On 12/01/2022 12:51 am, Noddy wrote:
> On 11/01/2022 7:51 pm, Grumpy Tech wrote:
>> On 11/01/2022 6:35 pm, Xeno wrote:
>
>>> Yeah. Didn't understand the concept of valve *float* and valve
>>> *overshoot*, both circumstances that can lead to valve impact if
>>> insufficient clearance is allowed - and a thinner shim head gasket
>>> will take that clearance down by a *lot*. I didn't expect Darren to
>>> be able to do it but I did expect Daryl to know how it's done. He is
>>> *supposedly* qualified after all. Too much time pushing a broom I
>>> guess. Checking piston to valve clearance isn't rocket science by
>>> any means and there's plenty of info on the net for the uninitiated.
>>> But to fit a thinner head gasket and *not* check the clearance,
>>> that's nothing short of *criminal*.
>>> The funny thing is, I was expecting it to be a more esoteric cause,
>>> lean combustion, injectors at 100% duty cycle or MAF sensor pinning.
>>> I was overthinking it and not making sufficient allowance for the
>>> two clowns who were working on the 4AGE(20). I trust Les has learnt
>>> his lesson.
>>>
>> So it's his fault the engine failed even though he advised Les that
>> there were serious issues with the engine and failure was likely.
>
> Actually, it was *not* my fault that the engine died, and I'll go into
> some detail as to why that is to put this ridiculous bullshit claim of
> Clasener's to bed :)
>
>> I'm  guessing Les wanted to compete and went with the motor anyway as
>> availability of a replacement motor in a limited timeframe may have
>> been an issue.
>
> The issue with this engine was that Les was trying to build it on a
> budget, using parts from an engine that had already failed before I
> ever laid my hands on it.
>
>> Wouldn't be the first time someone has failed to take advice and it's
>> cost them dearly.
>
> No, but in fairness to Les and myself, the cause of this engine's
> demise had nothing to do with either of us. Well, at least certainly
> not me :)
>
> For those who don't know and who may be half interested in discovering
> the truth of this matter, the engine in question was a Toyota 4AGE 20
> valve, known as a "Gold Top" of I remember correctly, and this is the
> engine here:
>
>> https://www.imagebam.com/view/ME69PME
>
> It's a 1600cc 4 cylinder "high performance" engine that has a fairly
> high output for it's capacity and a healthy appetite for rpm, which
> Daryl's mate Les used to use in his Lotus 7 Replica for competition work:
>
>> https://www.imagebam.com/view/ME69Q3J
>
> Now, it's been Clasener's claim for a while that this engine died as a
> result of insufficient piston to valve clearance, and this is claim is
> absolutely fraudulent. It is a complete fabrication invented by
> Clasener for the sole purpose of having something to argue about. In
> reality, and as usual, he is *completely* wrong and has achieved
> nothing other than making a complete moron out of himself.
>
> Allow me to show how :)
>
> This engine was originally brought to me in around August of 2016
> after it had suffered a catastrophic failure. It actually broke a
> factory rod through the beam, which trashed the block and made a mess
> of the head, and damaged the crank and piston.
>
>> https://www.imagebam.com/view/ME69PTY
>> https://www.imagebam.com/view/ME69PU1
>> https://www.imagebam.com/view/ME69PU3
>> https://www.imagebam.com/view/ME69PU4
>> https://www.imagebam.com/view/ME69PU6
>
> This failure occurred before I had done any serious work on this
> engine, and in fact up until this point about all I had ever done to
> the engine was to fabricate a baffle for the oil pan and measure it's
> capacity while it was off, as the pan had been shortened to suit the
> chassis and it's oil level needed to be measured.
>
> Once this engine was dismantled Les set off to find a replacement
> engine, and the cylinder head was taken to his guys who had worked it
> before to repair the damage and make some new valves.
>
> Once all the parts were finally obtained they were delivered to me and
> my job was to assemble the engine, modify the windage tray and oil
> pick up to suit the oil pan, set the valve clearances and dial in the
> camshafts. Only parts of the replacement engine were used, principally
> the block and crank, as other parts from the old engine were still
> perfectly serviceable. The three surviving pistons from the old engine
> were retained as they were already oversize which allowed the new
> block to be bored to suit them, and a 4th piston was machined up from
> a semi finished blank to replace the one that was damaged from the old
> engine.
>
> New after market connecting rods were used, and despite the damage it
> suffered the original cylinder head was retained as it had already
> been subject to extensive port work and it was highly desirable for
> that not to be lost. The original camshafts were put back into service.
>
> The engine went together will with only a few niggles worth noting.
> The main one was that the person doing the bore and hone work was
> pretty average and their sizings were all over the place. The crank
> grind was perfect with exact sizes from front to rear, and the new
> rods were very good.
>
> This is the windage tray and oil pickup:
>
>> https://www.imagebam.com/view/ME69PLQ
>> https://www.imagebam.com/view/ME69PLR
>
> Normally this oil pickup would sit up about 3 inches higher than this,
> and the slot cut into the windage tray wouldn't be necessary. But
> because this engine sat so low in the chassis and didn't run a dry
> sump system it was necessary to bury this pickup as high up into the
> engine as possible so it would clear the modified oil pan, and it only
> cleared the crank web by about half an inch.  The brazing on the
> bottom of the pickup tube where it goes into the timing cover is were
> it was cut and shortened.
>
> Here, after final clearance checking, the short motor is assembled.
> Crank bolts triple torqued as per specifications and rod bolt tension
> set with a stretch gauge. Al the bottom end clearances were right down
> the middle which is exactly where I wanted them to be.
>
>> https://www.imagebam.com/view/ME69RAI
>
> Now we get to the juicy stuff which will show Clasener up as the shit
> talking clueless windbag that he is.
>
> Here's a few pics of the top of the engine and with the gasket in
> place before the head is finally ready to go on:
>
>> https://www.imagebam.com/view/ME69PLP
>> https://www.imagebam.com/view/ME69PLS
>> https://www.imagebam.com/view/ME69PLT
>
> Now, to the keen eye there's a few things to observe in these pics.
>
> In the first instance, you can see the three used pistons which were
> in excellent shape, and the one new one. Secondly, you can see the
> competition head gasket that was used, which is a compressible gasket
> and not a "shim" as Clasener incorrectly refers to it, and lastly you
> can see the remains of the pink plasticine that was used to check the
> pison to valve clearances on the exhaust valve releifs of the number
> one piston :)
>
> Inlet and exhaust clearances where checked on all four pistons which
> is standard procedure, and especially in an engine using non standard
> connecting rods, but residue of the plasticine only remained on the
> exhaust cut outs on the number one piston as they were a rough "as
> cast" finish where all the other surfaces were machined smooth. I
> wasn't all that fussed about cleaning it off as it would burn off the
> moment the engine was first fired :)
>
> Setting the valve clearances was the last major task:
>
>> https://www.imagebam.com/view/ME69PM9
>
> This is with the cams removed obviously, and the various markings on
> the head show where I'd been measuring clearances and swapping shims
> around to get within spec.
>
> The 4AEG engine uses a cam follower bucket system as can be seen, with
> the clearance adjustment shim being a small pad not much bigger in
> diameter than the valve stem that sits in a recessed pocket in the
> bottom of the bucket between the bucket and valve tip. The come in
> various thicknesses, but unless you have access to a great many of
> them setting the valve clearances on engines like these can be a pain.
> Especially when the people doing the cylinder head work aren't all
> that concerned about how much they cut out of the seat or they grind
> off the tip of the valve.
>
> It took an entire day to set the clearances using the limited
> assortment of shims that I had, and in the end I had to grind many of
> them on the surface grinder using a custom jig to hold them securely
> on the magnetic chuck.
>
> Finally, the clearances were set and the camshafts installed for good,
> and it was ready for it's timing belt and to be put back into the car.
>
>> https://www.imagebam.com/view/ME69S4W
>
> So, after all this long winded chest beating, what have we learned?
>
> What we've learned is that apart from a little bit of piston to bore
> clearance variation which Les was advised could lead to a bit of ring
> flutter and oil control problem, this engine went together well and
> had no clearance issues whatsoever. The engine was installed back into
> the car and test fired by me and it fired straight up with excellent
> oil pressure and had no temperature issues.
>
> At this point the car was handed back to Les were it was booked into a
> dyno session. It ran the dyno session successfully where it bed in
> nicely, and as Les was still playing with tune settings a second dyno
> session was booked not long after. Subsequently to this it did a full
> test and tune day at Winton raceway before it was packed onto it's
> trailer and taken to Bathurst for a class race meeting which was the
> ultimate purpose of having done all this work in the first place.
>
> And it was at Bathurst where things turned to shit.
>
> On the seventh Lap of Les's race, as he was coming through the Chase
> at the end of Conrod Straight, the engine had a change of exhaust note
> and blew a heavy plume of white smoke out of the exhaust. It was
> instantaneous, and it was abundantly clear that something in the
> engine had broken, and it's race meeting was over.
>
> Les returned to Melbourne and brought the car around for me to look at
> where he showed me the video of the failure taking place, and after
> pulling a plug and looking into the cylinder with a Borescope it was
> obvious that the engine had dropped a valve and suffered a terminal
> failure.
>
> I didn't do anything else to it, and Les went home with his tail
> between his legs and pulled the engine apart to see for himself. Once
> he did, he sent me these photos.
>
>> https://www.imagebam.com/view/ME69PMI
>> https://www.imagebam.com/view/ME69PMH
>
> What these pictures show is that an exhaust valve on number one
> cylinder has hit a piston, but moreover it did so while the valve was
> fully open at the limit of it's travel. That much is obvious from the
> fact that the valve was snapped off around half way up it's stem, and
> as the piston turned it sideways and tried to bury it into the seat
> pocket it caused the piston to rock in it's bore pushing it hard up
> against the cylinder wall and splitting it open.
>
> Anyone who has even the most "basic" of engine experience will tell
> you that this is most decidedly *not* the result of inadequate piston
> to valve clearance :)
>
> In the case of piston to valve clearance issues, you mostly see it on
> inlet valves as with big overlap cams like this engine ran the inlet
> valve begins opening very early while the piston is still moving up
> the bore towards top dead centre. As the two are moving towards each
> other interference can occur if clearances are not where they're
> supposed to be. In the case of exhaust valves it's a different story
> as the exhaust valve is moving *away* from the piston as the piston
> nears top dead centre, and as a result piston to valve contact with
> exhaust valves is quite rare. Not impossible, but certainly far less
> likely than it can be with inlet valves.
>
> However in either case the net result is usually the same in that
> unless you have things stupidly wrong about the most you'll ever see
> happen in the case of piston to valve contact near the very end
> (exhaust) or very beginning (inlet) of the valve's period is for the
> valve to bend slightly just behind the head, which will result in the
> valve no longer sealing against it's seat resulting in a loss of
> compression in that cylinder.
>
> And that is *not* what happened in the case of Les's engine.
>
> In Les's case the exhaust valve came into contact with the piston
> while the valve was at or near the fully open position, and there is
> basically only two ways for that to occur. Either the valve grabbed in
> it's guide, or it "dropped" into the cylinder after losing a collet or
> had a collet groove failure which unloaded the valve spring. I never
> got to see the remains of the top half of the valve so I can't tell
> you exactly, and while I wasn't at the track to see where Les was
> running his mixtures and have no idea how hot it was getting I'd
> happily bet that Les was running the thing fairly conservatively given
> that he had a habit of doing so and was familiar with the setup of the
> vehicle. Either the valve guide clearance was too tight or the valve
> failed prematurely, but either way given that I had nothing to do with
> the head it had nothing to do with me.
>
> Some important points to bear in mind here are that a piston to valve
> clearance issue is a mechanical issue that is evident from the first
> time the engine is turned over in extreme cases, and certainly from
> the first time the engine reaches operating temperature in borderline
> cases. However in *all* cases it is *not* a problem that will suddenly
> magically appear after an engine has done some time at full noise like
> this one did, and if Clasener and and his clog wearing puppy dog had
> *any* idea at all they would *know* this.
>
> But apparently they did not. Or they did and ignored it and just
> invented whatever bullshit story they wanted to crow about, because
> hey it's not like they've never done that before, right?
>
> These people are fucking *imbeciles* who would be incapable of holding
> down a job for more than a day in any decent workshop where you had to
> reply on your skills and knowledge to get by....
>
>> You really need to get over your obsession with abusing Noddy. You're
>> not perfect yourself and anyone who saw the tractor split would agree.
>
> "Not perfect" is being extremely generous. Completely clueless would
> be more accurate.
>
>

nice pictures. now how about some of your trade qualifications? or
forever be considered a liar.

--
"his opinions have been crushed into insignificant dust by
the enormous weight of his lies"- Alvey on the Fraudster