New thermostat housing, etc., '99 XK8

The car only has about 75k miles on it, and has been well maintained. Engine tensioners long since replaced, no rust. It’s a great car, and I plan to keep it. My mechanic says the thermostat housing and water crossover piece are looking tired, and recommends replacing them.

I see that SNGB has an “Aluminum Thermostat Housing Repair Kit” available. Aluminum sure sounds better than the original plastic! However, they don’t show a crossover pipe. The forum posts (several years old) indicate some fastener-access difficulties, but that doesn’t scare me too much, and I’m thinking of trying to do this job myself.

I would love to hear any comments, experiences, etc., either on the job itself or on the parts.

Bob Frisby
Boise, Idaho
XK8, XKE, and other old Brit cars

It was years ago the I changed over to the aluminium housing. At the same time replaced all hoses and crossover. If I recall maybe one of the fasteners was a bear to get to. I think I used 1/4" drive with swivels
is doable.

Easy Peazy, The cheapo plastic housing was a joke. Your lucky it didnt crack or worse.
Once done,your set for life.
Good luck


As I recall (it was a few years ago) I replaced the thermostat housing (with alloy), water pump (with metal impellor instead of plastic) and crossover pipe at the same time. There are two 8mm bolts that are difficult to access. I bent two 8mm wrenches at 90 degrees, one open ended, one ring, and used vice grips on the other end to get some leverage. Used the ring end to break the bolt free and the final tightening, and the open ended for the rest - you can’t use the ring throughout as an obstruction prevents you removing the ring once the bolt is part way out. There are youtube videos that show what to do. Good luck!

Same here as Davidxk. First time i was removing the manifold to replace the water hoses under it but I later decided to replace the housing with the alloy one and heated up an 8mm spanner and bent both ends. As David says it’s a useful tip that you can’t use a ring all the way as it jams itself. The alloy one has been on for about 10 years or more with no problems. The cross pipe is plastic and i replaced that and the temp sensor together.