In the spring of 1997 the engine developed some kind of fault. It became difficult to start, and produced copious quantities of white smoke until it warmed up, which took up to ten minutes on a cold day. Having had the injectors and pump serviced fairly recently, I decided the head gasket needed changing.

Having taken it apart, I found there was more to it. The head bolts were tightened down so much that a bar about 1.5m long was needed to move them. The gasket showed signs of blowing between bores and into the head bolt channels. The No 1 piston had suffered some damage around the top, leaving some aluminium stuck to the cylinder liner.

The engine with cylinder head removed. [Click on the image for full-size picture.]

I took the head to my local Perkins dealer for overhaul. Having taken it apart their verdict was that a replacement would be a cheaper option - it needed new valves and guides, and the waterways had corroded to such a depth that skimming would not recover it.

In view of this I then removed all the pistons, finding that all the rings were worn, two big end shells were scored, and the No 1 piston was badly damaged around the top. The cylinder liners had suffered varying degrees of scoring, especially No 1. The dealer's view was that all the pistons needed replacement, and probably also the liners.

At this point I considered a number of options:

1. Have the head repaired, with new pistons etc
2. Get a reconditioned head and new pistons etc
3. Get a factory-reconditioned 4.203 engine
4. Buy a factory-reconditioned 4.236 engine
5. Buy a new Perkins engine

A recond head was a much better proposition than their estimate of the repairs required on the existing head, and would cost about £1700 in all. An exchange engine turned out to be unavailable (the factory doesn't have any 4.203 blocks). A recond 4.236 would cost about £4000 (no exchange allowed with the 4.203 engine), but would require considerable work to fit, including a new adapter kit at about £500. A new engine would be about £7000.

Before comitting to anything I took the head to a local engineering company with experience of Perkins engines. Their verdict was that it did not require more than a light skim, and that this with new valves and guides would cost no more than about £400. So I went with this option, also getting a complete set of pistons, liners, and big-end shells.

The first major difficulty was removing the old liners. I borrowed a tool to fit under the liner and draw it out using a long bolt. I tried No 1 first - it didn't move until I had chiselled away a quarter of the liner, and even then required a bar 2m long. No 2 came quite easily, no 3 rather harder, and no 4 required about a third of its depth chiselled out before it came.

The engine block with cylinder liners removed. Some old damage can be seen around the rim where the liner lip sits.

The old cylinder liner removed intact from No 2 bore, and the liner partly broken out of No 4 bore.

I ordered the new parts before taking the old cylinder liners out, and the dealer supplied new liners made of chromed steel. The old liners turned out to be of the other type fitted to these engines, namely cast iron. This left a problem in that the lip at the top of the chromed liners is much smaller than that on the cast iron liners. The engineering compant who repaired the head made up a set of spacer rings to brint the lip thickness up the that of the old liners.

A new chromed steel liner with its spacer ring installed, and the other spacer rings.

The job is currently at the stage of the first new liner being almost installed. More news as it progresses...

Back to Land-Rover index page