Fiesta poor downshift to 1st

[borgward]

Are there any special tools I need to disassemble the mainshaft assembly to get to the 1st gear synchro? I suspect there may be a spring loaded ball bearing that is part of that 1st gear synchro assembly and that is what is causing 1st gear to pop out of gear sometimes. It would pop out with a bang until I developed a sense of when it would happen and just take off in 2nd.

I would not be surprised if the synchro rings did not show much wear. I could shift into 1st at a crawl with no grinding.

 

[borgward]

There have been some videos, and I remember coming across a blog about how someone took apart and B5 earlier version and found out how the end caps retained the bearings - so your issue with the OEM transmission may fit this profile especially if the larger shifter lever in the front cover box on the tranny is the larger wedge shape and it's pivot point was nothing more than a smooth stud and the bushing on the lever was all it had to cushion and move against this metal stud.

Here's an example...

View attachment 10077​

What I'm trying to help here with is to establish a build date or year so you can see how the iB5 evolved into what it is now. Many of the older mechanical ways of making this work were built on the smoothness of the shifter and overcoming some obstacles of needed redundancy - as in the shift forks work the ring gear onto a cone that then forces another gear to move as the syncro presses teeth into the splines and it slides onto the gear as a single unit once all the teeth are meshed and aligned so the fork slides it over onto the gear next to it.

Because? The newer gears and their support are not always backwards compatible with the older rebuild or case designs.

I get what you're telling me. That piece in the picture moves smoothly. No slop. All those external linkage parts move nicely.

I took the transmission apart. Very clean. Very little filings on the magnet. Just about no wear on the parts. Bearings feel good. I noticed that when I moved the 1st/2nd synchro assy back and forth that one of those 3 rectangular pieces (dogs?) did not always move along with the other 2.

I took apart the main shaft assy. I then took apart the 1st/2nd synchro assy. See picture. Those 3 pieces reside inside the synchro hub and are held in place by a semicircular spring on either side. I don't know how to assess how good those springs are.

I had a lot of fun getting the 3 circlips off of the main shaft. Is there a source for new ones?

 

[Handy Andy]

Try this FoMoCo String...
FoMoCo 7s6r-7c115-aa

In your search engine, you'll come up with the 1-2 syncro - but to find a rebuild kit? Not sure...I get some hits but you'll need to take it from here...

So you know, the teeth do show some considerable wear on the face - and the brass of the syncro gearing took most of the beating and since it was soft, shows the blunting of their edges - so the tranny needs some service but not sure what kind of wear abuse this was - if it came straight from the factory this way or did someone get cute with it and used a far thinner fluid like Dextron LV? Light loads it's - not a bad idea but this is a manual and uses the gearset to move oil to press into the surfaces.

 

[borgward]

Try this FoMoCo String...
FoMoCo 7s6r-7c115-aa

In your search engine, you'll come up with the 1-2 syncro - but to find a rebuild kit? Not sure...I get some hits but you'll need to take it from here...

So you know, the teeth do show some considerable wear on the face - and the brass of the syncro gearing took most of the beating and since it was soft, shows the blunting of their edges - so the tranny needs some service but not sure what kind of wear abuse this was - if it came straight from the factory this way or did someone get cute with it and used a far thinner fluid like Dextron LV? Light loads it's - not a bad idea but this is a manual and uses the gearset to move oil to press into the surfaces.

Ford claims there is not a rebuild kit. I don't think there is considerable wear. If there was, where's the filings? Just a tiny amount on the magnet. Would be nice to see a picture of new gears for comparison. The fluid was what ever was put in it at the factory when I bought it new. I am considering buying the 1st/2nd synchro unit as I can't figure out why it would intermittently pop out of 1st on take off. If it stayed in 1st I could apply full throttle and it would stay in gear. I suspect it has something to do with those 3 things in the synchro's hub that are held in by those 2 springs. I did notice that one of them would sometimes not move the same as the others. Maybe something to do with that those springs. I would try moving the shifter back and forth several times and then 1st would hold.

Ordered the synchro unit from a Ford dealer. It is an updated one for my car. I am now on the hunt for the 3 circlips ford P/N E860141S (HR2), E860146S (HR3), and E860303S100 (HR4). forget ford terminology for them.