General My 5ino's transatlantic adventure

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General My 5ino's transatlantic adventure

The flange on the 28IMB is thicker on one side so you need a slightly longer stud nearest to the rocker cover. They do not have part numbers.
I have repaired a couple of Bakelite spacers recently where they have been chipped by forming a sort of mould with masking tape and using JB Weld then dressing it up when it has set hard.
Thanks again. So how would I go about finding the studs?

What about the studs at the top to fit the elbow? Do I reuse the ones from my 26imb?
 
Thanks again. So how would I go about finding the studs?

What about the studs at the top to fit the elbow? Do I reuse the ones from my 26imb?
I may have a spare stud. The elbow is fixed to the carb with bolts which I also have.
 
I may have a spare stud. The elbow is fixed to the carb with bolts which I also have.
Hey Toshi,
Thanks a bunch. So I found a local hardware store where I can get the M6 bolts for the elbow to top of carb mounting: M6-1.0 x 60 mm

Now I'm stuck finding the correct pins to connect the carb to the engine. I believe one is M6x57mm and the other is M6x72mm? is that right? If so I think I would need that spare longer one (y) Also, what. nut am I supposed to use, is it an m6 or m8?

Last but not least I'm missing the carb to elbow gasket, I thought I had it. Is this the correct number: 4296087
I might have to make my own since everyone stateside charges crazy prices for it.
 
Thanks again. So how would I go about finding the studs?

What about the studs at the top to fit the elbow? Do I reuse the ones from my 26imb?

Seeing your in the US. when i did my carb modifications, https://belmetric.com/studs-and-rods/
Belmetric was the only place that had what i was looking for.
I normally order from Mcmaster Carr, but their threaded stud selection is slim pickings.
 
Seeing your in the US. when i did my carb modifications, https://belmetric.com/studs-and-rods/
Belmetric was the only place that had what i was looking for.
I normally order from Mcmaster Carr, but their threaded stud selection is slim pickings.
Thank you. Just looking for confirmation as to which size the two different studs are supposed, hopefully someone can chime in!
 
Thank you. Just looking for confirmation as to which size the two different studs are supposed, hopefully someone can chime in!
Ding dong, I am chiming 😀
The long stud is indeed 72mm long and has 12mm of M6 thread one end and 18mm at the other. The nuts are M6 deep nylock nuts. By deep it means they have a longer body than standard.
7D7D944E-3B1F-46A4-A947-9F4536407B5F.jpegBBAF3D7E-DCB6-4CCB-9418-EB2956A8FB04.jpeg
 
Ding dong, I am chiming 😀
The long stud is indeed 72mm long and has 12mm of M6 thread one end and 18mm at the other. The nuts are M6 deep nylock nuts. By deep it means they have a longer body than standard.
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Hey Toshi, thanks for sending me the info. I actually didn't see your reply until today but found some pics from a polish website that showed the two different studs for the 126. I was able to find something similar on amazon.com, and ordered m6x70mm to replace the current stud. It seems to be perfect. The only difference is I went with what the Fiat 126 manual shows; m6 nut + washer + split lock washer. It took a lot of time to remove the old stud...but I think I got everything back on there.
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I was wondering, for the choke cable, whats the purpose of the nut closest to the cable entrance? I can't remember if it's supposed to pose some resistance against the cable so that the choke lever has a little resistance as well?


While I was in there, I had a BCD fuel pump I picked up a couple of years ago I wanted to install. It seems like the current pump had no support-to-engine gasket, but they used red gasket maker? Hopefully it's not a sign somethings up. I had two washers with the new pump. I put the thicker one on the bakelite to fuel pump side. Is this correct or does it matter?
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Don't worry, that inlet fuel line is not attached yet as I need to figure out if I will route the fuel return line from the carb back to the fuel pump or just cap it at the carb. Is there any benefit to cap?
 
Hey Toshi, thanks for sending me the info. I actually didn't see your reply until today but found some pics from a polish website that showed the two different studs for the 126. I was able to find something similar on amazon.com, and ordered m6x70mm to replace the current stud. It seems to be perfect. The only difference is I went with what the Fiat 126 manual shows; m6 nut + washer + split lock washer. It took a lot of time to remove the old stud...but I think I got everything back on there.
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I was wondering, for the choke cable, whats the purpose of the nut closest to the cable entrance? I can't remember if it's supposed to pose some resistance against the cable so that the choke lever has a little resistance as well?


While I was in there, I had a BCD fuel pump I picked up a couple of years ago I wanted to install. It seems like the current pump had no support-to-engine gasket, but they used red gasket maker? Hopefully it's not a sign somethings up. I had two washers with the new pump. I put the thicker one on the bakelite to fuel pump side. Is this correct or does it matter?
View attachment 413995
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Don't worry, that inlet fuel line is not attached yet as I need to figure out if I will route the fuel return line from the carb back to the fuel pump or just cap it at the carb. Is there any benefit to cap?
The bolt that you have indicated in one of your photos is used to secure the OUTER cable of the 'choke'cable---you back the bolt off, insert ther choke cable and then tighten the bolt to secure the cable.
Which gaskets you use with the fuel-pump spacer is VERY important---by using gaskets, you 'increase (or decrease) the thickness of the spacer' so that the fuel-pump rod extends out past the final thickness of all the gaskets and the spacer, a specific MINIMUM distance--which is 1.0mm to 1.5mm.
Regarding the 'fuel-return' on the carb, I (personally) prefer to utilise the facility---I think that by continually moving, the fuel stays cooler. I have led my return round the back if the big air hose, down to a METAL 'T' piece just ahead of the fuel-pump. I led it through a length of small-bore fuel hose for protection, and secured it in place with a couple of 'P'clips.
 
Success friends!

Did the final push today to get everything finished. A few small fuel leaks later, I got her fired up and warmed up. Turned her off, and did the usual adjustment (tighten mixture and idle screw, and then unscrew until running smooth). I had to adjust the throttle linkage screw as it was just too far and wouldn't stay running. Very very happy to have gone with the 28imb, it seems to pull much stronger even with 2 people in the car.

Managed to go for an hour drive, stop start, etc. Everything seems good. Here are my notes, hopefully as always you guys can help me resolve:
  • When shifting into 3rd or 4th, when the revs drop, it seems the engine skips a beat, almost as if it's struggling to accelerate (but not cutting out). Its a short struggle when low on revs. Not always present if shifting with higher revs
  • When downshifting, double clutching the revs don't always come immediately when I blip throttle
  • When standing near the car and accelerating by hand on the engine, sometimes I get a pops & backfire from exhaust if I rev engine hard?
  • Kind of strong exhaust smell; will be checking sparks tomorrow to see if they show any signs of running rich
  • Sometimes when releasing clutch, there's a pretty strong shudder or knock; clutch adjustment? engine/trans mounts?
  • Fuel drain bolt leaked through overnight, and now I've got some small strip of mastic sealant that's come up. Can I buy something similar to fix it?
 
Just took another look at the spark plugs and it's running rich for sure. I've dialed back the mixture screw. Would adjusting the valve clearance help with this?
 
If the valve clearances are too tight and holding the valves open, they can cause all sorts of weird engine performance. It's not an especially difficult thing to check and certainly does no harm to make sure they are within the usual range.

...But as you've just changed the carb and you've visually got rich plugs, it seems likely that the poor tuning symptoms you describe are from the carb tuning. Might be worth getting the engine really nice and warm (after a good run) before having another go at setting the idle mixture.
 
If the valve clearances are too tight and holding the valves open, they can cause all sorts of weird engine performance. It's not an especially difficult thing to check and certainly does no harm to make sure they are within the usual range.

...But as you've just changed the carb and you've visually got rich plugs, it seems likely that the poor tuning symptoms you describe are from the carb tuning. Might be worth getting the engine really nice and warm (after a good run) before having another go at setting the idle mixture.
One of the problems with modern fuel is that the engines DO run a bit rich. Goldenrust's suggestions are very sebsible, but I would also suggest that you check the timing. If you still have 'points' ignition it can be done with a test-lamp, but if you have 'electronic' ignition you will need to do it with a timing-light
 
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