More Breakdown Bother

You may have enjoyed reading Engine and Tonic where I recounted the story of how me, Beth Head of Engines and Basil the dog rebuilt the 1500 engine over winter, ready for the NEC show in March. Disappointingly, we’ve already blown it up.

Whilst heading down to MG Live! at Silverstone where the car was going to be on the MGCC Young Members stand representing under 30s within the car club, I felt a loss of power as I went to overtake a BMW. Well, the BMW wouldn’t let me back in, and the water temperature gauge shot up to over 130*C. I coasted in lane one of the smart motorway (no hard shoulder to stop on) and ditched the car into a verge between the barriers.

A call to the RAC reporting head gasket failure was duly made, although I was aware it was possibly more serious as the engine wasn’t even turning over. After an hour’s wait, Highways England arrived to tow me off the smart motorway as the RAC couldn’t recover me where I was. This meant slowing that section of the M1 down to forty and closing two lanes of traffic! I got a ride in the back of the 4×4 as they pulled Gem to the next exit, leaving her in the first laybay.

Not wishing to miss my day at Silverstone, I kindly accepted a lift from Lorraine Noble-Thompson of the Caledonian Centre who was already at Silverstone, just ten miles away! I had a quick look round the show, chatted with some delegates from MG Motor India, watched Richard Woolmer throw his number 138 Turner through Becketts in the Equipe series, caught up with the Indian film crew (that’s a different story…) and was briefly interviewed by my friend and fellow young membership ambassador, Wayne Scott, who was running the live stage.

A blast back down the A43 in Lorraine’s Sunspot TF to where Anthony from the RAC was just arriving with his truck. He loaded the Midget on to the flat bed, and off we left destined for the workshop in Walsall. He was very interested in young people owning classic cars, and I recounted some of the funnier times I’d broken down – anyone with a classic car will know this is to be embraced as part of classic car life, and when you have several like me, you’re at the side of the road a lot! We tucked Gem up in the workshop, leaving her a few days to think about her actions!

On returning to the garage I was quick to strip the block down. The new 4-2-1 exhaust header meant I could reach the b*stard nuts underneath the manifolds more easily than with the standard cast iron equivalent, and pleasingly I was able to remove the inlet manifold in one piece without disturbing the carb linkages and gaskets. With the manifolds removed, I could see there had been a water leak from the bypass pipe that passes beneath them, and there was infact a 1.5mm hole in the pipe on further inspection. Could this have contributed to the overheating and HGF?

The gasket itself wasn’t in terrible shape, although I’m fairly sure it had indeed blown between a water way and No1 Cylinder. The engine was still seized though, so soon the sump was off. I stripped each big end cap in turn, although freeing off No1 gave me plenty of answers (and a freely rotating crank again.)

Luckily, the crank pin appears to be relatively unscathed. I decided to remove all the pistons and inspect for further damage, which turned out to be a good choice as the first compression ring on number one piston had shattered in several places.

So my theory goes such: The water level had decreased through the leaking hole to such a point that it allowed the engine to overheat, blowing the head gasket and such heat around no1 caused the ring to break and meant that the oil film broke down and allowed the bearing to become damaged, seizing the engine as it suddenly stopped very hot, as I coasted to a stop.

I’m not an expert though – so anyone with alternative theories, please contact me in the comments here or at LittleBlueMG@gmail.com.

Rebuild will be a straight reverse of dismantling with new rings, bottom end bearings and head gasket. I think for safety I’m going to add an oil cooler, too.

Bloody thing.