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Sunbeam's 1973 Fiat 125


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Merry Christmas everyone. Hope you’re all having a great time this festive season. 

The poor old Fiat has been somewhat neglected lately.  Our house build depleted the bank balance, and saving up to transform the bare clay into deck, carport etc is seen as a priority by the ministry. 

I did get to the shed the other day though and one thing led to another.

stuff fell off...

7F3F7161-8F6C-42ED-89EF-4F94DB1CAF0F.jpeg.8f62769b2c5f737aad0e65682159a0ae.jpeg

I can now get a better look at the cancer

6FA808EF-A604-4EB3-A0F6-7CC3C90E2946.jpeg.2c171d8f88dead58b7e029d029aea13d.jpeg

the above rot is adjacent to the front chassis gusset and extends right under the radiator support. Also, typically, the wee chin trim thingy is toast:

5BE9D01C-333B-443A-B95F-2CE8693B3C78.jpeg.0dcf828a1858d377e44449bc4f83d306.jpeg

Next step is to take the motor and box out, and clean up the engine bay a bit and get ready for treatment. I’m very tempted to take it to a vehicular oncologist as I’d like to drive it this century. That way maybe I can rip into the MG with my limited spare time...

 

Till next time. Happy new year etc.

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I got bored and put the radiator back in so that I could run the engine up to temperature and have a play. I don’t remember if I had ever done this, but I put the multimeter across the battery terminals to check the volts and they were very high, eg. 17V. There’s a good chance it’s been toasting the battery since the day I bought it. The first thing I wanted to look at was the regulator. Not good. The points thingy was rusted/welded solid

32A289C7-AC60-4DC6-8F1C-A93AAD64C4FE.thumb.jpeg.e9128abdb5e0c8b044a25f3bfc3627d1.jpeg

Also, this wire (on the right in the pic below) is burnt through.

E9B2297D-A061-4E31-9ABF-983A5B295E9E.thumb.jpeg.892bf38074fc939d9c7290107e459d0a.jpeg

Further investigation reveals the big black wire from the battery to the B post on the alternator is melty.(after I peeled off 1km of duck tape “insulation”)

A8796E1D-F688-4742-8838-D6D8DA000BD4.thumb.jpeg.66f86770a92ae174cacc9d94921c978e.jpeg6F395DF4-9279-4AEF-B7F6-70AA2786F19A.thumb.jpeg.880414628d83b564cb9dc86147e33bb9.jpeg

Consultation with the wiring diagram also revealed the Arancio and Grigio wires were on the wrong terminals on the regulator. I don’t understand electricity voodoo very well, so I’m unsure of the implications of this. 
Next I de-soldered the funny little fuse wires so I could unstick the points, clean them up and reset to a 0.5mm gap. Then I replaced the broken wire, refitted to the car with the orange and grey wires in the right place (and some better insulation on the B cable) and gave it another test. The test results were not positive (no pun intended). The voltage bounces a lot but still too high, and after a few seconds some smoke was seen exiting the regulator. I guess the reg is toast (see what I did there?) 

Additionally I have also found a mystery black wire:

261B052B-04A7-47F7-9817-5616A315F5BF.jpeg.5d9b54def385fea56ab990ec4b47ece3.jpeg

sorry, the camera wouldn’t focus on the wire.. The other end, out of the shot, plugs into a spade terminal that emerges from the main loom. The bit in the photo is a very distinctive female plug. I pushed the wire and a spring emerged from the inside. I’m trying and failing to recall where I have seen a plug of this type before. @azzurro?

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  • 3 weeks later...

I have not been able to get this thing dialled in properly. Ages ago I swapped out the carb for one I got from @azzurro. It seemed to go well, with heaps more top end, but I never could get it to idle. On the weekend I swapped my old carb back in to have another play. This one had a kit thrown at it be me more ages ago. It’s still rubbish. For some reason the accelerator pump does not want to work, despite new diaphragm and seals. Also, it now keeps spitting back through the carb off idle. Plus, it only shows 12 inches of vacuum at idle, so I have an air leak somewhere I think.  I have nothing better to do so I stripped them both and am trying to build one out of the best bits of both.

D9D5A7A6-130B-446D-9645-7F9C64641714.thumb.jpeg.50f6f52ae9c4359a5acffa4ace966ad6.jpeg

I am using my original carb because it’s kitted, has all the correct factory jet sizes (and the other one has been bastardised in a couple of places so I can’t swap a couple of items), and it’s presumably only got 72,000 miles of wear. The first thing I was suspicious about was the diaphragm for the vacuum secondary, since it never had much top end with this carb. Eureka moment number 1.

463E8710-F7BF-42F9-8663-B8226566589F.thumb.jpeg.997c5057fee4c1ae5ebdbaadfaced2e0.jpeg

Ripped as. Swapped it for the diaphragm out of the other which was sound but covered in rusty coloured dust. Gave it a quick clean and fitted. Next, all the jets etc got taken out again and every orifice got a good blast of compressed air, which showed up another problem. When I blew through the idle mixture screw orifice, I could see bubbling leakage through the base of the carb body. Closer inspection reveals some micro cracking stemming from some corrosion. JB weld to the rescue (the dark grey in this pic)

148255B7-A3D5-4618-9781-781AF45A3A73.thumb.jpeg.e0db424bd8e4f94fbc193d11f854c0fa.jpeg

Now I have to wait 24 hrs before I can use it. Pretty keen to see if any difference has been made.

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I really want to get to the bottom of why the accelerator pump won’t work. I tipped some fuel into the float chamber and operated the pump lever. Lightbulb moment! It’s pushing fuel back out through the inlet port, which means it must need some sort of check valve, right? Maybe it’s not working... Time to consult the manual again. It’s item 37 in the pic below
71D08ACF-5429-4FDD-AC0F-38DE700031B0.thumb.jpeg.bbd8302cbd7060a2fce98c4ec3282e13.jpeg


Which belongs in the hole on the side of the float chamber as below

15F017AE-CBB2-4A5A-ACAF-D526C09F16B1.thumb.jpeg.7c42ba27628c085cc71358793d01538d.jpeg

There’s a grubscrew that goes in there too to stop the ball falling out.  Thing is, there’s no ball in there. There’s not one in the spare carb either! Lucky my neighbour is an engineer/hoarder and he said he would drop a container of ball bearings in my mailbox, which he did. I have selected a 3.17mm ball, dropped it in the hole, applied grubscrew and tested. We have squirts!

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Good news, bad news. Good news is it starts and runs, and the accelerator pump works, and it definitely feels like the secondary is opening. Bad news, it’s very rich at idle and low rpm. Even with the mixture screw tight on its seat, nothing changes and I’m roosting black smoke and petrol fumes. I’m eyeing up the weber 32/36 DGV on the MG. It has the correct orientation. The fuel inlet is on the wrong side but the hose should reach. It’s set up for a cable linkage but at least the rotation is correct for the Fiat. Might strip it today and give it a cleanout (not run for 20 years) and give it a whirl.

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It’s a good thing I have so much time on my hands. I decided to remove and strip the Weber 32/36DGV from the MG. For a carb that hasn’t had fuel through it for 20 years, it didn’t look too bad. Just some reddish dust through it. I just methodically pulled it apart and took all the jets, aux venturis, emulsion tubes, basically everything that unscrews or can be extracted and then got busy with carb cleaner and compressed air. 
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Researching the way it is jetted, it’s basically exactly the same as a Capri 1600gt and a host of other 100ish hp stuff, so it should work pretty well. It has the same base mount bolt spacing as the Solex carb. It’s a pretty wide thing compared to the stock carb though, so I had to remove the throttle link rod and unbolt the mount on the cam box to get it to fit. Shame it doesn’t fit well, because it’s a really nice carb. Simple, well made, and still available new. Despite having 20+ year old gaskets etc, the car fired right up and I could immediately tell things were 1000% better. If I had the gear to improvise a throttle linkage for it (would also need a longer choke cable) I would love to run this carb for a while, as I think it could work quite well with this engine.  Anyway, this confirms the (original to the car) Solex carb body has something wrong with it. More investigation reveals another leak here:

59EBD0AA-797E-4836-A0FF-57FBCA9670B5.thumb.jpeg.a60bef6d7d8784ff19dbcac3196e7c77.jpeg

                                                                   
The casting is compromised. Then I decided to drag the other carb body out again and repeat the stripping process and put all the best bits in the other one. I’m a bit messy when I’m in the middle of a job.

008ADDE2-68C0-42D4-9143-985D03EDB0CF.thumb.jpeg.03661b0e7ba5adb674d978e2eca6252c.jpeg
 

Refitted to the car, and straight away I could tell the rich idle was gone. I made some idle adjustments, and I thought it could use a bit more advance. I just set the timing with a vacuum gauge because the engine doesn’t have the timing cover on (has the marks on it). Got it to sit at 18” which is very healthy. Went for a thrash down the road and did a plug chop. Excuse focus or lack of...

75ED1AC7-C83C-4E2B-969C-39E6AC82EE42.thumb.jpeg.490f80b5e569e3b4dd843080a4b26c8f.jpeg

looks good to me. I did feel like the secondary wasn’t opening. If you try and open the secondary throat with the lever that the diaphragm works on, I found it had a significant stiction, so I suspect the vacuum diaphragm is not strong enough to overcome it. There is an adjustment screw in a prick of a place under the float bowl that works like an idle speed adjuster on the secondary butterfly, so I nipped that up until it just stops the butterfly from jamming when it shuts. Another quick thrash reveals it has done the trick. Personally, I still don’t like vacuum secondaries. 
 

So there we are. Days of pottering around, I think the stock Solex is running as well as it’s ever going to. It will have to do, because Covid-19 has taken a dump on my earnings. Twin Dellortos, I haven’t forgotten about you, promise.

                                                            

 

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  • 4 weeks later...
  • 3 months later...

Ok, I’m sick of watching this thing rust in my shed. I have started to prep the engine for removal, then I rage quit when trying to undo the starter motor cable and went inside. It’s only 4 degrees outside and I’m not as hard as I used to be.

BTW, to anyone who has done this before, will the engine and box come out as one unit? Quite a short engine bay.. @azzurro can you comment?

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Today I calmly removed the cables from the starter motor, after first removing the oil filter for some better access. The master cylinder and booster are off (master is suspect), and fuel lines disconnected, and exhaust collector bolts have been cracked/now soaking in 5.56.

please enjoy an elevated photograph of the whole collection.
 

5A32ECF5-7D95-42BD-8180-2E3B2CF77424.thumb.jpeg.b2ecd69ac3bfc633711b590308d46c83.jpeg

 

This pic is extra special since it was taken after sundown, it proves that after a year without, I finally have light in the shed. The neighbour came over with his tractor today, and we attached the approved work platform (wink) and I was hoisted up to replace the 3 blown incandescent 150w bulbs with 30watt Philips LED high lumen bulbs. They work very well. Anyway, this is where I finished:

6FF379EC-C5B1-46A9-B31B-83291A8E8B21.thumb.jpeg.43825b53396bdca4dc7fd9f0edd364e7.jpeg
 

Next step is to dive underneath and attempt to undo the driveshaft doughnut, unhook speedo, clutch cable etc. Not looking forward to it particularly since it’s British car spec filth down there. I’ve heard you need some sort of strap tool to undo the doughnut, but unconfirmed. Also need to puzzle out how to get the gear lever assembly out, as it’s not 100% obvious once the shift rod is unbolted. Hopefully I’ll get to it on the weekend, since I actually have work tomorrow and Friday. Let’s see if I still remember how...

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  • 2 weeks later...

Progress.

CD3220E4-8BEB-4503-B3BA-882879C4713A.thumb.jpeg.127fbbc2236e0bbc309d9e63bd0b5728.jpeg

The driveshaft was the first thing to come out. I managed to achieve this without compressing the donut. The UJ’s are good, the hanger bearing itself is good, but the rubber support is chooched. Once the driveshaft is out, it becomes very obvious how to get the gear stick out. 4x 10mm nuts, and it drops out underneath the car. The exhaust downpipe bolts came out willingly (phew) and then by a series of contortions I got the starter motor bolts out. I don’t know if the starter is supposed to be able to come out of the engine bay at this point but I certainly couldn’t.  Next was the lower flywheel cover and the two bottom bellhousing bolts (easy as), and then I wrangled the clutch cable out before psyching myself up for the top bellhousing bolts. I’m glad there are only 2 up there. I couldn’t find the right spanner angle to get them from the top, so I took @azzurro‘s advice and used all my half inch extensions and universal joint with tape on it and you can just get to them from underneath. One of the trickier operations was releasing the speedo cable. I couldn’t unscrew the cable because I physically couldn’t get my fingers on it, so I undid the nut and wangled the whole speedo drive out.  Lucky the gearbox is light, since I’m working alone lying on the floor, so it was fairly simple to pop it off and onto the floor. The engine came out next, I cannot believe how little clearance there is. With the fan clutch touching the slam panel, there is maybe an inch between the clutch and the firewall. I think I’m going to lose the fan clutch as it’s quite noisy. 
Other observations are...it’s filthy. No oil drips but lots of seeps, from both engine and box. Also, I will need a new gearbox mount, and I’ll get a new hanger bearing for the driveshaft.

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Cleaning up some tools today, I couldn’t resist playing compare the gearbox.

                                               3B7204D9-D638-4E9A-80F7-7E32DE92C907.jpeg.4db3042aee9203b481a449db2be7b508.jpeg

4 speed on the left, 5 on the right. Speedo drives are on opposite sides, and clutch mechanisms are also reversed, but that’s just a bell housing swap away from happiness. I did notice something a bit off about the crossmember still attached to the 4 speeder...

                                              764EBBBD-D822-446D-AF8A-7EDD971AA4BE.jpeg.94fe682707bd9739755e1bf3d6d633e1.jpeg
look at the left of the pic... it’s bent! Further investigation revealed a corresponding ding in the chassis, so that will need fixing too.

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If the return of the Fiat is imminent, I should get onto the sundry jobs I need to do before reassembly. The bumpers are one such job. They have a lot of surface rust on the inside (ok, deep surface rust).  I removed the brackets and overriders after some soaking time in crc. One bolt is still fighting me. 
                  574EEF0B-EA6D-4CA0-86EA-E4FB08777D81.jpeg.7d50d55a0142fe36fed32b6566b3347f.jpeg
 

With all the obstructions removed I can wire brush the worst of the rust. I can’t see myself being able to get it right back to clean metal. Suggestions for a good rust killer and sealing coat are welcome. 
                   0777AB06-5929-4C8F-BE27-FEDBA9ADBC28.jpeg.b2a2835940a91212809efdbfda2c46e4.jpeg
Grot!

 

 Once the insides are cleaned up, I can tackle the shiny side. The chrome isn’t perfect, but serviceable. There are marks where the overriders were but I’m hoping a polish will mostly hide them. I want to leave the overriders off permanently because I much prefer the look. 
 

Share bumper rejuvenation tips with me in the discussion thread

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  • 3 weeks later...

It’s coming home soon! As soon as I can get a trailer, good weather and some time organised. 
I have ordered a swag of miscellaneous parts from fiatparts.co.nz. I also ordered a refurbed bosch alternator for a 124 Spider from Rockauto with a view to going internally regulated.

 I am also dreaming of some new wheels. So a Poll is in order.. 

Panasport (minilite style) 13x6, +10 offsetFF5B968A-4FDB-4BA7-A762-23270BFAB864.thumb.jpeg.488a6b30dc829ae8c9ab20136613ce79.jpeg

Reproduction Cromodora CD30 (available only in 13x5.5) +7 offset, which is the same as the stock steels I think215B6355-7404-4144-B8E1-4F629D1C07FB.thumb.jpeg.88104328f2be17fafa89df6751ea1eb2.jpeg

OR Repro CD66 (13x7) +10 offset.0BF9B727-72F5-44F0-9DAE-D3C0B9DDC7E1.thumb.jpeg.86182e8e9fb0bcb9fcb032965aaea12b.jpeg

I have a favourite, but I’m interested in your thoughts.  

 

 

All 3 sets are available currently on special from Midwest Bayless and would be $1400 landed (plus local GST probably). A bit ouch, but the cheapest I have found on the internet.

If any of you have a lead on local (NZ) wheels I’m all ears too.

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Last two bolts on the rear bumper brackets would not budge, so drastic action was needed.

masked around the vicinity 97CF5F56-E6C4-41DC-A850-382943B68FC5.thumb.jpeg.0bdb1593ece80e0a0985ac0482f4ae2a.jpeg

 

VERY carefully ground the head down, and then whacked it through with a punch.

F37B053F-6443-4D8C-B39A-F32BAC7B71EA.jpeg.1e6c38c848079097c4870dcd41ce3c26.jpeg

The remains pulled out easily with pliers. Now I have to find some more bumper bolts.

 

One of the brackets is very bent also:

8E0DEF0F-E7CF-4995-9C0B-5B028EFC5709.thumb.jpeg.774987b1c630cf648ddb6bb777c8e57b.jpeg

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