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Big Ends Knockin'

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AltaKnight

AltaKnight

Jedi Knight
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I was just tuning up my carbs ( never ending saga) which are now too lean after being too rich all summer, I blipped the throttle and this knocking sound started.
Having fooled about with british cars my whole life, I instantly recognized the sound of the big ends AKA rod bearings.
Up on the ramps, drop the sump and pull a couple of caps, the shells have the telltale bronze coloured under-metal showing through. So my next weeks evenings and weekend are now pre-ordained.
No use crying /ubbthreads/images/graemlins/cryin.gif just get on with it and chalk it up to the LBC experience.
My 22 yr old daughter is laughing, she thought I was BS'ing with all the tales of the cars of my youth breaking down.
Come to think of it the younger generation (and I speak in general terms) really don't know much about keeping cars going, modern cars seem to either go, or not, no in between.
 
Thats what I like about older cars. I recognize everything under the bonnet and it doesn't take a tow and 800 bucks of black box to fix something.
 
Yeah, this just happened to the 1500 engine in my racer (which is Triumph-based engine, closely related to yours).
The previous crank was fairly new and I change the rod bearing about every 25 hours, but these things don't hold up to +6000 RPM forever!
I needed a new crank and bearings, rods honed, one new piston...etc.,etc.
My bill was close to $1000 USD when done....I feel your pain!
If nothing else, these cars keep us busy and out of trouble.
G'luck!

One of my rod bearings
conrod_brng_1500.jpg
 
"modern cars seem to either go, or not, no in between."

Thats one of the nice things about older cars is the in between. I hate new cars, cause it seems anytime something starts to go wrong with one they just shut down and don't run at all. Good luck on the bearings, thats always fun.
 
I hope you put in new mains while you are there. BTW, what brand bearing are you going to use? How many miles are on the clock?
 
Yes I figured go for the mains while I'm in there. The bearings I've bought are AE made in S.Africa so hope they're ok.
There's about 60K miles on the clock which seems kind of low for this problem, specialy when my oil pressure was reasonably good at all times.
The jornals seem fine and checked out ok when I mic'ed them.
 
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