Topic: Pumpkin Pie

[The Gurg]

So I’m about to reassemble my dismantled ‘75 cb750 engine, my first rebuild, and had a question.

Years ago, I was making a pumpkin pie from fresh pumpkin. Only slightly less masculine than rebuilding an old engine and doesn’t require a good torque wrench. The directions assumed you knew to boil the pumpkin before using the raw pumpkin. They assumed any amateur baker knew this. Not only does raw pumpkin taste pretty strange, it’ll give you diarrhea...so there’s that.

I’m using Mark Paris’s book, the shop manual and two different YouTube channels as sources. My question is what are the things assumed when giving instructions in rebuilding an old engine that an novice might not know. What’s the “oh yeah, you’ll need to boil the pumpkin” of rebuilding this engine.

[Don R]

 Good point. Maybe which surfaces get case sealer and where to not put it? As in, don't get it where it will squish into the bearings.  I also use an inch pound torque wrench when possible because I feel they are more accurate on smaller bolts.

[robvangulik]

Maybe the fact that all nuts, bolts and threads on these Honda's are metric?
And all crossheads are NOT Phillips, but Japanese Industrial Standard, so JIS ?

[jaytee-nz]

Manuals often state "re-assemble in the reverse order" but before you do that check that all internal threads in the crankcases etc are good before you start reassembly. The PO will have no doubt over tightened at least one bolt resulting in stripped threads.

[flybox1]

sealant surfaces for the case halves took a while to figure out.  as far as the sealant goes, less is better.
I applied mine with a toothpick to minimize the excess bead on the inside...which leads to less material to come loose to clog oil jets.

two torque wrenches.  one small and one large.

assembly lube everything.

[ekpent]

 Plug open holes and cavities when working so you don't drop bolts,screws or circle clips down inside the engine. Cam tower bolt threads in the head can be fragile,don't strip them out. Put thread lock on cam sprocket bolts. Lots of fun stuff !

[pjlogue]

Patience and lots of it.  Take pictures before and during disassembly.  You mat think you can remember where things go but after a couple of weeks you will forget.  Make notes as well.  Keep your work area clean. 

A lot of bikes have been buggered up by previous owners taking short cuts or not using the proper tools.  If you come across a real problem take a brake and give thought to the best way to solve it. 

-P.

[low-side]

I like everything everyone has said here.  FWIW, I am considering preemptively heli-coiling the 6mm holes in the cylinder block and cylinder head on the next CB750 engine I build.  There's nothing like almost completing a stage of engine assembly and having to start over after stripping a set of 6mm threads (and risk contamination from having to fix the stripped thread).

[bryanj]

Carefull with those holes as if you convert blind holes to through holes oil can "wick" down the thread. Also Keenserts are a stronger option.

[turkey4me]

Start a build thread on this forum to post your progress.  If you do this, then we'll let you know when you forget to pre-cook your pumpkin. I never did and still have diarrhea.

[johans]

If you paint the engine cases while apart , make sure you get no overspray on the inside and especially the two inner studs that serve as an oil galleyway for the cam. The unfiltered hot oil can reactivate the paint and clog the oilway and destroy your cam.

[The Gurg]

All of these are so great! Really helpful stuff!

[MauiK3]

Paint after cases are together, use lots of blue tape.

No fluids in blind holes, it will break the casing.

Mark Paris' book has the information on where sealant goes.

Lay all the case bolts out in advance, I drew the outline of the upper and lower case on cardboard pieces, made holes where the bolts go and put the bolts in the holes, that way there is no searching for the right bolt as sealant is drying.

I "dry assembled" my cases once just to get the feel for how long it took to get the case down with the shift forks lined up.

When you are done torquing them all up, run the wrench around again to double check.

Best of luck

[flybox1]

acetone and kerosene are great parts cleaners
Acetone for dry parts, kerosene for wet (oiled) parts.
dont use these together.
do use rubber gloves.