A fight with a TR6 heater

So, as the car is being pretty much totally disassembled for the respray I thought it would be a good time to rebuild the heater. After all it is pretty much "buried" deep behind the dash and my heater motor had been droning for a while. So job one... remove the heater. this entails.
1)  removing a load of stuff that is under the dash
2)  disconnect the cable from the heater control on the dash
3)  disconnect the heater pipes (air and water). Beware of flooding the footwell with water!
4) unbolt the 4 bolts that attach the heater to the firewall..

Simple! or perhaps not.. all went well until stage 4 and then 2 of the bolts (that point upwards and attach to captived nuts "inside" the upper part of the fire wall sheared. Bu^&er! Deep breaths!! will sort that later.

withdrew the heater from under the dash and had a look at it.

As you can see it is not really what's called high tech. It is essentially a biscuit tine with pipes coming out of it. Two small ones for water and 4 large ones for air (you can only see 2 in this picture). The lower one is cold air (it is before the heater matrix) and the upper one on the right is hot air (after the heater matrix). There is also a motor (hidden under the dome on the left) and a flap on the right which (in theory controls where the air goes). I continued to take it apart (fairly easy if the self tapping screws that hold it all together are not rusted up!)

And heres's the motor (two speed) and fan. Now I knew the motor was a bit iffy and there was certainly some play in the bearings. So I looked at the price of a new one and had  to sit down "how much!!".. to calm down I did a bit of trawling of the internet and found some inventive people across the pond had found a cheaper equivalent motor. Where did they find it? from a school bus of course!
Link to alternative TR6 heater motor. It has the same shaft diameter as the Lucas one in the TR. is two speed but without the external resister found on the TR version.. and best of all it was less that £20. Only issue would have been shipping, but I was working in the US in the next few weeks. So here it is in comparison to the Lucas item.

You'll see the size is about right. Note there is no shaft on the lucas one (left) as I had to cut it off to get the fan off. The only thing that is missing is the mounting flange. However I managed to rig one up using in jubilee clip (that was large enough to go around the complete motor body) and then a set of small "L" shaped brackets. Works great.

then connect to a battery for a test and wow.. what a difference.. the motor is smooth and silent and the power... amazing!

Next I stripped all the old paint and rust from the "biscuit tin" and then reassembled including new bits of foam around the heater to ensure that the maximum amount of hot air goes through and not around the matrix. (I use closed cell foam which comes on a roll for going under laminate floors, its cheap and self adhesive).

The final piece in the heater jigsaw is the heater flap. In theory I think the idea is that in one position the flap (and its foam backing) shut off air going through the heater forcing all the air (cold) out of the dash vents. In a second position the flap uncovers the pipes on the hot air side allowing air to flow to the demist and under dash vents. I think there is a third position (or at least there was in mine) with the flap fully down and poking out of the "biscuit tin". In this position the hot air was directed out of the bottom of the heater to the feet. All great in theory but position one didn't work because the foam had disintergrated (so new foam) and position 2 wasn't great as their were large gaps around the edge of the flap. This meant that the demist (perhaps the most important function was awful!).

So what to do... With a bit of lateral thinking I came up with a solution... draft excluders.. cheap (99p) and a MUCH better seal. I just cut them to size and riveted them in place.

Now all I have to do is refit.... But hang on... not so fast.. remember I had sheared two of the bolts that hold the heater in. you can see one of the offending studs pretty much below (the rusty patch on the front edge of the circular hole.

This is not going to be easy to drill out... So how about an easier strategy... weld in some replacement studs

Will need to tidy the welds.. but problem solved.

Welding in the new rear deck.

So rear deck removed.. now time to put in some new metal. I decided to buy a complete patern rear deck and front passenger side deck extension (the piece that extends from the deck forwards to the B-post). These panels are not cheap and I am always a little wary of quality. In this case the quality was a little mixed. The rear deck was pretty good while the extension needed some fettling as it was a little too long. A trial fit looked reasonable after some fettling.

You can see along the right hand edge of the deck I have already drilled the panel for some plug welding. You can see the extension in place here. If you look closely I have also begin to weld the rear deck to the vertical support (below the mole grips)

 And on the otherside:

Then I needed to sort out the plug welds for the rear. You can see the holes in the deck panel and how they line up with the lower horizontal support (well most of them do!)

Which I then plug welded (note I placed some silicone welding sheet below to protect the fuel pump etc.)

I also welded the panel to the inner wings and then checked alignment with the wings bolted up.

Not bad.. There is a bit of a gap (about 2 mm) where the wing meets the inner wing along the side of the boot. Interestingly when I took the wing off there was a rubber gasket between the wing outer and inner wing. I havn't seen this in the parts catalogue..
And the whole thing complete with new bootlid.

Much better!

Removing the rear deck.

Given the likely issues with the rear deck I decided to strip the rear panel with a wire brush (on my angle grinder). Unfortunately the passenger side of the rear deck was quite a state. A number of holes (from rust) meaning that both the deck and the extension from the deck to the B-post on the passenger side needed replacing. So this meant removing the panel. So using the angle grinder I sliced down the side of the inner wing and then drilled out all the spot welds that attach the back of the panel. You can see these on the picture below (the shiny dots on the piece of steel going across the car)

 Leaving a big hole :-(

Now all I have to do is weld in a new deck and front extension.. not much then!

Another stage in the rolling restoration

Its winter again and time to continue the rolling restoration of my 1972 TR6 PI. Last winter I carried out a chassis change including an engine refresh and suspension rebuild. This year I decided it was time to address the bodywork. From 20 feet the car looks OK, however once you get up close it becomes clear that the paintwork isn't up to much. In fact it has more "orange peel" than a tangerine!

Luckily there doesn't seem to be too much evidence of rust. The underside is clean with new floors and sills. Otherwise there is one rust bubble on the back of one of the front wings and another on the rear deck (the bit between the cockpit and the boot lid).. O yes and a small hole in the rear edge of the boot lid. Overall, the one that worried me the most was the bubble on the rear deck.

The first thing to do was to remove the 4 wings. These are all bolt-on and should (in theory) be relatively easy to remove. First to come off were the front wings.

These were pretty easy to remove with screws along the top edge and the bottom of the sill. The two sets that were more of a challege were those that go into the front edge of the B-post and those below the head-light. Both of these are accessable from inside the wing. (I should add that you need to disconnect all the electrical connections and off course the bumpers. An examination of the inner wings showed very little rust. just a little on the top flange of the passenger side front wing.
Then I had to remove the rear wings. Again this was just a case of unbolting. There are screws along the top edge (accessable from inside the car), the sill and then underneat the rear light (accessable from inside the wing). Once these wings were removed there was a rather nasty sight at the top of the passenger side wing.

There also seemd to be quite a lot of filler covering the rear deck..

Happy Ending

Hi all,
Well not blogged for some time... Mainly because life has been busy, but that is not to say that nothing has been going on with the TR6 project. In fact loads have happened. By the end of February I had competed rebuilding the chassis (see below).

And then it was a simple matter of rolling it under the body

And then just lowering the body. This time I used my engine crane to lower the body. I attaced it via the seatbelt mounts at the rear and the body to chassis mounts at the front.

And after some slight adjustment the car was back together

Everything pretty much lined up OK with just some very minor adjustments to two of the chassis mounts. I have to say it was nice to see everything back where it should be.

The rest of the reassembly, as they say in the Haynes manual, is just the reverse of dissassembly. However I did treat myself to some new wheels :-)

So over all the process, which was started in August 2014 was completed in March 2015, working only weekends and the odd evening.. Not bad really.
And the question then is.... Am I happy? Well I drove the car to the Spa Classic in Belgium, A 1000 mile weekend with a few laps of the GP circuit thrown in for fun.

Amazingly after the laps every vital sign of the car was resolutely in the middle of the range.

 The car behaved reasonably well with only 3 issues.
1) The rear telescopic shock mounts came loose and needed to be tightened a couple of times (now sorted with the use of a couple of nylocks.
2) One of the injectors failed (see below)

3) The car would idle no lower than 1300 rpm (hopefully to be sorted this winter with a new set of recon throttle bodies.

Dynamically the car seems good and the new cam makes the engine much smoother. Power seems pretty good and we returned over 30 mpg on the run. So over all worth it!

Finding top dead centre and timing the camshaft

As can be seen from my earlier posts most of the valve train is very worn.. Not surprising given the miles on the car and it's age. So as I have already mentioned I needed to replace pretty much everything apart from the sprockets (which are in good nick) and the cylinder head.

One thing that you have to consider when fitting a new camshaft is ensuring that it is timed with the crank. For example this means ensuring that when the piston is moving up the cylinder bore on the compression stroke both valves are closed allowing the mixture to be compressed. To ensure that valves and pistons move in perfect harmony the motion of the crank synchronised to the motion of the camshaft via the timing chain. Unfortunately not all camshafts are created equal and it is essential that a new camshaft is timed to the crankshaft when it is fitted.

The first stage of this process is to find top dead centre (TDC) on the crankshaft. This is the position when the piston in cylinder one (nearest the front of the engine) is at the top of it's stroke. This position is generally marked on the crank pulley, but when the engine is in bits it is good to check the marks havn't moved. There are many ways to do this but my favourite uses a device called a piston stop (see above). The piston stop is made up of a piece of steel that is bolted (in this case using the head studs) across the top of the number one cylinder. Protruding from the centre of the piece of steel is bolt. Now when the engine is rotated that the piston stops when it hits the bolt.

To determine TDC a timing disc is first attached firmly to the crank and a pointer e.g. a piece of steel wire is  attached to a bolt on the front of the engine.(see below). The crank is then turned clockwise until it touches the stop. the number on the timing disc that the pointer is next to is written down. The same process is repeated in the anti-clockwise direction. We then know that TDC is halfway between the two numbers.

 In the case below I had already lined up the crank to the TDC mark made when the engine left the factory. The two figures I read off were 26 degrees before and 26 degrees after TDC indicating that in this case the TDC index on the pulley is in the correct place. This is NOT always the case and I have seen figures that are anywhere up to 20 degrees off. In these cases setting cam and ignition timing using the incorrect marks could have caused big issues (bent valves any one!)

Fitting Valve Springs

So next need to fit the valve springs. Now in the past when I have done this I have found it quite fiddly.. The collets that secure the spring to the top of the valve are small and always flick out into oblivion if the spring isn't aligned when you release the pressure...
So this time I made sure I had plenty of collets. In fact I had twice the number required as I had stripped 2 heads, the 9.5:1 and 7:1 compression.

 -o-

LATEST NEWS: O yes, should have said, idea of fitting a supercharger is on ice until next winter. Moss have temporarily discontinued the supercharger kit while they carry out a redesign. So will be going back to plan A. Refitting the 9.5:1 and going back to Lucas Petrol Injection.

 -o-

 So back to the head.. The procedure for fitting the springs is relatively simple and requires one specialised tool, a valve spring compressor, which you also have to use to take the springs off. Stage 1. Fit the inner valve seat and the rubber o-ring valve stem oil seal. 2 & 3. fit the spring, spring cap and the valve spring compressor and compress the spring. It is worth noting here that there are 2 types of cap on the TR engine. One is in two pieces and the other one piece. The one piece cap fits on the inlet valves while the two piece is for the exhausts.

The two pictures show how the compressor is seated on the head (actually the close up shows the compressor slightly off centre, but I changed this before fitting the collets). 4. insert the two collets into the groove at the top of the valve. If you can't get them in tighten the compressor a bit. I find a bit of grease on the collets helps them to stick. now release the compressor. The release the compressor, and if all is right the collets should drop into place like those shown in 4.