I have read through the threads on this and didn’t find my problem. My vacuum stopped working, sort of, last week. It was fine and then one day the pods wouldn’t raise. I spent some time connecting and reconnecting trying to find where the problem was, when I raised the right pod by hand. When I did this both pods came up and stayed up while the engine was running. I drove it around and they stayed up under acceleration as though they were ok, but still wouldn’t raise on there own. The right pod looks to be in pretty bad shape anyway, but I was wondering if it could be some sort of lubrication issue. Any suggestions would be appreciated. Thanks.
I have an S2 non-failsafe. I don’t have a mityvac, Ray at R&D suggested I get one. The thing is, the vacuum is sufficient to keep the pods up, I don’t know if that means that the pods aren’t leaking or not. It’s just that they won’t raise without assistance (well…the right one). The right pod has some pretty bad rust (the left looks OK). I might be able to find someone with a mityvac, so perhaps that would help. I should mention that I have bypassed the cross member for the time being.
My car was the same when I first bought it, you had to start the engine then get out and lift up one of the headlamps. It was a bit more difficult on a slope as the handbrake didn’t work.
I found it was the T piece on the vacuum reservoir leaking, there was enough vacuum to keep the headlamps up but not enough to raise them both.
The cross member reservoir should have no effect in your problem. As I understand it, the reservoir helps to keep the lamps up when the engine vacuum is affected, for example by trying to accelerate up a long hill. As the engine vacuum decreases, without the reservoir the lights would tend to sag.
I don’t have a T, as I took out the cross member, but that doesn’t mean that there isn’t a leak somewhere else. I plan to double check all of the hose clamps, as I’ve ripped everything apart and put it back together. The leaking diaphragm sounds plausible as pods were working and then not working. I wonder if this is fixable or if I should just get a new RH canister? (after I verify that there are no outstanding leaks. It’s somewhat heartening that someone else had the same problem and fixed it.
If you determine that the problem lies in one of the vacuum cylinders, and wish to try a repair, I have an old tech sheet somewhere that describes repairs.
Having looked at a duff one of mine a long time ao I decided it was much easier to buy a new one, even if they are rather expensive.
I would only try fix one of those if they were no longer available.
I think you would have to grind the middle rim off and then somehow work out a way of fixing them back together without welding ((because that would burn the diaphragm).
The only way I could think of would be a big long jubilee clip type thing with a V cross section on its strap.
Or two big brass rings with a multitude of little screws to pull the rings together. A bit like a huge diameter bendix spring compressor.
Frank,
Miles Wilkins of Fibreglass Services has some vac pods in stock. When I?ve visited him last week he told me, he is the only one who actually builds them at the moment. Just give him a call, as he wouldn?t reply to emails.
Juergen
Frank, hopefully you are on the road again with working headlamp vacuum.
The Mitvac makes diagnostics so easy. You can quickly isolate the part which is causing leakage, or check out binding etc. Highly recommended.
My top tip would be to regard the non retun valve into the inlet manifold with some suspection. Petrol soaks into the o ring and softens the elastomer. Dirt and gum also stop the needle seating properly. To test, remove the non return from the manifold and suck through with the Mityvac. There should be non resistance one way and absolutely no leakage in the opposite direction.
OK everybody. I checked all of the lines and retightened the hose clamps and still have the same problem. I’m going to get a mityvac as it will probably come in handy down the road. Question:
I have a Mighty Vac that I bought years ago to diagnos a problem with the air conditioning flaps opening and closing on an old Mopar. It has come in handy a number of times since then.
You may want to start with checking the frame. Attach the Mighty Vac directly to the tube coming out of the front box of the frame. I have one spare frame that looks perfect yet won’t hold vacuum due to a pinhole leak. The Mighty Vac will show you a problem instantly !!!
I recently had a similar problem to yours and I thought the vacuum switch was leaking, while taking it out I decided to change over the pipes on the switch and suddenly everything was fine …headlights jumped up and stayed up!
I recently had been doing some work on the car and I must have mixed up the pipes coming from the switch in the nose cone so if you have changed anything lately just be aware.
The MityVac. This is an interesting tool for sure. I have used it to determine that the one-way valve is ok. If I cap one end and attach the mityvac to the other I can pump up to 15 lbs and it will hold. However when I start moving down the line, I am unsure of the results. For instance, if I cap the left pod and attach MV to the vacuum end, I can’t pump a vacuum of any significance. However, when I remove the cap, I can here air rushing (in?), so some vacuum was created of some sort. My question is, what should the pump do here? Should I see 15 lbs again? I can see that learning to use this tool in all of it’s manifestations could be a life-long experience.
The problem is volume of air you’re trying to shift. The MityVac has a pretty small cylinder volume, but can create pretty good pressure/vacuum. When you use it to test a one-way valve, you’re only evacuating a small volume space, so the MV works quickly. Now compare that to the amount of air you’re trying to evacuate from a headlamp pod. It’s gonna take a lot more pumps of the MV to remove that gas.
I have a 4WD equipped for desert travel, with large tires (huge interior volume of air) that I must air down and then back up depending on the surface I’m crossing at the moment (which can be as often as 5-6 times in a few kilometers). So I use a set of Staun preset deflaters for the air-down, and a low pressure (e.g. 60# max) high volume (dual cylinder) electric pump for the air-up. Each of my large tires can be refilled from 15 to 35# in less than two minutes. Yeah, it’s still a pain in the arse, but imagine what it would be like to deflate each tire by hand, and then re-inflate each tire with a regular high pressure low volume pump.
My headlights work pretty well, except on long climbs at speed, where the car suffers from “Droopy Headlight” - particularly the left one. Back off and it pops back up (but I slow down…).
so if you have changed anything lately just be aware.