What to check/prep on an unknown engine ?

[JohnD]

Colin makes a good point, but risk analysis says that even a rare ocurence that has major consequences should be taken seriously.   You don't point a gun at anyone, even if it is known to be unloaded, as a tragic filming incident showed last year.

At the same time, we all take risks, because we do calculate them, thus

(probability x consequnce)                                                 need.

  When the result is low enough so as not to be of concern, we go ahead.   

Larger bolts may be the way to a lower probability of failure, egret.   I'd recommend more bolts!

John

 

 

Edited January 2, 2024 by JohnD

[Escadrille Ecosse]

6 minutes ago, egret said:

The flywheel has a races which locates on the crankshaft, rotational orientation is set with a dowel pin, so the bolts are there to keep is all together and provide the friction to resist the torque rotation from engine power and rpm changes.

I'm happy what I'm doing will be ok for now, it'll have a very careful assembly, some loctite, and proper torque.

This leaves the 1300 flywheel ready for some machining as/when I have the money and when I take the engine out again to balance the bottom end. Given some of the points here I might even get the crank machined for larger bolts too.

Yup ... 

 

[Escadrille Ecosse]

37 minutes ago, JohnD said:

Colin makes a good point, but risk analysis says that even a rare ocurencevthatbhas major consequences should be taken seriously.   You don't point a gun at anyone, even if it is known to be unloaded.

At the same time, we all take risks, because we do calculate them, (probability x consequnce)/need.   When the result is low enough so as not to be of concern, we go ahead.   

Larger bolts may be the way to a lower probability of failure, egret.   I'd recommend more bolts!

John

John. Stop.

Why are you picking on Egret?

You race Silverback. It has a flywheel. So does everyone on Sideways with a car, even if we don't race our cars we generally drive them in a 'spirited' fashion from time to time. Are you suggestion that the probability x consequence of an unanticipated flywheel failure is such that we all need to modify our cars with more/bigger flywheel bolts to avoid the real possibility of a disintegrating flywheel? Will you be doing that now the subject has been raised?

Bolting is a technical engineering subject. Simply putting in bigger bolts without doing anything else won't generally make anything better and may make things worse. Bolt tension is what matters for keeping things together. The size and number of bolts used is a result of getting the correct tension for a dynamic application, not the other way round.

And more bolts make more holes in the things you're worried about being strong enough.

Egret is fine. As are we all in this respect I'm sure. I'm certainly happy with my small bolts in my 1300

 

Edited January 2, 2024 by Escadrille Ecosse

[egret]

Don't worry, I'm not feeling picked on at all.  I'm confident what I'll be assembling will be solid.  I'm accutely aware of where the flywheel sits in relation to my legs given the tunnel is out, so I'm not making rash decisions here!

[JohnD]

Oh, dear!  I wasn't picking on anyone!  Although the mention of  a loose, clattering flywheel above filled me with dread.

Yes, I raced Silverback, as I race its successor, SofS (Son of..).  Racing, any competition, stresses to the limit and I've always tried to bear that in mind.   I like to think that saved my life when I totalled Silverback - I had built it strongly enough! 

We are all engineers, some of us proper ones! While it was one of the best engineers ever that said, "Just add lightness", us lesser mortals should be more cautious!

[Hamish]

I’m noooo engineer May be a fair spanner jockey. But I was happy to go with engine builders approach of a modern light weight flywheel. Or is it a starter ring and clutch carrier at 5kg

rather than the heavily machined original cast jobbie all spinning at 6k+
 

driving is a risk nowadays racing less so we do what we can to minimise the risk.  
a well pegged and bolted flywheel will be fine. There is s all the other stuff to worry about. 

[egret]

The trigger wheel locating system has been made.  There is an aluminium spacer to prevent the steel pulley diluting the vr sensor signal, then a locking ring to allow fixing of the trigger wheel and setting up the timing. I'm waiting for hex head bolts so I can adjust it when in situe, but it's made. The inserts for the flywheel, and a new end to my clutch alignment tool have been made. I think dad's had a busy, but fun week, and his newly styled "impington engineering services" have done a great job!

I think I now have all the bits so I can get back on with reassembly.

If people are interested I can go into more detail on the trigger wheel attachment.

[JohnD]

Egret,

From experience, there is not enough clearance behind the pulley wheel for the trigger wheel AND nuts on studs.   I have found that even bolt heads foul the timing cover, and have used countersunk screws.

John

[Escadrille Ecosse]

John, there's a lot more space behind the pulley on the early 4 cylinder cars because the back is conical as Egret's sketch.

On mine I fitted the trigger wheel right at the bottom of the cone section. So even closer to the engine than Egret's.

Nice and simple for making a bracket to fit the sensor too. Front/back with a slot. In/out with spacers.

and it fits just fine on the front of the engine.

[JohnD]

Thank you, Colin!  Apologies, egret!

Mine caused me great angst when I first started it.  The noise was awful, as they just scraped the cover.

JOhn

[egret]

Just been out to check (perks of working from home). Plenty of space, should work with my simple angle bracket which I'll bolt onto the front plate.

[Escadrille Ecosse]

8 minutes ago, egret said:

Just been out to check (perks of working from home). Plenty of space, should work with my simple angle bracket which I'll bolt onto the front plate.

Knew it would... been there

Regards the bracket, either use the existing bolt holes in the flange or weld a mounting to the cover to bolt to. Don't put holes in the cover as they will leak.

I know everyone else will disagree on this point but I found welding the mounting on a lot simpler than trying to make up a rigid enough bracket to work off the existing bolt holes. A lot neater too. Never seen a Triumph installation do this although lots of others have done so successfully so I don't expect much support on that front but there you go

[egret]

I'll bolt it to the front plate outside of the engine, so no worries about oil leakage.  It's not that easy to get to with the exhaust manifold in the way, but it's pretty much fit and forget.

Not a great photo from the previous installation, but exemplifies the plan.

[Escadrille Ecosse]

2 minutes ago, egret said:

I'll bolt it to the front plate outside of the engine, so no worries about oil leakage.  It's not that easy to get to with the exhaust manifold in the way, but it's pretty much fit and forget.

Not a great photo from the previous installation, but exemplifies the plan.

Yes. Forgot you already had this in the bag

[egret]

Don't worry I hope this will be useful as documenting the process for others.  Probabyl useful for me too as I've certainly revisited some of my old threads in the past to reaquaint myself with what I was thinking at the time!

By drilling the front plate it means I don't need to weld, something for which I currently lack the resources and skill!

[egret]

Quick question. I'm about to install the head and I've noticed there is a slight burr on the combustion chamber recesses where the edge is perpendicular to the head face. I feel like these edges will be potential hot spots. Should I take a deburring tool to it to chamfer them slightly or is this not something to worry about?

[Nick Jones]

Yes, I would remove any burrs and/or sharp edges from the chamber. Don’t need to take off much - a fine file will usually suffice 

[Escadrille Ecosse]

This ^^^^^

[egret]

D'oh of course. I must be more tired than I realise and have a bit of tunnel vision. Of course a file will work, I've got a set of needle files that will be absolutely perfect. I'd got it into my head I needed one of those jiggley deburring tools

 

Thank you, I might get the head torqued up tonight and see if I can't get the engine lifted back in tomorrow.

[egret]

Some good progress. Still a very long list of things to do, but the engine and gearbox are back in.  The head's not torqued up and I'm about to review the 3 sets of rockers I have to pick the best set.

I'm very much in to the phase of reassembly. Starting to see the path to firing it up again.

[egret]

Well, it's almost all back together.  Just missing the transmission tunnel and interior bits really.  It turned over nicely and cranks about 65-70psi oil pressure on the gauge I fitted (a hand me down from my father's mk 2 from before I was born).  So far it only stumbles but won't actually run, but I didn't try all that long.  Carbs are providing fuel, and it is most lively at full choke, but the plugs are wet. I'm slightly suspicious of the megajolt. Given that it needs the wiring and mounting sorting anyway, my plan is to try and neaten that all up slightly and check/trace the wirong before trying again.  This time with a second pair of eyes to help with checking spark etc.

Oh and I need a new belt. Not sure why but the three I have are all different lengths and only the shortest fits, but only in such a way that you can barely get to spark plug 1.

[JohnD]

Please keep posting on your progress,  egret!     My experiment on Megajolt failed ad I'd like to try again!

[egret]

I'll keep on with the updates.  There were several sidetracks on the way to getting it ready to turn over this weekend:

The fuel pump.  The fueling system was set up for the later type with 8mm fuel hose, whereas the pump from the 1300 is set up for 6mm.  I had an 8-6mm reducer where it entered the carb float chamber, but have used that on the 8mm copper pipe from the back fo the car.  With a 6mm-6mm brass adapter machined up byb dad I've replaced the fuel line from the copper tube in under the car in all R9 6mm rubber tube.  I didn't want to re-us e the 1500 fuel pump was a recent replacement and seems to have worn through the hardening and I'm pretty sure has scrapped the 1500's camshaft!

The altenator.  The pulley is smaller on the 1300 and given that the 1500 one was one I bought new and the 1300 one was unknown I decided to use the new one.  Neither unit gave up their pulley without a fight.  I snapped a mounting ear from the 1300 one when attempting to loosten the nut :(.  The 1300 one had a keyway, the newer one does not.  I manage to torque it up with an impact driver (18V diy one, not a proper one), so I've marked up the rotation with tippex and will kepp an eye to check it isn't moving.

The fan thermostat.  The capilliary tube shorted out on something and appears to have fried itself.  My fault and I'm a little bit cross with myself.  Hopefully not done any further damage, but this is one reason why I'm not progressing too much today and will check over the megajolt over the next week.

So still plenty to do, but it feels like it's close to driving, and there have been various little improvements and restorations along the line of this dismantling so I'm really excited to get it back driving.  The goal is to get it driving by next weekend to use as transport to get to a track day (not driving the spitfire) with my brother.  Maybe when the engine is run in, and I've got the oil cooler fitted I'll take on the track.

[Nick Jones]

Good to know there is progress happening 

I didn’t think the large crank pulleys fit the small crank engines? Not keen on no keyway either…. That will move unless done up really tight.

That pump lobe ……. WTF?!!

Is that a factory or aftermarket cam? Could it have been a pump intended for use with a spacer fitted without a spacer? Though that usually breaks the pump….
You can always use an electric pump.

[JumpingFrog]

I've also got a cam with a pump lobe identical to that in an engine I bought. My suspicions are the same as Nick's - running without the spacer, but as the seller of the engine kept the pump, I have no evidence to prove it. Fully agree with him on the recommendation of the electric pump, I've messed around enough now to know it's the best solution.

As for the alternator pulley, I'm not sure it's that critical. But there are calculators online for it (http://www.wallaceracing.com/calc-alternator-rpm.php). The worst case is the 1500 one will just spin a little too fast and waste energy. IIRC ideal pulley size is something like 60mm but it's not a common size (at least for a Lucas A127). I'm not sure Triumph ever fitted an alternator to the small crank engine? So maybe your 1300 alternator doesn't have the right pulley to begin with?

Looking forward to more updates!

Edited January 15, 2024 by JumpingFrog