Rover SD1, Bloody Coolant

Sigh,This game again. Effie is leaking coolant.

I have had a guts full of doing coolant on this thing. I thought I finally had it sorted but last time I drove her I noticed that the coolant light had come on and the expansion tank was low. I topped it up, but it didn’t stay full after a drive. We had a leak.

I did some investigating; I had a hunch that since I fixed the leak from the waterpump bolt (by moving the crank sensor mount to a different bolt), that it would be coming from the damn under intake coolant pipe. I checked the rear of the engine and sure enough there was some bright green coolant in the back of the Vee. I tried slipping the coolant hose further up the pipe and tightening the clamp down, but it was still leaking. There aren’t many places it can leak that will end up with coolant in the back of the vee.

Under the intake manifold, in the Vee, there is a steel pipe that feeds the heater core. These pipes are notorious for rusting out and causing issues. The biggest issue is that you cannot see the pipe, let alone fix it, without removing the whole intake manifold. Lame.

Heres a spare manifold I have, showing the long, rusty, metal pipe (the lower one. The top, black one, is for early EFI cars and mine doesn’t have it)

Here’s the problem. This pipe would make a good garden soaker hose. Its full of rust holes, and no matter how far you slip the hose along the pipe, it wont go far enough because of the mounting bracket.

My plan was to remove this pipe from the manifold, and use the hex fitting that screws into the intake with a new pipe, and then fit that to Effie. The first issue, is how the heck do you remove a steel threaded fitting that has been in an aluminium thread for 30+ years? I tried with a spanner and lots of penetrating fluid, with no luck. I tried using my weight as leverage, and it didn’t budge. I asked on Facebook what the best option to remove it is, and it sounds like anyone that has done this job before, has had the same issue without luck.

I don’t give up though, and the best option came to me the next day. An angle grinder and rattle gun. Time to get serious.

I used my angle grinder with a thin cutting disk, to cut through the pipe as close to the fitting as possible. It took two seconds. A hacksaw would do the same job, but slower.

I removed the pipe, and then using a 13/16″ spark plug socket, which fit perfect, a long extension and a rattle gun, I beat on it for a minute or two. I did a couple of ugga duggas forward and reverse to try to break the seal, and then bam, it spun off freely. I really need more impact sockets…

It was clear the threads were full of oxidation.

It screws back in again fine, so once its out if the threads are cleaned up, it can be reused.

Funnily enough, the pipe had even more holes on the top side, that you couldn’t see when it was fitted.

The pipe measures an OD of almost 16mm (this is important as the hose that goes onto the pipe needs close to this OD to seal)

and the ID of the fitting is 13.78mm. If it can be reamed out to a smidgen over 14mm, and a 14mm pipe sourced, it could be slipped inside the fitting and soldered in. I need to look at my options for opening up the end of the fitting as I don’t have a lathe. As long as a bead is on the end of the pipe, the hose will be able to clamp down on a 14mm pipe OK. 16mm pipe would be better, but then it would need to be welded to the end of the fitting.

I’m going to put my thinking cap on tomorrow, and see what Bunnings has in the plumbing department for pipe. Copper pipe would be good as it won’t rust, and is easy to work with. It would also be good if I could work out what the thread on the fitting is, as if I can work that out, I could reproduce the whole pipe from end to end. These pipes have been NLA new for a long time, and despite multiple requests to Rimmers, they havent started to reproduce them. The EFI SD1 was the only RV8 engine to have this pipe, as the carb engines have a different design (which is available new), and the Range Rover eliminated it completely.

Either way, I need to sort a pipe for Effie from what I have here, or she isn’t going to the show.