
340 rebuild, help / recomendations
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340 rebuild, help / recomendations
I recently bought a 340 engine to upgrade my 318 powered B body, I was hoping to clean it up and install it.......but with the sump off I can feel a bit of play on a couple of the big ends, oh joy....I dont really have the confidence to take on this job by myself, so the best I can hope for is to find someone local ish to undertake a rebuild, I live in north Essex....any help or recommendations would be greatly appreciated.... 

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- Joined: Fri Nov 04, 05 8:40 pm
- Location: Cornwall
I have just rebuilt my 340 stroker there might be some help on my thread
http://www.moparuk.com/forums/viewtopic.php?t=47147
http://www.moparuk.com/forums/viewtopic.php?t=47147
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- shovelheadrob
- Posts: 959
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First work out your budget, then your goals, if the 2 are compatible pull the motor apart & measure & inspect everything before buying a load of performance parts. Stripping & rebuilding is easy enough as long as you take your time & are meticulous about it, there are plenty of people here who can advise & possibly assist if needed, for what you want the 340 would be better than going BB, but you might have to upgrade your trans.
You can't have too much power, only a lack of traction!
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- Posts: 7309
- Joined: Fri Nov 04, 05 8:40 pm
- Location: Cornwall
i'd put the sump on
fill it with diesel or paraffin
Bananarama! all out
turn it over
sump off
I'd do the big end bearings checking for scoring, if none get on with it
undo big end
loop a nylon chord round the rod
tap the studs till the cap pops off
make two little stud covers from making tape or rubber tube
knock the rod down the bore a little way
move crank round
retrieve other bearing half
new bearing in
assembly lube
top half in cap
yank piston/rod back up or pull up by hand depends totally on ring tension
wind crank slowly round and guide rod onto it
cap goes on so that cap number sits next to rod number
just buy the same part number as on the back of the ones you take out
clean it
sump on
prime it with new clean oil
and run it.
I did many years of happy daily driving this way as a teenager/student
any top end issue makes itself known within 50 miles (smoke/steam/smoke and steam) if you didn't see it run or compression test
and you can do everything top end with it in the car apart from rings and hone unless you are very unlucky
you can even have a positive effect by putting in just a new cap half of the mains (easier to do if you have a pile of cast-off bits and remnants from previous disasters....
most of us will have a half used set of bearings in a box somewhere, none of us should but I'm willing to bet most do )
its the wrong way to do things but 90% of the time works satisfactorily
we all take many things to bits and rebuild for no good reason other than knowing.
Dave
fill it with diesel or paraffin
Bananarama! all out
turn it over
sump off
I'd do the big end bearings checking for scoring, if none get on with it

undo big end
loop a nylon chord round the rod
tap the studs till the cap pops off
make two little stud covers from making tape or rubber tube
knock the rod down the bore a little way
move crank round
retrieve other bearing half
new bearing in
assembly lube
top half in cap
yank piston/rod back up or pull up by hand depends totally on ring tension
wind crank slowly round and guide rod onto it
cap goes on so that cap number sits next to rod number
just buy the same part number as on the back of the ones you take out
clean it
sump on
prime it with new clean oil
and run it.
I did many years of happy daily driving this way as a teenager/student
any top end issue makes itself known within 50 miles (smoke/steam/smoke and steam) if you didn't see it run or compression test
and you can do everything top end with it in the car apart from rings and hone unless you are very unlucky
you can even have a positive effect by putting in just a new cap half of the mains (easier to do if you have a pile of cast-off bits and remnants from previous disasters....

its the wrong way to do things but 90% of the time works satisfactorily
we all take many things to bits and rebuild for no good reason other than knowing.
Dave
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