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BMC 1.5 Crankshaft Bolt


MrC

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28 minutes ago, Mad Harold said:

I posted this qustion not long ago,and although I didn't remove the nut(I sold the boat) the answer from one of CWF members,was to wedge a tyre lever or similar piece of metal in the starter ring.

Exactly that, I used to have a large blade screwdriver just for that sort of job. Put it in the starter ring gear, turn the crank anti clockwise, as seen from the front, until the flywheel is jammed, then socket on the bolt head. Then a big tommy bar, and give it a sharp tap with a hammer. It saves having to lean on the bar in a confined area. Other methods are also available.

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4 hours ago, Gilsteamin said:

Thank you. I’ve also located the pulley wrench so I can hold it in place. Just got to acquire it now. Thank you again. 

I’ll grab my large tyre levers as well just in case. Many thanks guys. ???

Not sure what the pulley wrench will fit onto if its to hold the pulley while you  loosen the bolt but on no account try to  hold the outer portion. It is fixed to the inner part with the bolt in it by  a rubber ring and if you damage the rubber you need  anew pulley or risk a snapped crankshaft.

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On 25/02/2020 at 15:37, Gilsteamin said:

Hi Guys. On this subject, how do you remove the nut? The manual mentions the tool but it’s not illustrated in the manual tools section. Need to stop the pulley moving so it can be removed. ??‍♂️

 

I found it easy. Forget to remove the spanner after adjusting the tappets and try to start the engine. Next job was to repair the pipework to the calorifier.

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The quick and unsafe way (  Professional? )  is to fit a ring spanner, free end over the port engine bed, and hit the start button with the stop button held in the stop position. 

Not recommended, do not try this unless you are very experienced in machinery and keeping yourself safe.

 

Under no circumstances grip the outer edge of a BMC 1.8D crankshaft pulley as Tony warned, else you will definitely  wreck the bonded rubber in the pulley and they are expensive. The  BMC 1.5D has no rubber.

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16 minutes ago, Tracy D'arth said:

The quick and unsafe way (  Professional? )  is to fit a ring spanner, free end over the port engine bed, and hit the start button with the stop button held in the stop position. 

Not recommended, do not try this unless you are very experienced in machinery and keeping yourself safe.

 

Under no circumstances grip the outer edge of a BMC 1.8D crankshaft pulley as Tony warned, else you will definitely  wreck the bonded rubber in the pulley and they are expensive. The  BMC 1.5D has no rubber.

All those on the hire fleet did and its why one boat got to Cookham and snapped the crankshaft. Unbeknown to me a young engineer had for some reason put the pulley into the degrease bath and left it there for several days. Upon removal he found the rubber damper had swollen up so he just cut the surplus off and fitted the pulley.

 

So I believe that the 1.5s do have the rubber insert but the pulley will look rather different. It still has a flywheel outer and a   rubber insert.

 

I agree I would use the method above to free the pulley but I would use a socket and breaker/knuckle bar.

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3 minutes ago, Tony Brooks said:

All those on the hire fleet did and its why one boat got to Cookham and snapped the crankshaft. Unbeknown to me a young engineer had for some reason put the pulley into the degrease bath and left it there for several days. Upon removal he found the rubber damper had swollen up so he just cut the surplus off and fitted the pulley.

 

So I believe that the 1.5s do have the rubber insert but the pulley will look rather different. It still has a flywheel outer and a   rubber insert.

 

I agree I would use the method above to free the pulley but I would use a socket and breaker/knuckle bar.

Correction.

 

You are correct Tony, some 1.5D have and some don't have a rubber damper, depends what they are originally out of.

Early ones in A60 cars did not have them I think. Perhaps BMC eventually discovered that the lack of a torsional damper broke the cranks when J4 PO van drivers thrashed them?

The bigger risk is the pulley fretting on the wood-ruff key, many do, leading to cracking in the pulley boss and lip seal destruction. Had several do this.

 

Apologies for the error and misinformation.   TD'

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2 hours ago, Tracy D'arth said:

Correction.

 

You are correct Tony, some 1.5D have and some don't have a rubber damper, depends what they are originally out of.

Early ones in A60 cars did not have them I think. Perhaps BMC eventually discovered that the lack of a torsional damper broke the cranks when J4 PO van drivers thrashed them?

The bigger risk is the pulley fretting on the wood-ruff key, many do, leading to cracking in the pulley boss and lip seal destruction. Had several do this.

 

Apologies for the error and misinformation.   TD'

 

Mmmm.... a knowledge of BMCs, as well as 50s / 60s vehicles and motor trade workarounds.  Quite tetchy and curmudgeonly responses to some posts.  I think we may have the true forum ID of "Tracy ".

 

Welcome back Sam.....

 

 

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  • 1 year later...

OK, so how do I find out if my BMC 1500 has one and can one be added if you change the crankshaft to the one with thin end plates ??

I do know the engine number, but no idea if it's a 1500D or not.

 

Not sure if my new pre abused and fully botched rebuild has had it changed or the crank inspected, although the top front pulley is new.

 

PS: Got a daft reply from ASAP, as they thought I wanted some kind of engine mount, and no reply from Calcutta boats etc.

Edited by TNLI
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Frankley if your contacts with this forum is typical of how you contacted Calcutt I am not surprised they do not reply.

 

Crankshafts do not have end plates but there are some mounted on the block. the "top pulley" is the engine water pump pulley and I suspect the pump might be a late addition. It has no relevance to the crankshaft.

 

I thought the cast flywheel housing was the same thickness as the steel back plate. 

 

I know there are different crankshafts depending upon the original purpose with some using a scroll and thrower seal and others a lip seal. Visual inspection with the flywheel off should make with obvious.

 

 

 

 

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  • 3 weeks later...

Still can't find a TB approved source of crank shafts and damper bearings, so if anyone knows where these parts can be found, apart from a scrap yard, please post it, just in case mine need to be replaced when they are inspected by the local experts. There is a good crankshaft inspection and repair company here, although no one in my area seems to have a Magnaflux crack detector.

 

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29 minutes ago, TNLI said:

Still can't find a TB approved source of crank shafts and damper bearings, so if anyone knows where these parts can be found, apart from a scrap yard, please post it, just in case mine need to be replaced when they are inspected by the local experts. There is a good crankshaft inspection and repair company here, although no one in my area seems to have a Magnaflux crack detector.

 

What are damper bearings? Do you know what you are talking about or is this all just Molly's gibberish?

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  • 1 month later...
On 04/03/2020 at 09:41, Tracy D'arth said:

The quick and unsafe way (  Professional? )  is to fit a ring spanner, free end over the port engine bed, and hit the start button with the stop button held in the stop position. 

Not recommended, do not try this unless you are very experienced in machinery and keeping yourself safe.

 

Under no circumstances grip the outer edge of a BMC 1.8D crankshaft pulley as Tony warned, else you will definitely  wreck the bonded rubber in the pulley and they are expensive. The  BMC 1.5D has no rubber.

Anyone know how to figure out if you have a BMC 1500 or a BMC 1.5D from the engine number ??

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  • 1 month later...

My old BMC 1500D is now with the local crankshaft and engine rebuild specialist company, and I hope to get an update about the crankshaft and main bearings inspection tomorrow sometime, BUT I was daft enough not to have mentioned that I want them to inspect the pulley torsional vibration damper. Now for the question, will they be able to see if it is badly worn or heaven forbid, split or cracked, without removing the pulley and front cover ??  In other words, can you inspect it from the inside??

  The chief engineer did say that he had never had a BMC 1500 turn up for a rebuild because of a failed crankshaft, so removing it to check it on their various test rigs was a waste of money, so he is just inspecting the main bearings and shaft from below, (I'm sure he will also look at the bearings, and if all is well we will be doing a full under load test run, before I try and find some chaps to drop the old donkey into its new home, with 2 bodged up engine mounting plates for sure. 

  So anyone got an opinion about what exactly can de done in inspection terms without taking the head off ??

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 I got the crank reground in the Perkins P6 in the Coles after it nipped up on two rods,without removing the head......obviously on most small motors you cant remove the pistons and rods from below............unless you ve got a LW Gardner ...pistons can be removed from below.

Incidentally,on little motors always check the rear main journal.......it gets a lot more wear than the rest,because of the heavy flywheel.

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3 hours ago, john.k said:

 I got the crank reground in the Perkins P6 in the Coles after it nipped up on two rods,without removing the head......obviously on most small motors you cant remove the pistons and rods from below............unless you ve got a LW Gardner ...pistons can be removed from below.

Incidentally,on little motors always check the rear main journal.......it gets a lot more wear than the rest,because of the heavy flywheel.

UMM, Errr,

  The Perkins does have a lot of parts in common but it has a very different crank, so not sure if the BMC crank can be dropped out or not. I just told the chief ginger beer, that the experts in the BMC canal forum say it can be dropped out without taking off the head. The starter motor and gearbox do need removing first, but that is normal for most small diesels, although the BMC manual does not list the gearbox removal in the crank related section.

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For goodness sake! All crankshafts on engines with sumps come out from the bottom but how much other work needs doing may vary from engine to engine. I think the 1.5 will need the timing cover (and thus the crank pulley off) the timing gear, the front plate, the flywheel, and the back plate & flywheel housing. You may be able to  wriggle the shaft out with the back plate in position but I am far from sure about that because I have never done it.

 

Then big end caps off, main bearing caps off and lift the shaft out. I THINK 1 & 4 pistons may come out from the bottom but I doubt 2 & 3 would. Anyway having stripped to that degree it would be as well to take the head of to draw the pistons the normal way and check surfaces for truth.

Edited by Tony Brooks
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Point of order.

 

The Kelvin J and K cranks come out from the front, complete with main hearings and housings.  The heads do not need to come off and the pistons and rods come out through the side doors. You can leave the oil system alone but all the gubbins has to come off the front and rear.

 

 The National DM and I think the Glenniffer DB/C  requires that you take everything off the bed plate then lift the crank out of the bed plate.  Never seen an RN DM dismantled, but expect it is like the National.

 

N

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1 hour ago, BEngo said:

Point of order.

 

The Kelvin J and K cranks come out from the front, complete with main hearings and housings.  The heads do not need to come off and the pistons and rods come out through the side doors. You can leave the oil system alone but all the gubbins has to come off the front and rear.

 

 The National DM and I think the Glenniffer DB/C  requires that you take everything off the bed plate then lift the crank out of the bed plate.  Never seen an RN DM dismantled, but expect it is like the National.

 

N

 

True, so I have edited my post to say engines with sumps. I know engines with proper crank cases tend to be different. I think the Volvo MD range has the crank and center main removed from one end. Once e get into the more exotic engines all sorts goes on.

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3 hours ago, BEngo said:

Point of order.

 

The Kelvin J and K cranks come out from the front, complete with main hearings and housings.  The heads do not need to come off and the pistons and rods come out through the side doors. You can leave the oil system alone but all the gubbins has to come off the front and rear.

 

 The National DM and I think the Glenniffer DB/C  requires that you take everything off the bed plate then lift the crank out of the bed plate.  Never seen an RN DM dismantled, but expect it is like the National.

 

N

 

Thanks for that, so just to get my brain cell in order before I leave to visit my beloved BMC 1500D, the routine for removing the crank shaft is as follows:

1/ Take the sump off, (Preferably after pumping the oil out)!

2/ Remove the TMP gearbox as per the TMP 100 instructions.

3/ Remove the front pulley.

4/ Remove the oil pump strainer and oil pump.

5/ Remove the bottom half of the 3 main bearings

6/ Drop the crank out of the sump hole, (The manual says otherwise, but could just be a different method).

7/ HEAD FOR THE TEST RIGS!

8/ Have a cup of tea and finally

9/ Get your ear bent about how bent it is and all the cracks.

10/ Buy a new crank and then head for the scrap yard for the pulley damper bearing.

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2 minutes ago, TNLI said:

 

Thanks for that, so just to get my brain cell in order before I leave to visit my beloved BMC 1500D, the routine for removing the crank shaft is as follows:

1/ Take the sump off, (Preferably after pumping the oil out)!

2/ Remove the TMP gearbox as per the TMP 100 instructions.

3/ Remove the front pulley.

4/ Remove the oil pump strainer and oil pump.

5/ Remove the bottom half of the 3 main bearings

6/ Drop the crank out of the sump hole, (The manual says otherwise, but could just be a different method).

7/ HEAD FOR THE TEST RIGS!

8/ Have a cup of tea and finally

9/ Get your ear bent about how bent it is and all the cracks.

10/ Buy a new crank and then head for the scrap yard for the pulley damper bearing.

3A remove front cover, cam sprockets and timing chain.

4A   remove the 4 big end caps!

4B Remove rear engine plate.

 

Otherwise you will not get it out!

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3 minutes ago, Tracy D'arth said:

3A remove front cover, cam sprockets and timing chain.

4A   remove the 4 big end caps!

4B Remove rear engine plate.

 

Otherwise you will not get it out!

Great thanks for that, the engineer already knows about the front and back, but I will mention the cam sprockets and timing chain.

 

So how long a job would you and the other BMC experts allow for removal ??

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