looking for x1/9 fi thermostat housing and 02 sensor

jcstuckinmuck

Daily Driver
Hi all sorry ive been away for a while,have been sooo busy, now trying to get on with the carb to fi conversion on my x1/9,does anyone have a good fi thermostat housing and sensor that i could buy, also looking for o2 sensor for exhaust too, iam on the other side on the pond uk, i have looked at midwest site, none available, any ideas, thanks guys john
 
If no one else responds, I'll look for my old one. Pipe ports are re-tapped to NPT so that alternative pipe fittings (AN) could be used. Regular pipe fittings will also fit.

I wouldn't ever use a used single wire O2 sensor, they are supposed to be replaced at 30K intervals. Single wire (non-heated) sensors have a limited life span. Should be easy enough to locate one in the UK.

X19-0046b.jpg


This should be in FS&W
 
The X1/9 Bosch L-Jetronic fuel injection uses a coolant temperature sensor that the Bosch literature calls NTC II [2]. NTC stands for Negative Temperature Coefficient, which means that the sensor's electrical resistance goes up as the temperature goes down. II [2] indicates that it is for coolant; the temp sensor for intake air is incorporated into the AFM (air flow meter) and that is called NTC I [1].

If you are having difficulty acquiring an FI thermostat housing, the coolant temp sensor car be located elsewhere in the cooling system, as long as it is within the engine loop and not the radiator loop. FI cylinder heads have two threaded ports into the head's water passages, one for the sending unit for the coolant temp gage on the instrument panel and one for the thermo-time switch that helps to control the cold start valve. They also have another flat spot that looks like it could be drilled and tapped to add a third sender/sensor. See Jeff's "FI head for sale" post with pix: https://www.xwebforums.com/forum/index.php?threads/fs-x1-9-1500-fi-cylinder-head.35348/#post-306699
 
Hi guys thankyou so much, thats very interesting, on the other sensor position and o2 sensor details, so the thermo time switch would have to be tapped into the head or mounted in different position.

Also does anybody have a picture of where the thermo time valve is and the pipe location to and from. and thats the other missing part i dont have either, as for the rest of the injection kit i think i have.
Also i will have to modify my fuel linkage as its different to the carb.

Thanks lookforjoe, yes please i will have that thermostat housing, pm me the price and delivery to uk
Kind regards john
 
Hi guys thankyou so much, thats very interesting, on the other sensor position and o2 sensor details, so the thermo time switch would have to be tapped into the head or mounted in different position.

Also does anybody have a picture of where the thermo time valve is and the pipe location to and from. and thats the other missing part i dont have either, as for the rest of the injection kit i think i have.
Also i will have to modify my fuel linkage as its different to the carb.

Thanks lookforjoe, yes please i will have that thermostat housing, pm me the price and delivery to uk
Kind regards john

Sorry I missed your reply, did you find one or should I look for this still?
 
If I'm going to send this to (England/Scotland/Ireland/Wales?) you may want to review what else you need - I have most of the injection components having stripped mine when I converted to Volvo LH2x :D
 
As it has been mentioned, so long as the coolant temp sensors (TempTimeSwitch, FI temp sensor, gauge sender) are in the coolant passages, they could be mounted pretty much anywhere on the head/T-stat housing, even block if needed. There may be slight variations in temps from one spot to another but it won't be enough to make a significant difference on these old design systems. So depending on what parts you find, you can decide where to mount them accordingly.

I'm guessing if the pipe connections on Huss (Looking For Joe) T-stat housing have been tapped for thread in fittings, they will be the US standard "NPT" and not the British pipe thread (they are different). So you will need to get US type fittings or possibly retap them (if there is enough material).

I agree with him, you are better off buying a new O2 sensor, perhaps look online. The TTS on the other hand is quite expensive new so I would try a used one, they are rather durable so a used one should be fine.

There is no "pipe" related to the TTS, if I understood your earlier comment correctly. The sensor threads directly into the head. On one of the pictures from the earlier link, here are the TTS and dash gauge/light senders (left and right respectively), red circle. And a extra boss where another sender was once installed (these heads changed a few times over the years, so there are different arrangements possible), blue circle:
x1500head01.jpg
All three sensors could be located on these three spots, or any/all of them could be on the T-stat housing. Fiat located them differently at various times. So there really isn't one 'correct' layout.

I'll try to get a pic of a "FI" T-stat housing later today.
 
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This is the one I have for sale if you still need one, also has a new dual action SuperStant t/stat installed (Housing modified for additional sensors):

9-DB81-CA8-1639-4860-B371-51-A355-BC2-F62.jpg


Accepts NPT 3/8" and 1/2" pipe thread fittings (use teflon tape or plumber's pipe thread sealant), so you can adjust the feed & vent hoses to the tank, based on what you have available. Standard (3/8") heater hose is a good fit over 1/2" (ID) copper pipe (smaller of the fittings shown). I can provide TTS, ECT & adaptor fittings I had made if needed.

0-B6-AAC13-531-A-4-FA8-92-EE-35-B0-C685-F53-D.jpg


without the adaptor for the TTS, it will sit too far into the coolant passage, IMO.

392-B2447-123-D-4966-80-CF-BC177-AC45116.jpg
 
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Had a chance to take pics of one of my T-stat housings (below). The same as Huss (above) before his was modified, just for comparison. As you can see, one sensor for the FI coolant temp. This is a M12 fitting, and the two on the head are M14 (however the sizes may have changed over the years).

017.JPG 018.JPG
 
While on the topic of stat housings, it's very common to see erosion in the coolant hose nipple surfaces on these. As long as it's not bad enough to create an actual hole in the nipple wall, this condition can be easily remedied by first thoroughly cleaning the nipples (bead blasting preferred for "bite" but a non-residue chemical cleaner is good, too), then using any good epoxy product to fill in the divots, shape before it hardens, then sand to smooth and round after it hardens.
 
Dan, I guess my crusty example illustrates the need for this fix. :(
You should see the rest of the car this one came from.
 
As it has been mentioned, so long as the coolant temp sensors (TempTimeSwitch, FI temp sensor, gauge sender) are in the coolant passages, they could be mounted pretty much anywhere on the head/T-stat housing, even block if needed. There may be slight variations in temps from one spot to another but it won't be enough to make a significant difference on these old design systems. So depending on what parts you find, you can decide where to mount them accordingly.

I'm guessing if the pipe connections on Huss (Looking For Joe) T-stat housing have been tapped for thread in fittings, they will be the US standard "NPT" and not the British pipe thread (they are different). So you will need to get US type fittings or possibly retap them (if there is enough material).

I agree with him, you are better off buying a new O2 sensor, perhaps look online. The TTS on the other hand is quite expensive new so I would try a used one, they are rather durable so a used one should be fine.

There is no "pipe" related to the TTS, if I understood your earlier comment correctly. The sensor threads directly into the head. On one of the pictures from the earlier link, here are the TTS and dash gauge/light senders (left and right respectively), red circle. And a extra boss where another sender was once installed (these heads changed a few times over the years, so there are different arrangements possible), blue circle:
View attachment 16647
All three sensors could be located on these three spots, or any/all of them could be on the T-stat housing. Fiat located them differently at various times. So there really isn't one 'correct' layout.

I'll try to get a pic of a "FI" T-stat housing later today.

These days we have much better options available to us than what was economically possible in the 80's. When I put a euro (carb) head on my Fuel Injected X/19 I also faced the issue of missing sensors. That said, all of these sensors (so the auxiliary air sensor and the thermo time switch) are essentially completely separate from the operation of the actual fuel injection. Essentially, in the early Jetronic systems, the cold start system is completely separate from the fuel injection system. As a result of this, you can easily come up with a more modern alternative that doesn't necessitate so many sensors having access to the cooling system. I simply used the sensor that drives the temperature gauge to provide an input to a microcontroller (Arduino mini). This is then responsible for controlling the cold start injector (replacing the function of the thermo time switch) and driving PWM controlled idle valve (to replace the Auxiliary Air Valve).

The result is something less bulky with fewer temperature sensors and which is more reliable and flexible.

Cheers,
Dom.
 
Hi sorry for the delay guys, great info here, which helps alot, yes iam looking for other parts, which is the t stat housing with sensor if posibble, throttle linkage to plenium chamber(over cam box, aux air valve and hoses from manifold chamber to to aux valve to the intake boot and it looks like there is a plastic nipple on the underside of the intake boot which connects cranckcase to inlet and one for aux air valve pipe, and sensor for the head(for ecu temp),also fuel pipe from fuel filter to injection rail pipe, this pipe i belive runs behind the coolant tank.

I have a new o2 sensor so thats fine, iam going to try for external fuel pump and see if that works, iwill post the progress as i go along which will be here in this post https://xwebforums.com/forum/index.php?threads/carb-to-injection-progress.35672/#post-309138
 
Another thought just occurred to me.
I recall you asked about the carb cooling blower/fan. Does your head have a second sensor on it to control that cooling fan to the carb? My '79 (US spec) carb head does; it looks much like a temp sensor for other things, but it's fairly large and has two wires to it. It is actually a switch that connects those two wires at a specified temp, to turn the blower fan on. If you are removing the carb blower fan (I think you said so), then that switch can be removed and another sensor mounted there. You might have to get a thread size adapter or slightly modify the hole/threads. But it is a easy location to have coolant temp access.

EDIT: I might be confusing the carb fan switch and a US smog-device temp-switch (goes to something they call a "gulp valve"). So your head may not have that one. The switch for the carb blower might be on the carb itself. But look to see if there is a second temp sensor/switch of any type on the head that can be replaced with one you need.
 
Hi sorry for the delay guys, great info here, which helps alot, yes iam looking for other parts, which is the t stat housing with sensor if posibble, throttle linkage to plenium chamber(over cam box, aux air valve and hoses from manifold chamber to to aux valve to the intake boot and it looks like there is a plastic nipple on the underside of the intake boot which connects cranckcase to inlet and one for aux air valve pipe, and sensor for the head(for ecu temp),also fuel pipe from fuel filter to injection rail pipe, this pipe i belive runs behind the coolant tank.

I have a new o2 sensor so thats fine, iam going to try for external fuel pump and see if that works, iwill post the progress as i go along which will be here in this post https://xwebforums.com/forum/index.php?threads/carb-to-injection-progress.35672/#post-309138

You can message me about the housing, if you want it. I need an address to figure out shipping. The ECU temp sender is the one I have shown, it locates in the T/stat housing. I may have the fuel pipe, I'll check - however it will likely be prohibitive shipping, simply due to the size box needed to pack it. Aux air valves I have, not the hoses. They crack with age.
 
Another thought just occurred to me.
I recall you asked about the carb cooling blower/fan. Does your head have a second sensor on it to control that cooling fan to the carb? My '79 (US spec) carb head does; it looks much like a temp sensor for other things, but it's fairly large and has two wires to it. It is actually a switch that connects those two wires at a specified temp, to turn the blower fan on. If you are removing the carb blower fan (I think you said so), then that switch can be removed and another sensor mounted there. You might have to get a thread size adapter or slightly modify the hole/threads. But it is a easy location to have coolant temp access.

EDIT: I might be confusing the carb fan switch and a US smog-device temp-switch (goes to something they call a "gulp valve"). So your head may not have that one. The switch for the carb blower might be on the carb itself. But look to see if there is a second temp sensor/switch of any type on the head that can be replaced with one you need.
My 74 engine has a vacuum thermo switch in that port and my 79 engine has the same switch that you described. The carb fan switch that came with the car attached to the RR carb mounting stud.
 
Well iam decieding to no bother with the cooling fan, as i thinks it not hot enough here in the summer, who knows, i will see what happens
 
Hi lookforjoe, parts have arrived and i must say i am very happy with the t/stat housing and parts, will be fitting tomorrow hopfully, a big thanks
 
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