cooling problems AC, FI-engine and other issues

[Roger27TBB]

Hi all,
yesterday i made the 2. test drive after renewing several parts like radiator, thermostat, front suspension with bearing kits for hub and strut top, calipers ,discs and brake pads.
The AC kompressor runs for the first time since i have the car (3 years), maybe much longer, too.
But there is no cold air coming out the vents. The trouble is the leaking heater valve. It leaks through the piston when the AC is on. There is also a puddle under the car in the middle. Don`t know if the heater matrix is also leaking. There are no spare parts for this available (i read the posts regarding this) and searched in the net.
After driving i measurded the temperature on the exhaust manifold and body shell opposite with a infrared temp measure gun. It shows 660-752 °F on the manifold and 140-180 on the body. The temp indicator shows half and a little over half. At last i suppose that the exhaust sytem with CAT is may be blocked because it´s like before changing the radiator.
How warm does your front wheel nuts become ? I measured 100-110°F.
My turn indicator is working to slow (3 to 5 sec. frequence). A new relay hasn`t helped. Could it be the connection to earth ?
Is the throttle cable the same as for the TR8 ? It looks alike.

regards
Roger27TBB

[FI Spyder]

Can't comment on AC as my freon is long gone and I don't need it where I am anyways. Puddle of what under car? The turn signal relay relies on a certain amount of current going through it to activate it. Any resistance in the line will reduce that making it slower. That means not only ground (which is all people talk about) but any connection before that. That means bulb to bulb holder or wire connection. These connections are open and exposed to air contamination (SO2 etc.) with water vapour in the air will corrode over time. It doesn't take much, we're just overcoming 12V here. Clean connections also mean brighter burning bulbs. Some people change to an electronic relay but that's not addressing the issue, just covering it up.

[FI Spyder]

Can't comment on AC as my freon is long gone and I don't need it where I am anyways. Puddle of what under car? The turn signal relay relies on a certain amount of current going through it to activate it. Any resistance in the line will reduce that making it slower. That means not only ground (which is all people talk about) but any connection before that. That means bulb to bulb holder or wire connection. These connections are open and exposed to air contamination (SO2 etc.) with water vapour in the air will corrode over time. It doesn't take much, we're just overcoming 12V here. Clean connections also mean brighter burning bulbs. Some people change to an electronic relay but that's not addressing the issue, just covering it up.

[Roger27TBB]

Thanks for reply FI Spider,

it is coolant water under the car.
What about the temperature on the exhaust manifold and body and the wheel nuts ? The wheels are running free when i jack up the car.
I´m rather sure the engine heat is to high. Tomorrow i want to check the heater matrix with dismantling the heater valve and change it to a normal one that fits to the core from another car or make a closed circuit with connecting both ends with a rubber tube.
I also will improve the throttle cable as the TR8 cable looks like with another rubber tube around and
make it stiffer. The line of the cable loops also to curvy and is to loose at the end so that i had scary
moment yesterday during the test drive. The engine speed suddenly went up to 5000 or 6000 rpm. What a noise !!
Don`t know if the gear was jumping out. In this situation i shut down the engine and restarted again.

[Beans]

... it is coolant water under the car ...

Where exactly underneath the car?

[HDRider]

The heater control valve can be replaced by one that fits a Volvo. Unfortunately that part seems to be discontinued as well.

The matrix is different from the non-AC unit. No one has found a substitute that I know of. Fortunately they do not often fail. You should back-flush it with low pressure water though.

There are lots of other water-flow valves you you might be able to install on the engine side of the firewall. Of course you would need a separate control cable for it.

Edward Hamer
Petaluma CA

[skertonman]

I suspect the puddle under the car is condensation draining away from the A/C unit. All modern cars have a similar puddle when they are stationary and running the A/C.

The A/C units have specific drain outlets to drain the condensation away.

It will be clear water if you take a close look at it.

[saabfast]

Re the front wheel nuts, 100F (38C) is not much if you had been for a run. Remember they are effectively connected to the brake disc which gets much hotter than that under braking. The hubs and wheels do get hot from that. If you are concerned about the bearings just make sure they are not adjusted up too tight (you should just feel a little movement in the wheel rocked from top to bottom) and do not rumble or squeal when driving. The grease should be high melting point bearing grease so will not be affected by the temperature.

[FI Spyder]

(you should just feel a little movement in the wheel rocked from top to bottom)

My quandary at the moment. I have a slight wheel wobble above 60 mph and when reversing or going over rough ground (like driving over grass to get to parking at a car show) you can feel some slop through the steering wheel yet when wiggling steering wheel at rest and observing tires there seems to be no play in system. I thought there might be some play in steering box that gives this effect. Last year I readjusted hubs to speck (5 foot lbs then back nut off one flat) . Currently doing wheel rotation (and painting alloys and derusting wheel nuts) and the front wheels seemed to have a lot of play when grabbed top to bottom. Readjusting to speck still left what feels like a lot of play. I thought there might be some wear in bearing (they seem/look fine otherwise). After new tires in 2007 steering was silky smooth for about 8 years with this slight wobble just in last few years that I haven't pin pointed yet. Backing off wheel nut 1/2 a flat minimizes this still leaving some play. Is this enough to prevent any problems with it being too tight?

[Hasbeen]

Did I read that right Spyder. Are you really running tyres that are 10 years old.

I wouldn't run tyres that old on the old box trailer I use for runs to the dump.

Hasbeen

[HDRider]

I had a wheel wobble problem recently. Tires are new and double checked on the balance. A new steering rack removed the problem. The gear/rack was worn in the straight ahead position enough to allow the rack to osculate.

Adjusting the tie-rod ends to move the rack to one side or the other changed when the wheels would wobble. In my car it meant that they would wobble in a slight right turn at speed. Touching the brakes lightly also removed the shake.

Edward Hamer
Petaluma CA

[Roger27TBB]

Thanks all for reply.
Today i was searching for a 16mm diameter rubber tube/hose or a cobber core that measures 16mm in a DIY Superstore to mount it instaed of the valve but without success. There were only diameters 15 or 18 for cobber core and 3/8" to 1/2" inch and smaller or bigger and no pieces to connect used for plumbing or waterhoses for the gardens. So i will order a set of hoses to have a replacement and a heating valve that fits.
I checked the adjustment of the hub twice, to get sure that it`s not to tight, as written in Haynes Workshop book.
I don`t have wheel wobbles as i remember. The tyres are not older than 4 years.
The puddle of water was coolant water and no clear water (position is under the gearbox).
At this time it is my biggest challenge to get the AC working and the engine cooling not leaking, the
turn signals flashing faster and getting the MOT the during the next two weeks. At the moment my holidays begin, time enough for repairs. But in the last week i will have a first visit to England to the event of British Cars in Gaydon from the 30th of June to the 2nd of July. Travelling by plane and train. Hope to meet some TR7 enthusiasts .
How can i add pictures to the post ?

Greetings
Roger27TBB

[saabfast]

For the turn signals I would recommend replacing the flasher unit with an electronic one. The standard item is very dependent on the generated power and tends to slow at idle. The electronic one is easy to fit (uses same connector but some need an extra earth), cheap, reliable and the flash rate is constant.
The TRDC annual meeting is at Gaydon 1st/2nd July so there should be plenty of TR7/8's there (including mine), look forward to seeing you there.
To post photos you need to use an external host such as Photobucket (its free), then click on the 'img' link at the top of the dialogue box and paste the link between the notations.

[Beans]

... The puddle of water was coolant water and no clear water (position is under the gearbox) ...

There are a few coolant connections near the gearbox, these are the options;
1. One of the two connecting hoses between engine and heater (so bulk head area) is leaking on top of the gearbox. And as such dripping down from the gear box;
2. There's a drain opening for (rain) water on top of the transmission tunnel (underneath the heater units fan). But rather difficult for coolant to exit from there ...
3. The heater matrix itself is leaking, and the coolant is finding its way to the top of the gearbox ...
Try my weblog using the filter "heater" and "Restoration DHC" for some more info and pictures for the AC heater.
God luck hunting

[FI Spyder]

Did I read that right Spyder. Are you really running tyres that are 10 years old.

I wouldn't run tyres that old on the old box trailer I use for runs to the dump.

Hasbeen

They are ten years old and still seem to be good. I rung them out on the Duncan Motor Sports race track last year and they did a yeoman's job of it. I wouldn't take them to the edge on a public road anymore even though they still look like new and have plenty of grip. They're Kumhos. I do know what you are saying, the tires on my Integra were getting on (not sure how old they were, probably about the same). One winter I noticed they had little grip in the wet with me sliding a bit to far into the intersection on anything but pretty gentle braking. I replaced those Michelins a couple years ago. I use Maguiar's Endurance tire dressing and that seems to prevent any age cracks.