I had a fortuitously-timed failure of my heater valve in that it happened in my driveway rather than out on the road. Coolant started pouring into the engine bay from inside the valve. But I REALLY did not want to take a chance on the standard heating/twisting/ bashing technique to remove the valve at substantial risk of damaging the notorious firewall coolant pipe, so I started looking for an alternative fix. Turns out the new heater valve I purchased from Barratt’s looked virtually identical to the aged original version, and further discovered that it’s easy to dismantle, and even better, the parts are interchangeable. This raised the prospect of swapping the inner parts (bearing mechanism and diaphragm) while leaving the corrosion-welded valve body stuck in place.
To repair, drill out the rivet on the top of the valve and twist the 2 halves apart. Then reinstall the new diaphragm/bearing assembly back into the original position in the old valve body using a C-clamp and socket to compress the 2 parts together.
Pretty easy to do, and I’ve driven 50 miles with no leaks, so I’m going to declare success and hope it works for others. Also allows you to save the heartburn of pipe replacement for the time you’re actually prepared to do it, like when the car is dismantled during a restoration, or in my case, probably never.
Steve,
Are the copper pipes already installed? If it was me, I’d call the PO’s mechanic and find out why he used copper instead of the readily available SS pipes, which are still pretty cheap (about $40 apiece). I suspect the replacements are made of stainless for a good reason.
Tim
If you are so worried about damaging the pipe that you don’t want to remove the old valve, I would suggest you are setting yourself up for a future disaster. I had NO problem removing the valve from my 20 year old pipe, and installing a new valve. If you have so much corrosion you cannot remove it without damaging the pipe, then you are living on borrowed time. It WILL fail at some point, when you least expect it.
You’re missing the point. The conventional wisdom you reiterated is probably true for cases of serious pipe-rot, but I think there’s more to consider here. If the valve is being replaced because the heater doesn’t work, such as it being seized, or full of debris (but not leaking), then swapping the valve parts will temporarily fix the problem, although it’s probably a good idea to move “pipe replacement” to the top of the task list.
In my case, the heater works great, there was no rust in the valve or lines, plenty of flow, but the diaphragm was torn and therefore dumping coolant into the engine bay. There was no evidence of rotting pipes, and I’m thinking galvanic corrosion fused the aluminum valve to the outside of the 55 year old steel pipe. There is a potential problem, however, with wrestling a corrosion-welded valve body off of the pipe end, even if the pipe started out in decent shape. This risk is damaging the pipe surface by scoring or gouging so that the new o-ring will no longer seal, creating a new, totally unnecessary repair. Again, replacing the inner valve parts gets you back on the road in 30 minutes, the leak is repaired, and assessment of the pipes can be performed at a later, more convenient time.
I recently replaced the pipes in my '69 OTS. Yes, it was a horrible job, but during the process of replacing them, I developed a real appreciation for the potential damage a leaking pipe (or pipes) could cause.
I’m sure that there are those on the Forum who have experienced firsthand.
Yeah,it had been sitting in my garage for over 30 years after I had stripped it for a repaint, new rubber trim, windshield, top & interior.Then life got in the way.The ends of the pipes protruding from the bulkhead we’re corroded and rusty. I had a lot of trouble getting the heater valve off. I have intended to cut one of the old pipes to see how bad they actually are.
I’m fairly certain the pipes in my car are original, so I’m trying to assess whether to replace them sooner rather than later. Warning signs of deterioration would certainly be good to know. I think you hit on 2 indicators in your car which must be pretty reliable, suggesting that the old pipes are toast. The first being knowledge the car sat up for decades, meaning rust inhibitors in the coolant are long depleted, so there must be deterioration in the steel pipes. Secondly, rusty pipe ends would also indicate that there’s peril ahead, and I’d be interested to see the cross section of your pipes if you get around to cutting them. I think I’m inspired to pull all the tubes off the pipe ends on my car during the next coolant change even though the single pipe I did expose during the valve surgery looked very good.
Galvanic corrosion eats away BOTH metals. And if your pipes are 55 year old steel pipes, you’ve already been living on borrowed time for decades. There is no way they are solid unless they’ve been kept dry for all those years.
Borrowed time for sure.
Some time ago I wanted to renovate the heating circuit on my FHC (valve blocked).
When I inspected the pipes, I was horrified to discover how rotten they were!
Not wanting to face a dramatic leak in the whole circuit, and not being capable to replace the steel pipes behind the shield, I decided to bypass whole the heating circuit.
I feel now more comfortable, although knowing it should be a temporary repair
I am contemplating the same thing for my car. I have no problems so far but since I am in Houston and never felt the urge to turn on my heater in my 20+ years even on colder days. I found rubber plugs at the hardware store that appear would block off the pipes after draining and drying but still allow the hoses to fit back in place for the original type look. I laid one next to a hose in this photo.
David, That certainly looks like a good way to postpone the pipe replacement, but I do alot of winter driving and need the heater, so I’d probably figure out a way to mount some surface pipes on the engine bay side of the firewall. I know this idea been done with hoses, but I think using smaller diameter stainless (or copper) pipes, a clean looking system could be put together, and I suspect it’s already been done.
Regarding further assessment of the existing system, I was wondering if anyone has tried testing the original steel pipes with a significant amount of air pressure (say 100 psi) which would either blow out potential weak spots, or indicate they’re still in fairly good shape. That might allow for some breathing room in the “borrowed time” dilemma.
You can safely assume that if they are rusty at the nipple end, they are compromised through their entire length. Mine looked that way, and it was as well-taken care of as any E type when it came to antifreeze changes. They were junk.
“I’d probably figure out a way to mount some surface pipes on the engine bay side of the firewall. I know this idea been done with hoses, but I think using smaller diameter stainless (or copper) pipes, a clean looking system could be put together, and I suspect it’s already been done.”
Good idea, I also thought of it (annealed copper pipes are soft) but did not do it, not having the tolls and skills.
I would be interested to follow that project.
Tim,
Although I stand by my assertion that replacing the heater pipes is a job from Hell, it can be done and was done by an absolute amateur (ME) and what you are proposing doesn’t sound that much easier to do. Also, I think that it would be difficult to avoid messing up the ambiance of the engine compartment.
Spike
Does anyone know if it’s possible to replace all three of the heater pipes by threading them through the small hole behind the Hazard Flasher relay (in the centre of the dash of a 1971 series 2 FHC).
I will replace the top ‘bent’ pipe for sure, but having bought a set of 3 stainless steel pipes from SNG Barratt in England, I’d prefer to replace them all.
I can get the longest pipe in, by pushing it up and into the top left under the scuttle board, but then pulling it back under the centre brace and getting the ends to go through the firewall looks to be a massive challenge.
Nervous about pulling the old one out and thus committing to replacement.
Any tricks out there?
In searching the archives and youtube videos you will see that you can do this…but before you do anything, make sure your new set of tubes are bent properly. Hold them up against the existing holes and bend as needed. Just did this job a few weeks ago and was surprised at how much I had to bend the brand new set. JS
