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1973 Triumph Spitfire Engine Rebuild 

Prior to be starting to build this web page, something unfortunate happened. I used my phone to take all the pictures for the engine and rolling chassis rebuild stages. Soon after, my phone totally gave up on me and I had not downloaded the pictures. Fortunately I was able to retrieve the pictures saved on my SD card but for the pictures that were saved in my phone's internal memory..I guess they are gone forever. But anyways, at least I have something to show and what is important is for me to share what I learnt.

September 2016

So after parting it out, I sent the cylinder head and block to Weston Cylinder Heads located at Sheppard and Weston in Toronto. For the cylinder head, I had the exhasut valves and valve seats replaced along with have liners installed in the valve guides. The head was also decked. The mains on the crankshaft was quite warped and I had them ground down by 01. As for the block, I had the bores oversized by 02. I didn't deck the block since the bores are recessed. I have seen others deck it but I didn't feel comfortable doing it since the design of the head did not allow the slightest intrusion of the pistons into the head's valve cavity. One of my friends was blasted the oil pan, valve and timing covers for me. I had them coated with orange VHT paint. This is one of my regrets as I was not impressed by the paints quality. It has zero tolerance to degreasers. I used black Plastikote on the block and it was of much better quality. I painted the head with silver VHT.

Overall, I was happy with the paint scheme and like the orange-silver-black contrast.

I replaced all the seals, bearings and gaskets.

Machined mains. The rods looked polished so I kept them stock.

It is imperative to keep all the parts super clean and lube during re-assembly. The slightest amount of dirt on the journals can cause premature wear.

Doubele checked the end-float on the crank. I put in new shims but didnt have to over size to meet specs in the tech manual.

So the aluminum block that interfaces with the front crank seal had the center fore-aft tapped hole stripped (The lump). I re-tapped the hole 3/8 fine. The center up-down holes for the oil pan was also stipped which I re-tapped as well.

I glued all the new gaskets with 3M Aircraft Gasket Sealant.

For the stripped studs on the exhaust manifold, I heated the material around the stud with oxy-acetylene until it was glaring orange. This softened the material around the stud. I made sure I wasn't heating the stud too much because that would just cause it to rip off when I turn it with the pliers.

There was a hairline crack on the center tube of the manifold which I mig welded. The cast iron was quite pourous so the welds would easily cold crack. So I cracked up the amps and put on 3 passes.

I used new trimetal bearings for the mains and rods.

I used a dial indicator as part of an effort to attain perfect top-dead center. This step isn't necessary in my opinion since I figured (by doing this) that the mark on the crank pulley is quite accurate.

New cam followers.

New head gasket - be sure to have the right gasket on you. There gaskets are unique for recessed and non-recessed heads.

After bolting on the head and installing the cam came the rocker assembly. Previously I had cylinder 1 set to top dead center. Now its time to time the camshaft and this is when the dial indicator comes handy. In order for perfect timing to be achieved, the exhaust and intake valves have to be at the balance point (The rocker for the intake starts to push down as the rocker for the exhaust stops moving up). Note - I did not have the timing chain installed at this stage. The timing cover is on because it has the 0 degrees mark that lines up with the mark on the crank pulley.

I then assembled the chain. The cam sprocket moved very minimally but that was beyond my control. The chain did not sit on the cam sprocket with complete ease when the sprocket was at its "perfect position". I am thinking this is due to me using a new chain and it is a bit shrunk down by design to allow for stretch during operation.

Setting valve lash with the shim.

It oil pan gasket would not stay put so I used paper tape to hold it in place. Once the whole thing sat on the head, I pulled the tape out. Later on after the build when I started to fill the engine with oil, I noticecd oil was seeping out. I then took of the gasket and sealed the valve cover with Permatex high temp Silicone.

Last but not least, the oil pan. The brown gooey stuff you see there is the 3M Aircraft Gasket Sealant.

So before dropping the engine, I attempted  to install the distributor and I am glad I had that done sooner than later. So the distributor drive gear is driven by the camshaft. This gear not only drives the distributor but also the oil pump shaft. The top side of the gear has to be timed and has a key slot onto which the distributor drive shaft needs to sit into. If it is not timed accurately, you will  not be able to utilize the distributor's anglular tolerance range to adjust the timing for the distrubutor's contact points. The drive gear also has a slot on the underside that is meant to interface with the tab on the distibutor shaft. This is interface is not for timing purposes and is meant to keep the shaft and gear engaged. Because I installed the oil pump first, I was having to drop the drive gear in a manner that would allow it to be timed properly and simultaneously interface with the tab on the oil pump drive shaft. This proved to be a challenge since the gear was splined and it would turn as its being dropped in place. Because it would turn there was no way for me to get it to sit on the oil pump drive shaft tab without having the tab oriented at the perfect smallest fraction of a degree. Not only that, as the gear would turn as its being dropped, its final position would have to be the timed position. So I ended up having to take a step back. I decided to take the oil pan off and subsequently the oil pan. I then dropped in the drive gear and assembled the distributor. After that, I dropped in the oil pump, turned the shaft until the drive shaft tab slipped onto the slot on the drive gear. and then bolted on the oil pump housing.