Part 2 Cleaning an Inspection:

In the meantime, I’ve started to use my new parts washer, which now has 10 gallons of paraffin in it, to get the worst of the carbon off the engine parts.
So first parts to go in are the pistons, below you can see the results of before and after. All I can advise here is, take your time, let the cleaner do the work, and don’t be tempted to use abrasives; they’ll just scratch the aluminum.
For the more stubborn deposits I used a little bit of thinners, left on the head of the piston for 10 minutes or so, and a stiff nylon brush. I think it brought them up a treat.

Before, just as it came out of the engine and with 40,000 miles worth of carbon deposits.	Piston Before
And after. As good as new, I’ve no idea what the number references are, but the arrow faces forwards when the piston is in the block. This is number 2 piston, and I’ll be measuring the pistons for clearance and new rings after I’ve finished cleaning them all. Oh well.	Piston After

The Crankshaft

There are 5 Main Bearings and 4 Big Ends. But each big end has 2 con rods and pistons attached to it.

A good view of a main and big end bearings, showing the oil ways. Out of interest I don’t think the TVR crank is of particular high quality compared to others I’ve worked on. There is a lot of casting flash on the counter weights, which are the rough areas.

I found this a bit surprising. The RV8 uses 2 main bearing journal sizes. Large journal 2.5” and small journal 2.3”. With the crank having such a long stroke I expected TVR to use the larger journal size for extra strength. I don’t know if all 500’s are like this but mine’s a 1994 and it has the smaller journals

And here is a Con Rod with Piston attached. This end of the rod is known as the Little End, and the other end is the Big End. It really does make sense when you think about it.

ConRod/Piston

There are various ways of attaching the piston to the Con rod, and the part is called a Gudgeon pin or Wrist pin. This pin can run in a small bearing and can be held in place by little circlips at each end if the pin. Or more commonly and as found in the Rover V8, the pin is pressed into place and requires specialist equipment to remove without causing damage. Hence the reason my pistons are still attached to the Con Rods. 

A close up of a Big End, Ooh err missus, with the shell bearings and Big End Cap still in place.	The Big End
And here with the Big End cap removed. Notice the dowel pins used for location.	Minus End cap
Now a picture of the Con Rod itself. You can see a TVR id but I’ve no idea what the numbers represent.	The Con Rod with i.d.
Finally all 8 pistons and con rods, cleaned and ready for plenty of more miles.	Con Rods & Pistons
Piston rings. There are 5 rings but only 3 grooves in each piston. The wavy ring and the 2 thin ones to the left are oil control rings and all fit together in the bottom groove. The other 2 rings on the right are compression rings and fit into the 1st and 2nd grooves.	Piston Rings
This is how the oil control rings go together when they are fitted into the piston groove.	Oil Control Rings
To remove the rings from the pistons, just pries the ends apart and slide them out of the groove. Be careful they are very sharp and brittle. I’m not bothered about breaking any, as I’m going to re-new them anyway.	Removing Rings
Piston No 1 showing the gudgeon pin and the 3 piston ring grooves. These grooves have to be spotlessly clean before fitting the new rings.	Piston No 1

That’s the crank and pistons covered, now a look at the block, and main bearing caps, with particular attention being paid to the differences between a Cross bolted block and a standard TVR block.

Standard Block	This is a standard block with all but No1 Main bearing caps in place. The area arrowed is called the Register and is a machined area that the main cap mates with.
Mains Caps in Situ	A standard block showing the mains caps fitted into their registers. Notice the gap down either side of the caps.
Cross Bolted Block	The cross-bolted block has a much larger register area for the mains caps to fit against.
No Gap Mains Caps	Now you can see how cross-bolted mains caps fits into the register. No gaps.
The Cross Bolts in Situ	And in addition, to the larger register area, here’s where the cross bolts fit to give extra support and rigidity.
Cross Bolt Bosses	On the standard block the cross bolt bosses are there, but have not been machined. In my opinion it wouldn’t be a big job to convert a standard block to cross bolt, but you would have to get some mains caps to suit, and the block would need line boring.
Different Mains Caps	The 2 different types of mains caps. The top one is the cross bolted type.
Note Cross Bolt Hole	Here you can see the threaded hole for the cross bolt.
Extra Metal	And here you can see the extra material at the side of the cap.
No 3 Mains Cap	This is number 3 main cap, it contains the Thrust bearing. This is needed, as when you press the clutch pedal, you are effectively trying to push the crankshaft forwards, this copper area gives the crank something to ride against whilst your foot is on the clutch pedal. Simple when you think about it. There is a fair amount of damage evident at the edge of this bearing. It’s probably not detrimental, as it’s not part of the running area, but I’d like to know how it occurs.
Healthy Bearing	In contrast a fairly healthy looking bearing in the cross-bolted block. All of these bearings are going to be replaced as a matter of course.
Shell Bearings	A close up of some big end shell bearings. All of the shell bearings will be replaced.
Core Plugs	Core plugs, that’s what those 3 round objects are called. The RV8 engine has 9 of these, 3 on each side and 3 in the back. Again I’ll be replacing these with new ones.

 That’s it for now, back to the cleaning. In the meantime have a look at the bores now they’ve been re honed.

The bores show the crosshatch pattern that’s needed to help the new rings bed in and keep oil consumption under control.

Re Honed Bores

 Well even I’ve had enough of cleaning parts for now. So I thought I’d spend a bit of time on preparing the block before it goes into the washer tank. Now that the Cross-bolted block’s been re honed and I’m satisfied that its sound, I’ve decided that I’m definitely going to use it.

There’s absolutely nothing wrong with the TVR block, but as I have the other one and it’s been sitting in my garage for some time I may as well put it into service. Besides, if the rebuild goes pear shaped, I know I’ve got a sound block to fall back on.
That said, let’s have a look at the block and do a bit of proper work on it.

On comparing the 2 blocks side by side, I noticed this casting lump on the new block. It appears on No 1 and No 8 cylinders. It sits proud by about 5mm at the bottom, by the liner.	Casting Lump
The casting lumps have been ground away on the TVR block. I suspected the reason was because of the long stroke, that the con rod would come into contact with the casting as the crank spins. I set the crank into the new block and fitted No 1 piston and gently turned the crank by hand. Sure enough it was going to hit, so it was out with the Dremel, and a few cutting and sanding discs later, the lumps were no more.	Ground away Here
Next I decided that I’d clean out all the threads, so I can be sure of nice even torque settings when I come to put it all back together again. Use plenty of lube, and clean the tap between holes, so that you don’t transfer the dirt and swarf from one hole into the next. The mains bolts are ½” UNC. But always check, never assume anything. You can see the 2 blocks here, side by side to make comparisons, much easier.	Thread Cleaning
Now cleaning the side threads for the cross bolts in the mains caps, guess what? They’re M10. You have to be very careful with the Rover V8 when it comes to threads; it’s the only engine I’ve worked on that uses a mixture of metric and imperial threads.	Cross Bolt Threads
The front of the engine and the sump bolts are all 5/16” UNC.	Engine Front
Oil pickup is ¼ “ UNC.	The Oil Pick Up
Don't forget the holes on the outside. These are for the engine mounts, and are 7/16” UNC. So you can see, there are a fair old variety of different sizes, and we haven’t even got to the top end yet.	Engine Mount holes

 So what next? I thought I’d remove the core plugs and cam bearings, this should leave the block just about ready to go into the parts washer for the first time for a bit of a clean up.

Core Plug Removal	To remove the core plugs use a punch or flat chisel, and give them a good sharp smack with a hammer. Hit them on the bottom edge (the chisel’s at the top because the engine’s upside down) this will turn the plug.
Gently Does it	Then use a suitable pair of grips or pliers to retrieve the plug from the hole. Don’t worry if they fall inside, a bit of fishing about will get them out.
Cam Bearing	The cam bearings are a little trickier as access is pretty restricted. There is definitely the potential to cause damage here, so if you’re not confident, it’s probably best to leave it to a specialist. If you do fancy having a go though, use a punch and carefully drift them out.
C Head Bolt Holes	The block is now the right way up again so I can re-tap the cylinder head boltholes 7/16” UNC.
Core Plugs	Then I cleaned up the core plugholes with a bit of wire wool.
Parts Washer :-)	At last, into the parts washer, not a bad fit either. I knew the wife was wrong when she said the tank was too big. A man cannot have too many toys.
Air Cleaning	Once out of the washer, I cranked up the compressor and gave the engine a good blowing down. I paid particular attention to the oil ways and the boltholes.
Clean engine Block	And here we have it, one spotlessly clean and dry engine block. Very satisfying after all the hard work, and it’s so much nicer to be working on clean parts. I made a real effort to get rid of all traces of old gasket material and sealants. There’s no way I’m going to have any of this crap getting into my engine. The message from here on in is cleanliness, and more cleanliness.
Spotless Face	Again much effort has been spent on getting the block faces as clean as possible.
Effective Design	I know I know but I can’t help looking at it. It really is such a simple yet effective design.

That’s about it for the initial clean down and inspection. Now I’m going to have to start measuring clearances and check fit parts, before I can make a start on rebuilding the bottom end.
I know I’ve still got to do some work on the crank, but I can be doing that at the same time as getting the block ready to accept it.
Before I go any further though, the first thing I’m going to do though is make myself, a small engine stand, so I can work on the engine without having to keep turning it over.
It’s not too bad when it hasn’t got a crank in it. But as soon as you fit it, it not only makes it a lot heavier, it also means the block can’t sit flat on the bench.

	And here we have it a small adjustable stand that I made out of some scrap.
Nothing fancy but I can alter the angle very quickly, and clamp or bolt the base to the bench when I need to torque some of the tighter bolts.

Christmas Time

Just like Christmas my first delivery of parts. I’ll do a breakdown of costs at the end of the project.
This area of the project may come across as a bit disorganized; the problem is that certain parts arrive at different times. So I’m restricted to doing what I can.
It still comes under block preparation, but it my not be in a logical order. No matter though as all these jobs need doing, and at least I can get some of the more mundane tasks out of the way.
Once I’m ready I can give the block a final wash down and dry, and then start to rebuild the bottom end.

So, as I’ve got my new piston rings I may as well set about gapping them. All 32 of them.
The rings come in sets. Top, second and oil, don’t get them mixed up, and size each bore separately, then make sure they are kept with the relevant piston until fitting time.

As they arrive from the supplier. Good instructions and well marked so no need to get them mixed up.	New Piston Rings
I’ll do the top and second rings first as the measurements are the same. Begin by putting the top ring the right way up into the cylinder bore.	Cylinder Bore
Then using an upside down piston, push the ring about an inch down the bore. I used a marker pen to mark the piston 1” from the top.	Helpfull Piston
Using a feeler gauge, check the gap. Mine were all around the 0.15mm to 0.25mm mark before gapping. The top and second rings need to be between 0.40mm and 0.65mm to be correct.	Measuring

 When using the feeler gauges, I prefer the following method. I open out the smallest size required, in this case, 0.40mm, and the largest size, 0.65mm, and the size I’m aiming for 0.45mm. I file the ring until the 0.40mm gauge fits in, then just a few more strokes with the file will take it out to a ‘tight’ 0.45mm or a ‘loose’ 0.40mm. Then to make doubly certain, I make sure that the 0.65mm won’t go in at all. This way you know you’ve got to be between the tolerance figures, and preferably towards the lower tolerance.

Use a small file to remove material from the gap. File a bit from each side and try to keep the edges square. Only do a bit at a time and keep reinserting the ring into the bore for re-measurement.

Small Filing

Be careful when handling and filing the rings, as they are very brittle and easy to snap. As with all these jobs take your time, and don’t be tempted to take short cuts. As a guide it took me the best part of 4 hours solid work to gap all the rings. But I know they’re right.

The oil rings are a little different, the control ring will be checked when it is fitted to the piston, and I’ll show that when I do it.

But the 2 rings that sandwich the control ring are very flimsy, so extra care is required. The gapping method is exactly the same as for the top and second rings, the only differences being the tolerance, 0.38mm to 1.40mm and the fact that they do not have a right or wrong way up. That’s quite a large tolerance, but again I aimed at the lower end and set them to the same as the top and second rings, i.e. 0.45mm.

I’ll show piston ring fitting when I’m ready to install them into the engine, but I’ve still got plenty to do until I reach that stage.

One of the jobs I’m not looking forward to and would like to get behind me is fitting the cam bearings, and that’s what we’ll be looking at next.

I knew the cam bearings were going to be tricky, but with a bit of for thought and effort, they should go in undamaged. I started by turning a few spacers at work. The spacers are made from a machineable nylon type material, and I turned 6 in all. The reason I needed 6 is that the five cam bearings are all a different size to each other. They’re stepped down in size from the front of the engine to the rear. The front one being the largest and the rear the smallest.

I machined 5 of the spacers so that they were a tight fit into the bearing bore with no bearing fitted, and the sixth one was bigger than the largest bore hole.
The idea was that I would use them as drifts. I also decided that I would put the bearings in the icebox of the freezer for a couple of hours prior to using them.

Placing the bearings into a tub full of ice and an ice block, and then into the freezer. I took them out 1 at a time, as they were required.

Iced Bearings

I decided to do the least accessible first and work my way forwards and backwards from there. So as number 3 is right in the middle of the engine this is where I started. I then did number 4 and number 2, leaving the two easiest, 1 and 5 until last.

Remember to sort out the bearings before starting, measure the outside diameter and mark the largest as number 1 (front of engine) down to number 5 (rear of engine).

I’m going to show number 1 bearing at the front of the engine, as it’s easier for illustration purposes, but the principles are just the same for the rest, it’s just that they’re trickier to get at, hence the plaster in the first photo.

Start by lining up the hole in the bearing, with the oil supply hole in the block.	Beraing Hole line up
Then using the plastic bush I tapped the bearing down evenly with a hammer.	Helpful Plastic Bush
I kept going until the bearing was flush with the block.	A Gentle tap
Then I used the plastic bush to draw the bearing the rest of the way into the block.	Nearly There

 That’s basically it, for the cam bearings, again the only advice I can give is take it steady, don’t force anything, the bearings are tight, but they should only need moderate force to set them in place. If you have to swing on the end of a ratchet to get them to pull in, there’s something wrong.  In all honesty, this is one job that I could quite easily have left to the specialist, but as the bearings are only around £20.00 a set, I thought it was worth a try, and now having done it I’m glad I did.
Now it’s time to come clean, although up to now the project has gone reasonably well, I had my first taste of problems today. Basically I caught the edge of number 4 bearing as I was pressing it in, it’s easy done believe me, anyway I tried to fettle it and remove the burr with a file, but just ended up making matters worse. So the bottom line is I had to buy a second set and do this one again.

Having fitted he cam bearings, a job I wasn’t looking forward to, I feel that I can now start to make a bit of progress with the rest of the block preparation.
The next thing I did was carefully just trial fit the cam to double check that the bearings were all in the right place and there was no binding.

Once this checked out ok, I decided to give the block one more wash down in the paraffin bath, just to make sure that any swarf or filings I’d created from sizing the piston rings and fitting the cam bearings, was got rid of.

So it was back into the parts washer for a good scrub down, and then a thorough drying with the air nozzle.

Oh by the way, I know I shouldn’t have to remind people of this, but when you’re using an air line, please please wear safety glasses, you’d be amazed at what flies off the engine when using high pressure air tools.

In fact whilst we’re talking about personal safety, I always wear safety boots when I’m working in the garage. I know I wouldn’t be happy if I dropped the crank, but I’d be really annoyed if I broke a few bones in my foot as well.

Anyway safety talk over, next job was to fit the new core plugs.

I started by removing all traces of grease and oil from the seating face with a clean paper towel and some cellulose thinners.	Cleaning the hole
I also wiped the edge of the plug before applying a light bead of high temperature silicone sealant. Apply these sealants sparingly, the plugs are a tight fit, and excess sealant will just get squeezed out and make a mess everywhere.	Appling Sealant
Then just push the plug into the hole, and lightly tap around the edge until it’s flush with the block.	More Gentle Tapping
Then use a good fitting socket that sits on the edge of the plug, not the inside, to knock it just below the face of the block. I found that a 1 1/8” socket was a perfect fit.	Helpful Socket
Here you can see the final result, note that the plug is just below the face of the block. Wipe the area clean and job done.	Just Below Surface
That's it, 3 either side, 2 in at the rear and finally the cam plug in the middle at the rear. All cleaned off and ready for the next job.	Voila

So now that a few of the messier jobs are out of the way, I can start to fit a few parts that require absolute cleanliness. I need to fit the main shell bearings so that I can check the clearances later on.

I’ll start by fitting the block shells and then move onto the main bearing caps later. The reason for keeping these two tasks separate is again to avoid the opportunity for mixing parts up.
Main bearing shells as they arrive from the supplier.

Main Bearings	Main bearing shells as they arrive from the supplier.
Upper and Lower	Once out of the packaging I separated the 2 types of shells from each other and just kept the ones I needed on the bench. If you look closely you can see they are marked “upper” and “lower”. The upper ones are those with the hole and slot, and these are the ones that fit into the block.
Cleaning	Again start by cleaning the shell register with a paper towel and thinners. Also clean the back of the shell bearing.
Insert The Bearing	Insert the bearing by locating the little tab into the corresponding slot in the block.
Press home	Then press the bearing home by pushing down in the centre.
Straight Edge	To make sure the bearing is even on both sides, I used a small straight edge across the face.
Clean The Side	For number 3 bearing, the thrust bearing, also make sure you clean the side face, as well as the top face.
Thrust Bearing	Fit the thrust bearing in exactly the same way as the others, just need to press a bit harder to get it seated.
Finished	And there we have it, new cam bearings, big end shell bearings and core plugs all fitted. Just need to do the caps and check the clearances now.
Cleaning The Cap	As before, clean the face of the cap first. And don’t forget the back of the shell bearing as well.
Locating	Then just as with the block, locate the tab into the slot.
Pressing Home	And then using thumb pressure, press the centre of the bearing home. Turn the cap the other way up and press it down on a flat surface just to make sure it’s even on both sides.

 I made some attempts at checking the bearing clearances by using a set of internal dividers and a vernier gauge, but to be honest I couldn’t get the accuracy and consistency required to be confident in my measurements, so I had a think about it and spoke to a few people and then decide that the best way for me to check the bearing clearances, was to use Plastigauge.

Plastiguage is a thin strip of a plasticine type material that you lay onto the bearing surface, then tighten down the cap to the correct torque, which squashes the plasticine between the cap and the bearing.

You then check how much its been squashed against a gauge that is in the kit.

I’m sure it’s not as accurate as using expensive engineers bore gauges, but I don’t have one of these and when I checked out the costs, they were prohibitive.

It would be very difficult for me to justify spending well over a £100.00 pounds for an instrument that I would hardly ever use again.

So I had little choice really, and as I hadn’t used Plastigauge before I thought it would be interesting to give it a try. I bought the Plastiguage from RS Components for about £4.00 a pack.

One pack would easily be enough to do an engine.

So here goes.

Carefully fit the clean crankshaft into the engine, make sure the crank journals are dry, and that the shell bearings are also dry.

Plasticguage	First break a bit of the plastic off, roughly the width of the bearing and lay it across the bearing as shown. I laid a piece on each main bearing so I could do them all in one go.
Main Cap	Then fit each main bearing cap and torque the bolts down to 55 ft/lbs. the rear cap is torqued to 65 ft/lbs. It’s important that the crank doesn’t turn during this process.
Exit the Plasticine	Here you can see how the plasticine has squeezed out now that the caps been torqued down.
Using the Guage	Remove all the caps and use the gauge provided to check the clearance. Place the measure at the widest point. And whichever one matches the closest is the reading you want. Sometimes it can be just between 2 scales, if this is the case it’s quite acceptable to split the difference. So if it was between 1.5 and 2.0 thou. You would say it was 1.75 thou. (Thousandths of an inch).
And again	The plastigauge doesn’t always come off with the cap, sometimes it stays on the journal, this doesn’t matter, just use the gauge on the crank instead.Another bearing just for good measure. (Pun intended).
All the Caps	Now all the caps lined up. These all came out at between 1.2 and 1.5 thou. The tolerance is anything between 0.9  and 2.4 thou. So all in all a pretty good result.

Next job is the big end bearings. And exactly the same principle is applied, the only difference being that I removed the crank and placed it on the bench for this job.

Start by cleaning the surfaces of the con rod and the big end cap.	Cleaning the Caps
Clean and fit the new shells to the rod and cap, unlike the mains shells these don’t have a top and a bottom, so any shell out of the pack will do.	Clean and Fitting
As with the mains lay a piece of plastigauge across the shell.	More Plastiguage
Fit the relevant pistons to the correct journal and torque the cap bolts to 38 ft/lbs.	Torquing the Cap Bolts
Remove the caps, this time you can see how the plastigauge has stayed on the journal rather than the cap. And as before check against the gauge.	Checking With Guage
Again all my clearances worked out at between 1.5 and 1.7 thou. The tolerance is the same as for the mains i.e. between 0.9 and 2.4 thou. So all in all I’m now satisfied that my clearances are well within tolerance.
Here’s an interesting point. My big end shells were 20 thou over size, this means that at some point my crank has had the big end journals re ground. On making a few enquiries to people in the know, it appears that my crank has probably not been re ground at all but in all likelihood left the factory with undersize journal.

I can well believe this as, as I mentioned before the TVR crank casting is certainly not the best I’ve seen, and it’s quite probable that to get the required finish on the journals, the re grind company would have to take it down to the first service size.

I don’t think it’s anything to be to concerned about as the amount of wear in the bottom half of my engine is negligible, so with a bit of luck and good maintenance I should be able to do at least another 100 thousand miles before I need to look at the bottom half again.

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