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I tore down the second block, and the crank looks much more promising. 

19655202150_a7cbd8ac87_b.jpg

 

I'll measure the block bores tomorrow, and should be able to get down to the makerspace to use the nice micrometers we have down there on Wednesday. The bores look worn and glazed, but are hopefully still round enough to get away with a hone.

 

There was some funky noise coming out of the t5, and I think I discovered where that was coming from as well as finding out why an input shaft wasn't included.

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Thankfully, the gear faces look decent, and the bearings that exist don't sound crunchy at all. I'll have to take a better look at the syncros to make sure they're serviceable, but this isn't nearly as terrifying as I expected my first transmission teardown to be.

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If you want I'll print you up a spacer in ABS.  No big deal.  Just Email me the dimensions.  ABS would easily handle any heat in that area. I'd even include the tech drawings and .stl since it looks r

I'm no machinist ... but apparently this t5 is. These are the big chunks I pulled out of it, and a quick run with a magnet pulled out a few ounces of ferrous sludge from the bottom.

19904017061_10784bf072_b.jpg

 

There's one chunk still in there, but I may just drop the whole thing off at a transmission shop if the price is reasonable. Have them disassemble it, replace the syncros, and while it's apart that piece should just fall out on its own.

19712356459_acd95ed7ce_b.jpg

Edited by Jesse OBrien
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There's more to good transmission operation than just synchros.  The teeth on the gear itself, for example.  The teeth on the coupling sleeve.  They're on the inside.  Proper alignment of the shafts.  Proper alignment of the gears.  Shift fork wear. 

 

Synchro replacement makes slightly worn transmissions work like new if you get there in time.  You are way late.  The odds are against you.

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None of what you see came from any of the internals of the transmission. The gears are untouched, and the synchros are all still there. By "replace the synchros", I mean "rebuild the transmission". I don't know of any transmission shop that would JUST replace synchros ... and wouldn't take any business there anyway. A Ford t5 rebuild kit goes for around $250 in parts. A well rebuilt trans is worth around $1k to me, and labor appears to be pretty straightforward if you've been through this dance a few times before.

 

There's no knife edging, chipping, or cracks on any of the (visible) transmission gears. Aside from the one chunk of input shaft that's between the two gears in that second photo, the only damaged component appears to have been the input shaft.

 

Correct me if I'm wrong on any of this, I'm perfectly happy to listen to the voice of experience.

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 Aside from the one chunk of input shaft that's between the two gears in that second photo, the only damaged component appears to have been the input shaft.

When things jam and break and the broken pieces then jam between other parts, damage can be subtle and hard to see.  Looks like you'll need more than just a $250 rebuild kit by the time you're done.

 

Good luck.  I'm interested in how much it ends up costing and how well it works when it's done.  I'm no expert.  It just seems like you could find  a working used transmission and get it rebuilt, and be ahead when it's over.  Yours look like it needs to be repaired by an experienced professional.  I wouldn't take it a shop that will just install the parts from a rebuild kit.

 

Start a thread on rebuilding T5's, with those pictures, and you might get some good input.

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Finally, some good news. I measured the bores on the block with a good-looking crank. The worst out-of-round on block #1 is .00175", tolerance is .005". The worst taper difference is .00150", where tolerance is .010". The worst bore tolerance overall is .002", where tolerance is .04". With modest power goals (250ft/lbs is enough to make me happy), this block looks really promising.

 

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I still need to get down to the makerspace to measure the crank journals, and I'm definitely looking for advice on DIY magnetic particle inspection (magnaflux). I have access to ridiculously powerful magnets, I just don't know what kind of media to use yet.

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  • 4 weeks later...

Despite everything looking promising, I just went over my 2016 budget, and it doesn't look like the 302 is going to happen. It's just too expensive to get all the little do-dads together to have the engine running. Even if I were to just run the Miata next season, I'm looking at a little over $8k for the season budget. Without sponsors helping me out, that's a tough pill to swallow.

 

 

The Full Budget is viewable by everyone. Be sure to look through the available tabs to see a more detailed breakdown.

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  • 1 month later...
I spent some time nerding out on the hillclimb classification sheet, and can't come up with a way for the 302 to be viable in the street prepared class I'd like to be in. It's pretty light already, and the only class I could get into on street tires is sp2 (I'm not a good enough driver to survive there yet). I'd much prefer sp4 or sp5, which seems to be more inline with where my driving skills are right now anyway. As a result, the 302's are up for sale (along with the two world class t5's), and I just started down a different path. The l28et is probably going to stay in the engine bay for 2016, just so I don't overwhelm myself, but right now this is what's on my bench.

 

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It might be a mistake, I haven't inspected any components, but I can't visually identify any problems with it. I'm going to have to do some reading to figure out what to measure and see if it's usable. Luckily, all the expensive stuff (and all the accessories) are included, and I already have the car wired for Megasquirt. I'll need injectors ... or I can finally put these to use.

 

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There is certainly documentation on this sort of build, so I have a bit of reading to do before I'm ready to do anything, but the project has changed directions one more time. Hopefully I'll have this engine in and reasonably well-tuned for 2017 (Pike's Peak and Climb to the Clouds, perhaps).

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  • 1 month later...

Because the project has changed so drastically, I started a new build thread. Please follow it over here:

http://forums.hybridz.org/topic/123780-driven-daily-hillclimb-2016-build/

 

As for rotaries, Aux takes the cake for having the most details laid out.

http://forums.hybridz.org/topic/49371-so-you-want-to-swap-a-rotary-into-your-z-how-to/

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