just an update.
Surgery on Francis has started, because of the delicate nature of Francis(high miles) and Terrys' worry about the insides, I've called in an expert, "Dr Mark"(race engine builder and tuner(Qual eng reconditioner 15yrs, and mechanic)and I will be assisting(I'm only a mechanic), with Dr Mark's record for last year(average engine build last year produced 399.4 rwhp) Terry aggreed Mark the right man for the job.
I started the by removing the very dirty heart(reminded me of working old trucks....DIRTY).Engine out, no problems. Removed clutch and Flywheel(2nd clutch for francis ..still asbestos type)clutch at 40-59% worn(will be reused). mounted onto a stand and started the delicate surgery..
Carby - 2.5 mm of shaft play(not sure now how francis even ran with that size vacuum leak), will need replacement.
Inlet man. Just dirty.
Exhaust man. bottom bolts came off like they were ust put on. hot box flap 3mm of play will need to be removed and holes plugged and manifold HPC coated(black)
First complication!
removing head bolts 3 were finger tight!! 2 snapped at the head, all others undid normally. One head bolt although undone wouldn't come out of the head.
Terry started to get worried when Francis wouldn't let the head come away from the block.... Emergency procedures were bought into play (brass drift) and after 20 mins the head finally came away.
with the head off it quickly became obvious that francis had a blown head gasket no2(clean piston). inspection of head revealed blown head gasket also (just) on no4 and a badly burnt ex valve on no4.
I

Pulled down the rest of the motor.
Dr Mark bought down some of his specialist surgical equipment.
Time for a measure up.
now just bear in mind Francis has over 455000kms on this bottom end.
measured all bores
worst #4 over sized by 0.0045"
will need to be bored 0.020" unless someone can sell me some cheap new 0.010" pistons and rings
measure big ends
worst #1 0.0005" under.
will need 0.010" larger bearings
measured main bearings
all ok!!!

pics soon

Amazing how was it even running? The short block still sounds good too even after such high mileage/death march tuning. Just goes to show, if you blow one of these it's because you screwed up the build.

ABSOLUTELY!

And thats why mine is going back to bog stock!! (well.. maybe not exactly..)

Zordmaker

Great build thread, love it :)

thats amazing ,i cant believ the bottom end is so good for the kms its done !

great build ,its even got clear visors too :D

granny spec !

some pics of the engine

head bolts


head stuck


head off




#4 burnt valve

Yikes those valve seats are hammered. Many miles on them ...

top ring is a bit worn




[img
width=500]http://i971.photobucket.com/albums/ae193/SanitoraOtaku/francis/DSC_0827.jpg[/img]


how did this work??


note the broken head bolt