Triumph SC engines

[Martin Evans]

Has anyone ever experienced a 1500 Triumph engine, that devours just the two cam lobes (In under 10000 miles), from the front cylinder of the engine? It has happened twice and I can’t see that it is the cams (Kent TH5); it has to be oil feed related.

The Triumph engine is something of a comparative rarity, in the MG world and some seem to dismiss it as not being an MG engine (Despite the fact that MG engines were Wolseley, Morris, Austin or Rover based; even the MGA twin cam unit was based on B series block). As a result, most of the engine specialists are geared towards A & B Series engines (Not counting XPEG/XPAG and earlier) and I wondered who are the Truimph engine experts

[Toledo Man]

It sounds like a blocked oilway. I think you're going to have to bite the bullet and get the block dipped to clean out all the crud. I suspect that the regular oil changes have been neglected and sludge has blocked some of the oilways. The 1500 engine has a bad reputation for the weak bottom end but if good quality 20w/50 is used and changed regularly it shouldn't give you any major problems. There are some knowledgeable people on the TDC forum who are better able to answer your question than I could.

[Martin Evans]

Oil changes have been annual (Less than 1500 miles) and each time a new cam was fitted, the engine was rebuilt (By Oselli and then Aldon, who I would hope cleaned out the system). Oil has been Valvoline Synta (I seem to recall that's what it was called) 5W/50 and for most of the "Second" period, Penrite HPR 30. With both cams, only the front two lobes failed. I don't feel inclined to rebuild the engine (It didn't solve the problem last time) but I need to get to the bottom of why this has happened, before I fit a new cam and followers.

In the Midget, the 1500's reputation was even worse, since the cooling, of both oil and water, wasn't good. To this end, I fitted an oil cooler (With thermostat), improved the airflow to the water radiator and even put vents in back of the bonnet. Overheating hasn't been a problem and the overdrive box has cut the revs a lot of the time.

As you say, it could be a blockage (But why and why there ) or it's a weakness in cam lubrication with these engines; but why just those two