Jul 052016
 

The joy of finally having the hood completed was short lived. I had hoped for at least a reasonable period of trouble free motoring. Alas, as the speedo had packed up on the way to the trimmers, I now found myself having to take things apart and rather urgently. Its 2nd MOT is overdue.

There are two issues to address; firstly to investigate why the wretched thing has stopped working and secondly to have it re-calibrated. It was reading a mere 56mph whilst following a lead car travelling at 70mph – 20% too low. The suggestion from the E-Type forum was to send it to Speedograph Richfield for the recalibration. So that left just tracing why it had stopped working.

The cable was detached from the back of the speedo in order to see whether the inner cable was rotating whilst driving. It was not. So this pointed to issues at the gearbox end. Most likely a failed angle drive, which is a known weak spot if everything isn’t operating smoothly. I didn’t want to contemplate if that wasn’t the cause. The only other option would be the speedo driven gear, which would require the engine & gearbox to be removed due to the lack of clearance.

Location of angle drive. Unfortunately the trim
had been put back in place since this was taken
A faulty speedo driven gear needs engine &
gearbox removal, as it’s removed sideways

Even so, accessing the angle drive is not easy, let alone getting it off once you have! The transmission tunnel is so close, the gearbox needs to be levered to the left side in order to withdraw the angle drive. The two options are from above, removing the seats, radio & centre consoles and gearbox cover or attack it from underneath.

It was almost possible to get at the angle drive from below with a very small pair of mole grips when the rear was raised on ramps. However the grip’s handle impacted the gearbox mount. At least it confirmed that it should be possible from below.


Exhaust was lowered to gain
access to the angle drive

The plan hatched was to lower the exhaust by undoing the mountings rear of the front downpipes rather than removing this whole section of the exhaust. The gearbox would be supported in order to remove the gearbox mounting.

In my haste I’d completely taken leave of my senses. Even though I had supported the gearbox, I’d forgotten that the supporting spring in the gearbox mounting was still under considerable compression.

I merrily set about undoing all the rear mounting bolts a bit at a time. As soon as the third of the five bolts was removed, the spring suddenly ‘let go’ with an almighty bang, pressing the gearbox mounting against the bodywork on one side and the dropped exhaust on the other.

Fortunately there was no damage but it was quite a shock and I was cursing myself for not reading the manual first! By trying to cut corners and not remove the rear exhaust section, I had created another issue. I now had to find a way of pushing the rear mount back into position in order to remove the last two bolts. However the exhaust was in the way and was now supporting one side of the rear mount that had been pushed down by the spring.

By chance I found a thin block of metal which fitted in the narrow gap between the silencers, enabling the bracket to be jacked back into position. Phew, but it was a nervous time removing the last two bolts. The angle drive was then unscrewed with mole grips and removed, while levering the gearbox over a few millimetres with a short length of 2″x4″.

Supporting the gearbox while
trying to jack the gearbox mount
to compress the support spring
The driven shaft from the gearbox had
been pulled out of the faulty angle drive
Note: round shaft, squared at one end

On initial inspection the angle drive did appear to be broken. The square shaft that engages with the driven gear in the gearbox was detached from the angle drive. Although this could have been caused during removal. This shaft looks a though it is made from a very tightly coiled wire which gives it some flexibility and is squared off at the output end. The internal end is left rounded and is simply held in place by an interference fit and it was this that had failed.

SNG Barratt didn’t have any in stock and wouldn’t for several weeks. So I called Speedograph Richfield to see if they had any available. They didn’t but during this conversation I found out that not all angle drives are equal. The correct one for E-Types has a ratio of 1:1.27. Other makes and some other Jaguar models had a 1:1 ratio. Externally they are identical so I needed to make sure I sourced the correct ratio.

Searches on angle drives in the E-Type Forum confirmed the variations. Hmmm …. could it be the angle drive causing the low speedo readings rather than my speedo needing to be re-calibrated? The test reading of 56mph multiplied by a ratio of 1.27 gives 71mph. Too close to the speed indicated in the lead car to be a coincidence.

Sure enough, the ratio of the old drive was found to be 1:1. A rolled up Post-It had been inserted into the old angle drive to check the rotation of the output drive for one revolution of the input shaft. The same test was repeated on the new angle drive to confirm a correct 1:1.27 ratio before it was installed on the car. The replacement angle drive had a shorter drive shaft so it should be easier to fit as it won’t require the same amount of clearance.

Checking the ratio of
old angle drive
Exercise repeated for new
drive before fitting
Newer drives have shorter shaft
– much easier to fit!

I still hadn’t got to the bottom of why the old angle drive had failed. Did it just fail or was it caused by other components? The cable was removed from the car and all appeared to be in order. There were no kinks and it was operating reasonably smoothly by hand.

It was a good opportunity to clean and re-lubricate the cable and the inside of the sheath. I wiped the cable with some silicone lubricant as some advised that grease can cause binding problems further down the line. Grease or oil will also have a tendency to migrate up the spinning cable which acts as an Archimedes screw, potentially causing damage to the speedo itself.

The cable was reattached to the speedo to check it could still rotate freely and not bind. It couldn’t be turned at all! The speedo’s input drive had seized. This explains why the weakest link in the chain had failed – the interference fit of the round shaft into the angle drive.

The conclusion is the seizure in the speedo would have stopped the cable from rotating. This in turn would have stopped the output of the angle drive from rotating. With the angle drive locked and the input shaft still being driven from the gearbox, the round end of the input shaft would have failed rather than the square end.

With the cause identified, the new angle drive and cable could be fitted back on the car. The exhaust was removed first so the gearbox mounting bracket could be easily jacked into position. It was also a good opportunity to finally fix my wonky tail pipes.

Something I should had done at
the outset – remove the exhaust!
Access to the gearbox mounting
bracket is much easier
Jacking the mounting bracket
into position to fit the bolts

All the instruments and gauges had been professionally restored many years ago and safely put in storage until needed. So I was rather disappointed the speedo had failed after only 500 miles. It will now have to been sent off for repair.

The input drive into the speedo performs two tasks; i) driving the needle and ii) driving the odometer/trip distances. At the internal end of the input shaft is a worm drive and an input disc containing permanent magnets.

The worm drive simply rotates another gear wheel which then drives gears for both the odometer and trip distance mechanisms.

In close proximity to the input disc is a similar sprung disc containing magnets to which the speedo needle is attached. As the input disc starts to turn, its magnets attract those on the needle disc causing it to turn. The faster the input disc rotates, the greater the torque on the needle disc due to the magnetic attraction.

Brass worm gear turns nylon gear
that drives odometer/trip distance
Input disc rotates within the
needle disc

A hairspring on the needle disc counters this rotational force, stopping the needle disc from free wheeling. The amount the hairspring coils is proportional to the rotational force and therefore road speed.

Speedograph Richfield can either calibrate the speedo back to the factory settings or calibrate it to your specific vehicle. I’m fairly sure the new angle drive will resolve the fact that it was reading 20% too low and so the factory settings would be fine. However I’ve also provided the measurements for it to be calibrated to the car, so they can determine if there is a discrepancy between the two.

To do this, they need to know the type of tyres in order to calculate the rolling circumference and the number of revolutions of the speedo cable for 6 revolutions of the driven wheel. The tyres were checked to ensure they were the correct pressures and a chalk line put on the rear tyre to aid measuring exactly revolutions.

To help count the revolutions of the speedo cable, I cobbled together a pointer made from matchsticks which slid onto the square end of the cable. All very high tech! The car was pushed forward with one person counting the wheel revolutions and the other the cable pointer. The average of three measurements was 8 full turns and 290 degrees (+/- 5 degrees) for six revolutions of the rear tyre.

Mark to accurately a full revolution My matchstick speedo cable pointer!

It is now with Speedograph Richfield who have indicated it should be returned within the week. A pretty good turn around. So fingers crossed this will be the end of my speeding troubles.

Sep 292015
 

Progress has been slow of late and the finishing line still feels some way off. I’m still waiting for the trimmers to have a slot to fit the hood and some of the outstanding internal trim. At least the enforced delay would allow some teething problems to be addressed. The most pressing being issues with clearance of the gear lever and gear selection.


Removing gear lever gaiter
revealed lack of clearance
with the gearbox cover

Something was seriously amiss with the positioning of the gear lever in relation to the central console. The lever was too far back making it difficult selecting either 2nd or 4th. Even once selected, the convoluted rubber gaiter was being compressed against the console, resulting in a tendency to pop out of gear into neutral.

The console couldn’t be moved rearward as it was already in contact with the rear bulkhead. Likewise there’s no adjustment in the positioning of the lever so it couldn’t be moved forward. The only option would be to undo the engine mounts and stabiliser to prise the whole transmission forward, but this would only gain a millimetre or two at best.

I’d been forced to remove the centre console in order to drive the car, which allowed me to swap over the rubber gaiter to one used on the later v12 models. The bulbous, convoluted design had been changed to be more slim-line. Several members of the E-Type forum had suggested using the later design to alleviate minor clearance issues with the centre console. Although I wouldn’t consider the lever impacting the metal gearbox cover as minor!

Convoluted S2 gaiter versus
slim-line V12 gaiter
The gaiter is secured to the
gearbox cover by a clamping ring
V12 gaiter is more suited
to the shape of the console

At this point I just happened to notice the mounting of the gear lever mechanism differed from the diagram in the parts catalogue. The company chosen to recondition the gearbox had missed out some fibrous Tufnol washers and mounted the main spring washer on the wrong side of the gearbox lid!

Repositioning the spring washer to its intended location gained around 8mm of clearance and, with the addition of the Tufnol washers, removed all the free play in the gear lever action. Much better! It should be sufficient to stop popping out of 2nd & 4th once the central console is refitted.

Parts manual shows correct
location of spring washer
Incorrect location
between jaw and lid
Lever mechanism components
(now including missing washers!)

Although the clearance problem was just masking a potentially more serious issue. More often than not, changing down into 2nd gear would result in awful graunching. It was fine double de-clutching so I suspected there might be an issue with the synchromesh. I was trying to kid myself that the reconditioned gearbox just need ‘bedding in’ simply because I just couldn’t contemplate having to fix an internal gearbox issue!


Synchromesh relies on friction
between the two cone surfaces

However, from my limited knowledge of gearboxes, it uses standard interference fit synchromeshes which helps engagement by matching the speed of the chosen gear to that of the output shaft.

Therefore a gearbox with a new synchromesh would have ample friction. Graunching would point to a lack of friction and the need to replace the synchromeshes.

It was time for a second opinion so again I turned to John and Martin who’d installed the IRS many moons ago. Their advice was to perform some investigative tests; first to rule out the clutch disengagement, which might result in similar symptoms, and the second to check the action of each synchromesh to confirm which, if any, were the route of the problem.

I hadn’t considered the clutch but if it wasn’t disengaging properly, the layshaft and gears would still be driven by the engine and the synchro would be acting as the clutch. Therefore likely to produce graunching, although I guess in all gears.

The suggested test to rule out a disengagement issue was to depress the clutch, with the hand and foot brakes off. Wait for around 10 seconds to allow the layshaft and gears to stop spinning and then select a gear. If the clutch wasn’t fully disengaging, the gears would still be spinning and the car would show signs of wanting to pull away.

On the positive side, the outcome was that the clutch was operating correctly. Although it was therefore pointing more to a dreaded synchromesh problem. Their next tests were of a similar nature, depressing the clutch from neutral. However rather than waiting to allow the gears to stop spinning, the gear lever was pushed immediately and firmly into the chosen gear without any wait. This would be done for each gear, selecting with both a fast and delayed lever push.

The theory being that a worn synchro would not develop sufficient friction with the selected gear to enable their speeds to be matched before their dog teeth engaged. The faster the action the less time there would be to synchronise the speeds.

The test should be repeated several times for each gear, doing a full ‘re-set’ each time (from neutral and clutch up), to see if a pattern emerged. If the synchros were working correctly there wouldn’t graunching on either the fast or delayed action. A suspect synchro, in my case 2nd, would graunch in the ‘no-delay’ fast instances and possibly on the delayed selection.


A run in the car without the cover
revealed the cause of the problem
(note – relocated spring washer)

I was very relieved that no graunching was evident in any gear, for either action. Perhaps it wasn’t an internal gearbox problem after all, which would require an engine out fix. I took the opportunity to take the car for a spin, while the gearbox cover was off, so I could see the selection mechanism at work in more realistic road conditions.

What I observed surprised me and explained the graunching that I’d been misdiagnosing as a synchromesh problem. The corrections in the lever mechanism had made subtle changes to the geometry by moving the lever directly over the quite narrow 1st/2nd selection rod. Previously it had been at a slight angle so the lever could also catch the reverse selection rod at the same time.

More importantly the reason for the graunching was actually caused by selecting reverse gear instead of 2nd!! A sprung plunger is used to avoid accidentally selecting reverse while using the forward gears. However the resistance it offered was so weak it was quite easy to go beyond 2nd all the way into reverse without realising.

Gearbox lid removed to check
selector rod operation
Selector arrangement and
reverse plunger & adjustment

A sprung ball bearing presses into a groove in the plunger to create the resistance and can be adjusted via a setscrew. Even so, for a given setting, there was a noticeable difference in the effort required to depress the plunger depending on whether the lever was starting in the 1st/2nd or 3rd/4rd planes in the gate. This was simply due to momentum, with less effort required from the 3rd/4th side of the gate.

I opted to set the desired resistance from this position which should minimise the frequency of accidentally selecting reverse while changing down from 3rd to 2nd. The compromise is that it needs a good shove to select reverse when the lever is in the 1st/2nd plane, but this would typically be while stationary.

It was a great relief to get to the bottom of the gearbox problems although the only slight niggle is occasionally not being able to engage 3rd from 2nd. The 1st/2nd selection rod doesn’t always quite reach its neutral position but allows the lever to cross the gate for 3rd. As it hasn’t reached neutral, the interlock is doing its job and prevents another gear being engaged, in this case 3rd.

If baulking occurs going from 2nd to 3rd, the lever must be returned to the 1st/2nd plane to ensure its knocked into neutral before going for 3rd again. I took the top of the gearbox off to see if the ‘O’ rings were causing too much resistance in the movement of the 1st/2nd selection rod for the detent to pull/hold it in neutral. But all seemed in order.

It appears that this is not uncommon and can be avoided by a more sympathetic gear changing technique using light finger pressure and ‘palming’ the lever to guide it. I had been changing from 2nd to 3rd by applying a constant forward and sideways force rather than three distinct movements.

The double de-clutching I had used to overcome the graunching, adding weight to my synchromesh diagnosis, had worked simply because it changed my technique of changing gears. Therefore avoiding accidentally selecting reverse.

Fingers crossed this will be the end of the gearbox issues!!

Sep 192013
 

It has only been just under a month since the rear suspension was put in, in which time the weather has started to turn, with leaves falling and a persistent dampness on the ground. The hope was to recruit John and Martin again to put the engine back in and set up the front suspension. However doubts started to creep in whether a leave of absence would be forthcoming from their higher authorities.

Still we pencilled in the last weekend in September for the engine install just in case permission was granted! It was the last free weekend before the clocks change but the problem would be if the weather wasn’t favourable on the day. The next available weekend would not be until early December.

I decided it might be better to go it alone earlier, on the next fine day, but keeping the September weekend as a reserve. So the BBC weather forecasts were monitored for a suitable, sunny day. A whole day with only light cloud cover and sunny spells was forecast, so last minute arrangements were made to have a days leave to finally install the engine and front suspension.

The original plan was to remove the front ‘picture frame’ and simply wheel the engine into place and then refit the frame behind it. I should know by now that nothing is ‘simple’ when rebuilding an E-Type! As the rear suspension had taken all day and we’d run out of time, the revised plan was to install the engine from below. The same way it had been removed.

At least this time, the engine was on a low trolley so the front of car wouldn’t have to be raised quite as much to gain the necessary clearance. The positioning of the engine within the frames went without a hitch and the trolley castors made fine adjustments in its position a breeze.

Although there was almost a numpty moment as the engine was being rolled into position – it generally helps to have the propshaft fitted before the engine goes in!!

The car was then lowered until the front fulcrum mounts could be supported on axle stands, enabling the lifting frame to be moved and redeployed to lift the engine on to its mounts. The clearances around the bellhousing are quite small, especially round the torsion bar mounting points, so the lowering progressed very slowly to ensure the paintwork wasn’t damaged.

Lifting the engine was an equally slow process for the same reason. It was also very marginal whether the lifting frame would have sufficient height due to generous length of the lift strop. Fortunately there was, but only by a centimetre. It would have been possible to shorten it by putting a knot in but I suspect it wouldn’t have come undone once the full weight of the engine had pulled it tight.

The gearbox mounting bracket and damping spring, which sits in two rubber mouldingsI had wrongly assumed that once the mounting brackets had been fitted to the engine, the weight would naturally align their bolt holes with the engine mounts fixed to the frames. After a considerable struggle, not dissimilar to the fitting of the rear suspension, everything was lined up and the front engine mounts could be secured.

A strong spring sits between the gearbox and the rear mounting bracket to dampen the vibrations of the engine. Fortunately is was only a matter of jacking up the bracket to compress the spring sufficiently to get the bolts in place. Although some care was taken to make sure the spring was located centrally on the trolley jack.

There’s very little room to get in to fix the engine stabiliser so it’s a fiddly jobI thought it would be easier to fit the central engine stabiliser once the engine was in place, as it’s one thing less to keep an eye on when the engine is lifted. It’s was fiddly job as there’s very little room between the engine and the bulkhead to get your fingers in. I think I’d prefit it next time.

Once again the progress was considerably slower than hoped although this was partly due to the accuracy of BBC weather forecasting – light drizzle and grey skies were the order of the day. As dusk approached, the installation of the torsion bars was abandoned for now.

The radiator and cooling fans had already been built up so these were quickly bolted on before the bonnet was refitted. It was time to wheel it inside and head off to the pub for a celebratory meal …. so it wasn’t the best time to find out that the bonnet no longer closed. Something was stopping it about 2 inches short of the landing rubber.

It wasn’t a solid contact you’d get between two hard objects. It was more springy. Some of the wiring looms still had to be re-routed so these were moved well out of the way. Still no joy. The problem is that is almost impossible to see into the engine space when the bonnet is almost full closed.

It can only be one of two things as the engine and radiator were the only items fitted but at the moment I’m stumped. Some padding has been inserted between the bonnet and bulkhead until I can it work out!!

Reuniting the engine and gearbox

 Rolling Chassis, Transmission  Comments Off on Reuniting the engine and gearbox
Jul 082013
 

My aim is to spend a long weekend in August (with the wishful thinking that it’ll be sunny!) to transform it from a bodyshell into a rolling chassis; installing the fuel system, rear suspension, engine/gearbox & ancillaries, front suspension and steering all in one hit. So I’ve got my work cut out to get everything ready in time.

The bonnet and front sub-frame need to be removed in order to fit the tiny radiator support brackets so I’m also going to remove the picture frame at the same time. It should then be possible to roll the engine and gearbox unit into place through the gap and avoid the hassles of installing the engine either from above or below.

The gap between the lobes at the lower front edge of the engine frames is only 22cm. However, if the water pump is removed, the engine is slightly narrower than this just below the height of the inlet manifold. The engine has been rebuilt by VSE with a new clutch fitted so I just had to attach the gearbox and bellhousing. However the reuniting of the transmission unit would feel like a major milestone had been reached!

The bellhousing had already been ultrasonically cleaned and just needed the rear oil seal inserted before being bolted to the gearbox. Three lock tabs are used to prevent six of the bolts from working loose. The remaining two bolts, next to the clutch fork, use safety wire instead.

I’d never needed to use locking wire on previous vehicles so needed to purchase a pair of safety wire pliers. Eventually I managed to obtain an old pair on eBay and some 0.81mm stainless wire.

The pliers were definitely a good investment, less so was the wire that I purchased. It snapped as soon as a few twists were applied. I hadn’t purchased annealed wire – dooh! After purchasing the correct type, it was a lot more successful! The main point is to make sure the wire passing round the outside of the bolt head puts tension on the bolt in a clockwise direction.

The fitting of the clutch release bearing and operating fork is all very straight forward. The fork can be inserted with the bearing attached which makes fitting the securing spring clips much easier. The clips are held in place by the curved end sitting in a slight dimple in the fork arm.

The push-fit spring clips secure the clutch release bearing to the operating fork. The curved spring end sits in a dimple in the fork

The pivot pin was lightly greased and aligned with the grub screw hole in the fork before inserting

A little Loctite was used on the grub screw which locks the pivot pin in position. A lock nut is then fitted on the grub screw.

The engine was already sitting on the DIY trolley which will be used to roll it into position once the front frames are removed. Hoisting the gearbox to the same level meant it was simply a matter of rotating it to align the drive splines. Once the splines were engaged the gearbox could be rotated back again to align the bolt holes.

Supporting the gearbox with the engine hoist made the job much easier

It was also very helpful to have the engine mobile to align the two units

The weight of the gearbox was used to help push the gearbox onto the clutch splines

The two bellhousing support brackets needed to be installed before the full weight of the gearbox could be released. Finally the flywheel cover plate was bolted on to finish the job.

I did make the mistake of fitting the clutch slave cylinder when fitting the bellhousing to the gearbox but had to remove it to fit the lower bolt for the support bracket. I’ll make the final adjustments of the clutch just before the engine is installed.

One thing I’m not sure about at this stage is the orientation of the four vertical bolts for the support brackets. One of the bolts is longer than the others and so I guess must be used to secure a bracket of some description. Another question for the E-type forum ….

Fitment of the bellhousing support bracket is needed before it can take the full weight of the gearbox

A major milestone reached - a completed transmission unit ready to fit. I hope it starts!!

The rear of the gearbox has a sprung fitting to absorb vertical movement

The gearbox is supported at the rear by a large spring between a mounting bracket and the gearbox. The spring damps the movement of the gearbox but allows for a degree of vertical travel. The spring ends sit in rubber mouldings. The mounting bracket also contains a rubber bump stop to limit the gearbox travel.

Aug 312012
 

The two tried and tested methods for the engine removal are either lifting it out from above or lowering it onto a trolley and then lifting the body sufficiently until the engine is clear of the sub frames. Although I’ve heard of people, doing full restorations, who have lowered the engine onto a trolley and then removed the surrounding engine sub frames.

The difficulty with the removal from above is that the engine and gearbox come out together as a single unit and this requires it to be tilted at the same time as it is being lifted clear. I didn’t have a controllable method of tilting and wasn’t too keen on having such a weighty item dangling at such a height.

All the ancillaries had been removed and the lifting frame ready to drop the engine. The off-side front suspension still refused to come off!I was also doubtful that my home-made lifting frame, scaffolding cut to make a cross beam supported by A-frames, could raise the engine/gearbox unit to a sufficient height to clear the sub frames. So my only real option was to drop the engine.

The bottom out approach is documented in the Haynes manual and required the removal of all the engine ancillaries, the exhaust and inlet manifolds, alternator, oil filter etc. Once these had been removed I was then ready to lower the engine. Gulp! So far, so good.

At this point I must have taken leave of my senses when making some key decisions and the removal process descended into more of a farce!

I had some 1″ square Dexion speedframe lying around which included a set of castor wheels so I set about making a makeshift trolley. I’d lower the engine and gearbox on to the trolley, lift the car and then pull clear.

The first issues were the length of the 3-pronged corner connectors and that a length of 1″ square would be required between the connector and the castors. This resulted in a considerably higher platform that I’d originally envisaged.

The knock on effect was that, not only would I have to raise the front of the car even further, I would have to raise the rear of the car to reduce the body angle when the front was raised. This would allow the engine & gearbox to be dropped without hitting the sub frames. At this stage I should have reconsidered my approach to how I was dropping the engine.

The car was already supported on axle stands so once the ancillaries had been removed, the hoist could be used to lower the engine onto the waiting trolley. The castors were already showing signs of giving way, as can be seen in the photo above! I really should have reconsidered whether it was wise to continue. However, again, I ploughed on. Dooh!

The ridiculous height of the makeshift trolley caused no end of trouble! Not only that but it shows the first signs of the castors giving way under the weightThe front and rear were then raised alternately, supported by axle stands on building blocks. The rear was just about within the range of my trolley jacks but the front needed to be lifted via the lifting frame.

Once the front sub-frame was clear of the engine, the lifting frame was used to take the full weight of the front of the bodyshell. The supporting blocks were then removed to provide an exit route for my wobbly trolley. The trolley castors didn’t approve of being moved and their jaunty angle worsened severely as the trolley was delicately pulled clear!

At this stage I would have been in all sorts of problems had the trolley collapsed “mid-extraction” as the only lifting gear I had was in used supporting the bodyshell!

I did have to realign the trolley legs several times, taking the weight by an extended crowbar. It was very close but fortunately the trolley lasted just long enough to pull the engine clear. It was then mounted on a proper engine stand.

On a positive note, the lesson learnt for the rebuild is to use a more substantial trolley which is as low to the ground as possible and to have a backout plan in case something does go wrong. Even with the self-induced problems, I still think dropping the engine is the way to go!