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Discussion Starter #1
My engine builder has asked that I clean the block internally but I have some difficulty as the crankshaft has been left in situ (He says that the front pulley nut is very difficult to remove) and I am terrified that debris may go undetected. Is it safe to try and clean the block with the crank in situ? I have masked the crank holes but the two main bearings at the front and rear run very tightly in the block and I wonder if there is a risk to mask these holes. In any case, should not all the holes also be washed out?

I do not have compressed air available. Do I need to buy a compressor?
 

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I would not clean a block with the crank in place. Water will get trapped in the bearings.
And yes, it is good custom to blow out water from everywhere with compressed air, following the wash.
 

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Discussion Starter #3
I would not clean a block with the crank in place. Water will get trapped in the bearings.
And yes, it is good custom to blow out water from everywhere with compressed air, following the wash.
This was my fear. I take it that the front pulley nut is not such a major issue but I suppose it could be?
 

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I’d be concerned about an engine builder that even suggested it...

... and surely an engine builder would have the equipment to clean parts prior to assembly.
 

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I'd agree with that. Nothing hard about removing the crankshaft pulley other than forgetting it is left hand thread. If an impact wrench won't remove it, apply heat to the pulley bolt.
What's an extra pulley bolt in a rebuild?

As the block is in situ, there has been no machining of the block. Therefore the chances of debris are reduced but a footpump with attachment of a football should be enough to clear any light particles from oilways. I'd still allow the crankshaft to droop or have main bearing shells out (refit caps loosely though) when blowing air through.

Any spirit cleaner should work right the way through to diesel. The cleaning agent shouldn't be that important as long as the oilways were clear originally.

It's nice to have everything absolutely pristine for reassembly but as long as there is no major foreign debris, there should be no issues.
 

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Discussion Starter #6
I'd agree with that. Nothing hard about removing the crankshaft pulley other than forgetting it is left hand thread. If an impact wrench won't remove it, apply heat to the pulley bolt.
What's an extra pulley bolt in a rebuild?

As the block is in situ, there has been no machining of the block. Therefore the chances of debris are reduced but a footpump with attachment of a football should be enough to clear any light particles from oilways. I'd still allow the crankshaft to droop or have main bearing shells out (refit caps loosely though) when blowing air through.

Any spirit cleaner should work right the way through to diesel. The cleaning agent shouldn't be that important as long as the oilways were clear originally.

It's nice to have everything absolutely pristine for reassembly but as long as there is no major foreign debris, there should be no issues.
Thank you for all the replies.

The complication of the rebuild arose because I wanted to use a spare 50K engine that I had stored in my garage. It seemed logical at the time to recover my Sportpack and swap engines in my garage. Having consulted here first, I had the bottom end checked...lo and behold,....the big ends on the 50K engine needed replacing........so I am resigned to doing all the preparation work for the rebuild at home. I haven't any experience of this and am worried that I might not be able to do a thorough job without sufficient knowledge. Ultimately, if it is possible to successfully clean the block with crank in situ I would prefer it. How best to clean the crank oil-ways and do I need to use a pressure washer? Should I invest in an air compressor?
 

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You won't clean it properly with the crank in place. At all. Anyone who suggests you can should not be building your engine.

If your engine builder can't remove the crank pulley, get it to a machine shop who can.

If the big ends needed replacement, the mains are highly likely to be damaged as well.
 

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What this shows is you can get different answers.
What I suggested is possible but rxe and brinker both rightly think it is not desirable. They are right. It is not a desirable course of action.

To get the best answer, what state is block in, where is it, what has been done to it and what is going to be done to it?

As you have not done tho sort of thing before, it certainly makes sense to do it textbook style rather than having to be creative. There are less chances for things to go wrong.
 

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What this shows is you can get different answers.
What I suggested is possible but rxe and brinker both rightly think it is not desirable. They are right. It is not a desirable course of action.

To get the best answer, what state is block in, where is it, what has been done to it and what is going to be done to it?

As you have not done tho sort of thing before, it certainly makes sense to do it textbook style rather than having to be creative. There are less chances for things to go wrong.
Agreed.

You could try and clean it by (?) pressurising the oil intake with cleaning fluid. This is hard, you need a pump with cleaning fluid, and an ability to block oil galleries. You also run the considerable risk of whatever crud caused your big ends to fail fouling the mains or a gallery elsewhere. I think the chance of the mains being in perfect order with the big ends shot is slim.

I really don't get the problem with the pulley - with the sump off, locking the engine with timber is easy, and it's just a question of getting an impact gun onto it.

I've got a well equipped garage and have built several engines - I would not even think of attempting this .
 

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Discussion Starter #10
Agreed.

You could try and clean it by (?) pressurising the oil intake with cleaning fluid. This is hard, you need a pump with cleaning fluid, and an ability to block oil galleries. You also run the considerable risk of whatever crud caused your big ends to fail fouling the mains or a gallery elsewhere. I think the chance of the mains being in perfect order with the big ends shot is slim.

I really don't get the problem with the pulley - with the sump off, locking the engine with timber is easy, and it's just a question of getting an impact gun onto it.

I've got a well equipped garage and have built several engines - I would not even think of attempting this .
Thank you all. The block is completely stripped and separated from head, sump pistons & rods. Turned onto its bore side to allow the cleaner to flush into a collector below. The crank is in position but the journals are masked. The caps on the ends are in place and the bolts nipped-up. The oil feed is also masked.

I am pondering on removing from the front of the engine, the engine pulley cap and the P/S support bracket and half-shaft but am worried that the gasket for the former might have been discontinued?
 

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The block is completely stripped and separated from head, sump pistons & rods. Turned onto its bore side to allow the cleaner to flush into a collector below. The crank is in position but the journals are masked. The caps on the ends are in place and the bolts nipped-up. The oil feed is also masked.
:titanic:
 

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Seriously, get the pulley off.

Step 1 - put a bit of 4x2 in a crank web and either get an impact gun on it, or swing on it with a big socket.
Step 2 - as step 1, but with heat. Preferably an oxy-propane plumbers torch. A mighty oxy-acetylene blowtorch is even better.
Step 3 - drill the nut, and then split it with a chisel. This will definitely work.

Without getting the pulley off, you can’t change the mains, you can’t clean the mains, you can’t replace the crank front oil seal and I suspect you may have fun getting a cambelt on.
 

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Discussion Starter #13
Seriously, get the pulley off.

Step 1 - put a bit of 4x2 in a crank web and either get an impact gun on it, or swing on it with a big socket.
Step 2 - as step 1, but with heat. Preferably an oxy-propane plumbers torch. A mighty oxy-acetylene blowtorch is even better.
Step 3 - drill the nut, and then split it with a chisel. This will definitely work.

Without getting the pulley off, you can’t change the mains, you can’t clean the mains, you can’t replace the crank front oil seal and I suspect you may have fun getting a cambelt on.
I followed the steps 1) and 2) but they failed so I tried a local machine shop but the bolt chewed off their socket and so I tried Alfaworkshop and Jamie confirmed step 3) as being the only solution....now armed with a new crank bolt could anyone suggest how I might apply the prerequisite 340-378 NM on a left hand thread?!
 

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could anyone suggest how I might apply the prerequisite 340-378 NM on a left hand thread?!
One of my torque wrenches looks much like the one on the following page:

https://www.ebay.com.au/itm/Pointer-Socket-Torque-Wrench-300N-M-Dial-Torque-Spanner-Auto-Repair-Tension-Z8M7/283565643199?epid=17031648188&hash=item4205d455bf:g:voUAAOSwnkNdQQYN

As will be obvious from the photo it will measure torque with both left and right hand threads, but it only goes to 300nm. I've not ever had to tighten a left handed bolt to such a high torque, but what I would do in your situation is to torque to the max the torque wrench can measure, and then using a long handled 'breaker bar' of more or less similar length to the torque wrench, tighten the bolt a bit more. Others may blanch and disagree...

I'd also use an 'anti seize' compound on the (cleaned) threads, and under the bolt head.

Regards,
John.
 

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Impact gun, electric or air turned up to max.

300 NM is “VFT”, doesn’t need to be measured precisely.
 

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Left hand thread means it will tend to tighten in service anyway.

John figures other may criticise his method but I think I can hold my hand up and say I've probably greatly under-tightened quite a few.
I'm happy to say not a single one has come off, slackened' allowed movement and caused wear or produced strange noises.

Maybe it's just as well these electric impact wrenches are getting ever cheaper and better. I should get one of the Milwaukee Fuel brushless ones. I think they are the best right now even if the De Walt batteries seem to be the most reliable.
 

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I tend to agree that for crank bolts the specific torque value doesn't matter a great deal, so long as it's very bloody tight. I mean this to apply only to the pulley bolt, it does matter quite a lot with any other bolt associated with the crankshaft.

IMO pulley bolts are generally so big that it would be quite difficult to overtighten the bolt to the point of causing an issue, unless you were unusually strong or used a very long lever. Same for driveshaft / hub nuts, IMO.

Over the years I've come across quite a few pulley nuts (and driveshaft nuts) that were exteremely difficult to undo, the torque needed being far in excess of the specified tightening torque. This isn't because they had been previously overtightened, but due to oxidation of the threads and under the bolt head creating a great deal of 'stiction' (and one of the reasons why an anti seize compound is a good idea, other than lubricating the thread and head underside during tightening). I've also come across a few which were frighteningly easy to undo...

Not useful for you in this case, but 'cracking' the bolt free would probably have been fairly easy if it were a right hand thread. Our Saab 95 had a very tight crank bolt, I just couldn't shift it no matter what I tried, until I came across the 'starter motor method'. This involves disabling the ignition (important!), placing a socket and breaker bar on the bolt head, supporting the end of the bar on an immovable object (in this case a large block of wood placed on the ground, mostly to optimise leverage angle of the bar), then momentarily turning the motor over with the starter motor. This applies a huge torque to the pulley bolt, and unless it is virtually 'welded' on with rust, should 'crack' it free.

Worked for the Saab, but it WON'T work with the TS due to the left hand thread (you'd just be overtightening it more...).

Regards,
John.
 

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Discussion Starter #18
I tend to agree that for crank bolts the specific torque value doesn't matter a great deal, so long as it's very bloody tight. I mean this to apply only to the pulley bolt, it does matter quite a lot with any other bolt associated with the crankshaft.

IMO pulley bolts are generally so big that it would be quite difficult to overtighten the bolt to the point of causing an issue, unless you were unusually strong or used a very long lever. Same for driveshaft / hub nuts, IMO.

Over the years I've come across quite a few pulley nuts (and driveshaft nuts) that were exteremely difficult to undo, the torque needed being far in excess of the specified tightening torque. This isn't because they had been previously overtightened, but due to oxidation of the threads and under the bolt head creating a great deal of 'stiction' (and one of the reasons why an anti seize compound is a good idea, other than lubricating the thread and head underside during tightening). I've also come across a few which were frighteningly easy to undo...

Not useful for you in this case, but 'cracking' the bolt free would probably have been fairly easy if it were a right hand thread. Our Saab 95 had a very tight crank bolt, I just couldn't shift it no matter what I tried, until I came across the 'starter motor method'. This involves disabling the ignition (important!), placing a socket and breaker bar on the bolt head, supporting the end of the bar on an immovable object (in this case a large block of wood placed on the ground, mostly to optimise leverage angle of the bar), then momentarily turning the motor over with the starter motor. This applies a huge torque to the pulley bolt, and unless it is virtually 'welded' on with rust, should 'crack' it free.

Worked for the Saab, but it WON'T work with the TS due to the left hand thread (you'd just be overtightening it more...).

Regards,
John.
Thank you all for the encouragement and detailed information. I have ordered a 980 Nm torque wrench but I'm pretty sure that I must need also a socket that would be up to the job! Any recommendations please?
 

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Discussion Starter #19
Could anyone recommend a crack testing shop...........I just dropped my crankshaft that had only completed 50k..............
 

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Depends where you are. Knowing that would certainly help. When I replaced the crankshaft in my 33 I had it crack tested at Baldynes on Biigin Hill aerodrome.
 
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