Sunday, 6 April 2014

Head Work

Although this is one post, this represents 3 evenings and 1 weekends work, I was too tired last night to do an update!

I took the Sprint head to my local engineering shop in the week, and got it back after a light skim , it did have a slight warp.

Most of the past 3 evenings have been spent cleaning the valve gear and other items, which were covered in filthy baked on oil deposits, and modern degreasers don't work like the old ones, so by Saturday lunchtime I had a re-assembled head. There was very ltittle wear in the rocker shaft and rockers which was nice, but one or two items were missing when I stripped the head down, 2 dowls which help locate the cam bridges, and there was an incorrect long stud, head to block. These came off the second hand engine I have recently purchased off ebay, so I ended up with this

You can see why the pistons need cut outs for the inlet valves

I then refaced the oil pump cover to remove the score marks in its surface and refitted this and the oil filter

So time to check the valve clearances. I had assumed that as the head had recently had a new camshaft and the shims done, that they would not need attention. Strangely ALL the gaps are too big by 3 or 4 thou, and I had ground the valves in, so I had expected them to be a little on the tight side. But no, so I need a bucket full of shims to complete this job.

The second hand engine had also provided a brass expansion bottle, - my current one is plastic and these split, and a proper sprint air box. These rusty old items were dropped off at my local blasters, and I also painted these this weekend, after hammering out the dents  in the airbox

While these were drying, I decided to service the Stag in case I don't complete the Sprint for the HCR. - We drove about 8000 miles in it last year so it was overdue an oil and filter change, and I needed to check it over for its MOT which is due on the 2nd May. Needless to say another rubber boot had failed, this time on a lower ball joint, so I have ordered a set of those to be fitted later, and I noticed some of the water hoses have some small cracks so I have ordered a new set of water hoses, before these let me down too - I don't want 2 more head jobs! Came to start it, and the starter was playing up, so I removed that and cleaned the corroded solenoid contacts, still its ready for the HCR, even if I am not.

Back to the Sprint engine then, because of the water pump failure I am fitting an external electric pump, so the first job was to blank off the hole where the original pump fits with a brass bung - this is like the original cage on the Sprint / Stag pumps but solid - the bolt is there to stop the bung lifting out and needs adjustment so its a few thou below the water pump cover. Two O rings on the bung keep the water and oil apart.

That done, I fitted the cover and plumbed in the electric pump

I am going to change this slightly, by replacing the pumps inlet elbow with a straight input so that it can have a direct straight pipe to the radiator, rather than the 2 right angled pipes it has now, this will also let me drop the pump a few more inches so its slightly lower.

I then fitted the head, with all the pistons halfway down the bores, so I can do the pallet shims in situ. The head is not torqued down yet as the angled studs go through the cam bridges.I will also need to connect the cam to the chain too .But I did then get the exhaust flange bolted up, and the carbs fitted. The distributor is still out as I intend to spin the oil pump drive with a drill to get oil pressure up before I fit the distributor. The water pump wiring needs completing too as I have also bought the controller, which as well as controlling the water pump will switch the electric radiator fan off and on too

And that was it for now

No comments:

Post a Comment

Where am I?