1970 s2 0453R Reassembly

[dakazman]

  While inspecting the bearings on the 843 motor I Found that most bearings surfaces were allmost perfect . One had a gouge in it and created a hot spot right into the caps. I further inspection I saw some scratches on the lower cylinder sleeves. I removed the pistons and found no markings as to positioning in the motor. Pulling number 2 piston , connecting rod wrist pin was extremely tight , severely melted piston over the rings. I don’t know why this would have happened to what seems to be an engine that was previously just reassembled .  I guess I have another delay! 
    My order for my under dash A/C system came in and all in good condition. Now to start on placement. 
    Seats , who would guess sewing thread would be out of stock here in the US, Canada to the rescue even with once a week crossings vendor shipped my order a week later.
    Header tubing and collectors came in . I fabricated a 3/8” steel plate head exhaust plate , cut and drilled holes. Watching a few you tube videos on weather to buy a MIG or TIG welder . Reading of intake and exhaust systems moving along slowly, but found a few more ideas. Still looking for that modeler BDA, I’ll get a file somewhere but I need more uninterrupted time.

 Dakazman

[GavinT]

Excellent result, D'man.

I think it's safe to say that piston is stuffed . . even with the 'economical' 320x240 pics.
This is the outcome you needed to forge ahead (geddit) with some higher compression pistons.

What was the story behind "previously just reassembled"?

[jbcollier]

I have rebuilt many, many just rebuilt engines.  Unless it comes with receipts from a shop known for its high quality work, always budget for a complete strip to check it over.

[dakazman]

  Gavin, the engine had signs of usage , old caked on ,burnt oil . The main bearing surfaces look brand new and the connecting rods barely worn in.  I purchased two engines from California way back for parts , well this was one.
  JB, exactly why I opened it up. It doesn’t add up that this much damage is on one piston and yet the engine turns over so easy.  I also found alot of sandy grit In all the bolt cavities.
  Well some high compression pistons and larger valves Are now in its future and other upgrades you guys mentioned, except for milling of the head . I’ll post better pics soon.
 
   Since I have choices for my build:
1. The original Without A/C
2. An 821 with new liners and pistons (stock)  with the crankshaft from the 843 , for the A/C. Talking to delta cams on two regrind on the cams (2).
3. Just build the 843 new pistons (high comp) screamer!😃 with A/C

Gaining experience fast but it should be worth it in the end.
Dakazman

[Pfreen]

Go for the screamer!

[dakazman]

Lol, yep it’s fate, glad I caught it before I had a nice big hole in something and the body on.
I’ll probably go find another machine shop also so I can be done this year.
Dakazman

[dakazman]

    Fast questions.pertaining to a crossflow, Can the liners be bored over to accept larger pistons? I remember reading max piston size is 82mm. Who is a good supplier of forged pistons here in the states or canada. Connecting rods?
dakazman

[GavinT]

Yes, the liners can be bored out but it can be tricky.
Allegedly there are bike shops that do this regularly so they may be more experienced.

But why not just get a whole new piston/liner set?
That's kinda the way the engine was intended to be refurbished.

Lots of suppliers from Mecaparts to Salv Sacco and many others - not sure about NA.

[dakazman]

Offline Valerio Leone
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wedge engine 821/697 the ultimate evolution.
« on: Saturday,July 18, 2015, 06:46:39 AM »
Quote
Lightened crankshaft (-1.5 kilos)
Lightened rods (by saenz) and pistons (-120 grams each)
Aluminium flywheel by fidanza (-3.5 kilos)
Pistons CPS italy CR 11.5/1
cam 43-73-67-37 lift 108

 Gavin,  I’m new to building a Custom engine. the above build (for a wedge)  mentioned 11.5/1 pistons , yes To high for what I want but a street able 10.5 piston. I went with to that website to see what was available. Wow, a lot of choices ,? ... I saw the kits at Meccaparts and probably the better route for a novice like me .
 
   On another note, I did find a cam shop that will regrind my 821 cams . I will have one cam cut stock and the other a slightly aggressive version. They also stated the hey have cores and they can make anything. I just received my chemise kit for my 2nd 821. My only holdup will be finding another 843 crankshaft with the pulley assembly and the timing chain cover. I want A/C  in Florida in a black car. 🤪
 

Dakazman

[dakazman]

    While waiting for some parts decided to clean and polish some items up to my normal standards.
This block was extremely corroded and still only sanded to 220 . 
Dakazman

[TurboFource]

 

[BDA]

D'man, make sure you get some good sunglasses when you get your car going!

[1970EuropaGuy]

Looking great as usual. I'm sure it's been asked and answered in the previous 72 pages, are you coating the aluminum and what with if you are?

[dakazman]

  70’ Yes , I’m using a hi heat ceramic clear coat. I’ve seen the effects on the paint on the Classic Honda motorcycle I’ve polished a year ago . Without coating water spots were killing me. Afterward, finish remained bright and mirror like.
   It is a lot of work, first engine took about 24 hours of sanding and polishing. This one badly corroded pits etc has taken 40 and still needs about 16 more. The next one, an 821 is in great shape and will only take 16 hours. 
   I don’t sit there in large blocks of time but as a filler between jobs.
Dakazman

[1970EuropaGuy]

You have me motivated to polish mine. Perhaps I'll pull it next winter and polish it up. I love polished aluminum!