts, I am aware of the concept of metal fatigue, but also aware of defects in new parts, so somewhat of a crapshoot either way, if a stationery part has done its bit for 40 years or so and appears unharmed I sort of assume it is up to the task for a few more years.

To each his own, your mileage may vary, I don't fault people for doing it, but I for one I not so sure you have to do it.

My LBC dollars are not unmlimited and my car needs and wants many, I just don't choose to spend them that way, and quite frankly even if I had more $ probably wouldn't.

I guess I am just writing this as a counterpoint to the people suggesting all bolts be replaced--maybe it will put someone who didn't follow that advice's mind at ease that there motor is not likely to grenade the next time they turn the key. And certainly there may be instances where it is well documented that there is a weak point that needs a stronger piece on a particular car or motor, wouldn't ignore that, but just don't feel it is at all necessary as a matter of course.

rlandrum
12-18-2008, 11:28 AM
Got the clutch off last night and removed the four bolts. The engine turned with no problems. I installed lock washers (rather than tabs) and the engine still turns without interference from the bolts.

I should have the tranny re-installed tonight.

Thanks again for all the suggestions. They were all right on the money, as usual!

angelfj1
12-18-2008, 01:08 PM
Frank,
I missed that thread.
When I put my flywheel back on I didn't even know there could be an issue and I didn't have any lock tabs so reused the original bolts with locktite.
I just looked at a friends rebuilt 3a motor and there is at least 3/16th clearance in that area if not more. The tabs are 1/8" or less which would still leave some room.
Now if someone had 'faced' the crank or flywheel mating area that could reduce the gap or improper thrust washers.
Did you originally have the bolts/tabs or the stretch bolts?
I'm sure the Landrums will replace the long bolts (they're not sure they are original anyway as to length) with the right stuff.
So the original bolts locked into the seal body?

go here https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/507860/Re_Stuck_Engine_Help#Post507759
one of the bolts was just a bit too long.

angelfj1
12-18-2008, 01:09 PM
Don't take this the wrong way but don't you think it would be prudent to use brand new bolts and tab wahers? Just a suggestion.


In general, we have used new bolts and nuts everywhere.

However, the bolts used in the crank are not of the three standard sizes I have on hand (1/4, 5/16, 3/8, both course and fine). As I recall, they were 7/16. And they appeared in good enough condition to re-use without worry. Added to that is the fact that we were anxious to get the engine in the frame and the decision was made to make-do with the existing bolts.

Hindsight is always 20/20.


Rob: please use new bolts and tab locking washers. :yesnod:

TR3driver
12-18-2008, 01:51 PM
I re-use bolts and nuts unless they look to be stripped, corroded or otherwise damaged (or the more likely event where I can't find the ones I took off!).FWIW, I'm with you. The vast majority of fasteners in our cars are not stressed anywhere close to where metal fatigue becomes an issue. Plus in some cases the original fasteners were special in some way that might not be visible to the naked eye (or to aftermarket suppliers). Lacking the facilities to test for tensile strength or hardness or fatigue life, etc. I feel safer using factory hardware.

There are some things I replace frequently, like Nyloc nuts and lockwashers; but general bolts &amp; nuts get reused forever (unless damaged, of course).

BTW, the consensus among racers seems to be that it's a really bad idea to use lockwashers on flywheel bolts. I don't recall the exact argument offhand, but those guys have spent a lot of time trying to keep flywheels and cranks bolted together under the harshest possible conditions, so I suspect they know what they're talking about. ISTR Kas Kastner mentioned measuring over .600" (yes, over 1/2 inch!) deflection at the rim of the flywheel, so those bolts do lead a really hard life.

Supposedly, that's even why the factory eventually deleted the locktabs; as they are soft enough to eventually pound out and let the bolt loosen, even though it doesn't turn.

angelfj1
12-18-2008, 02:52 PM
I re-use bolts and nuts unless they look to be stripped, corroded or otherwise damaged (or the more likely event where I can't find the ones I took off!).FWIW, I'm with you. The vast majority of fasteners in our cars are not stressed anywhere close to where metal fatigue becomes an issue. Plus in some cases the original fasteners were special in some way that might not be visible to the naked eye (or to aftermarket suppliers). Lacking the facilities to test for tensile strength or hardness or fatigue life, etc. I feel safer using factory hardware.

There are some things I replace frequently, like Nyloc nuts and lockwashers; but general bolts &amp; nuts get reused forever (unless damaged, of course).

BTW, the consensus among racers seems to be that it's a really bad idea to use lockwashers on flywheel bolts. I don't recall the exact argument offhand, but those guys have spent a lot of time trying to keep flywheels and cranks bolted together under the harshest possible conditions, so I suspect they know what they're talking about. ISTR Kas Kastner mentioned measuring over .600" (yes, over 1/2 inch!) deflection at the rim of the flywheel, so those bolts do lead a really hard life.

Supposedly, that's even why the factory eventually deleted the locktabs; as they are soft enough to eventually pound out and let the bolt loosen, even though it doesn't turn.

Randall: I agree with you but I must add that any fastener that serves a critical function like internal engine and drive train or anything in constant motion and therefore constantly under cycling stresses should not be reused. Reusing these fasteners IMHO is unforgiveable and false economy. As far as Kas and his recommendations, remember that his primary goal was to improve reliability under race conditions. The bolts that are under discussion here are readily available from a number of sources, complete with locking tabs. Just be sure to measure the length. Of course I assume that Rob does not intend to race this car. :smile:

glemon
12-18-2008, 03:36 PM
Thanks to all for keeping the bolt discussion civil, I realize by disagreeing with others thoughts sometimes people can get worked up, just wanted to express a different point of view--not a criticism of other ideas and I hope it wasn't taken that way, we all want to make our cars as good as they can be given our own time and money restraints.

And of course discussing these very issues and letting others express their opinion and the Brit car world sharing useful information is what makes this forum "a good thing" as Martha Stewart would say.

And lastly, back directly on to the original topic--good news on the motor truning issue, an easy fix once identified, on to getting her back on the road, nothing like the trepidtion, and ultimately satisfaction, as you fire up the motor you took apart and rebuilt yourself.

prb51
12-18-2008, 03:44 PM
Rlandrum,
I'd not use lock washers with the flywheel as I've been told the same by others. Why not shorten them a bit and use locktite, that's what a friend that does race his car recommends in this case.
Pat

TR3driver
12-18-2008, 05:10 PM
Reusing these fasteners IMHO is unforgiveable and false economy.I guess we'll have to agree to disagree then, Frank. Even the engine with over 200,000 miles still has most of it's original internal fasteners, and has never suffered a fastener failure. And while I'm not a racer, I do drive hard ... it's seen 6000 rpm on occasion and spent hours in 4500+ territory.

Oh wait, I take that back, I did have a problem once from reusing a locktab. One of the very few times it came home on a flatbed. I don't use locktabs any more; new or otherwise.

rlandrum
12-18-2008, 05:31 PM
Once again, I may have goofed. I used grade 8 split lock washers to see if the clearance was correct, and it was. So I figured using them would mean that wouldn't have to 1.) buy new bolts, 2.) grind down existing bolts, or 3.) wait for locking tabs from moss (which might not provide enough clearance, actually).

I know that the "correct" thing to do is to use new ARP bolts, correctly (custom) sized, with Moss locking tabs and loctite. Is it therefore safe to assume that I have done the complete opposite of the correct thing by reusing my existing bolts with lock washers?

Basically what I'm asking is if my choice to use lock washers is ever likely to actually effect me. I really don't want to have to remove the clutch again. :smile:

PeterK
12-18-2008, 05:55 PM
Think of it this way: It is easier to r&amp;r now while the car is not completely together than later after it fails and the car is complete. Not saying that it will fail but when done right, the likelyhood of failure is reduced.

TR3driver
12-18-2008, 09:36 PM
Basically what I'm asking is if my choice to use lock washers is ever likely to actually effect me. I really don't want to have to remove the clutch again. :smile: I feel your pain, but ... if it were my car, I'd change the bolts. Especially since they don't appear to be the right bolts in the first place.

Removing the clutch is trivial compared to what's going to happen if that flywheel comes loose. It might never come loose, but I wouldn't risk it.