crankshaft bearings.

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Chris_1
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Sat Apr 09, 2005 10:57 am

Can you remove the bearings with the crank shaft in situe?
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Sat Apr 09, 2005 1:05 pm

Chris wrote:Can you remove the bearings with the crank shaft in situe?
No, if you have the engine upside down, the crank sits on the bearings so needs to be removed to change them. Are you having trouble with the large bolt in the front of the crank?
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Chris_1
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Mon Apr 11, 2005 8:47 pm

Have not even started yet. Was dead set on getting rid of car and now a friend is trying to get me to take it apart. Don't even know if it is big end bearings but that seems to be the general consensus!
Andy_magic
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Mon Apr 11, 2005 9:46 pm

Big end bearings can be done, but if it's knocked a set of bearing out the crank will not be true and will need grinding to do it properly.

There is a bodge it method for changing main bearing with the crank in but you run a risk if ruining the shells, crank and block.

You need something that will fit into the oilway of the crankshaft and push against the end of the shell bearing. It also needs to be slightly thinner than the shell bearing your fitting, you then turn the crank and the ground down bolt pushes the old shell out, you reverse this process to refit the new bearing. But it is a total bodge and I really don't recommend it.

The best way is a complete motor rebuild, but this costs more than sourcing a decent motor to just drop in.
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Mon Apr 11, 2005 10:02 pm

A bottom end rebuild with me doing all the disassembly and refitting was less than Ԛ£300 for my 325i.

The cheapest 2nd hand engine with a reasonable guarantee was about Ԛ£400 and that obviously had a fair few miles on it.

A top end rebuild with new guides was around Ԛ£200 and all the gaskets etc. for the whole engine came to another Ԛ£210 so that's Ԛ£710 for a pretty much brand new engine.

That didn't include pistons though as mine were luckily fine :)
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Chris_1
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Wed Apr 20, 2005 6:59 pm

Cheers for the advice lads. Don't feel like spending 700+ on it, will have a look and see if it is big end this weekend.
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