Replacing Engine mounts Barrus Shire 45

[TeeELL]

Hi,

  I’ve a suspicion that one or more of the engine mounts on my BS 45 have reached the end of their life.  As I am out cruising, I am wondering if it is feasible to change them a pair at a time, to reduce the likelihood of thing getting out of alignment.  Advice, words of wisdom, guidance etc gratefully received - especially from anyone who has done it!  Thanks.

[Bee]

If you've got a Python drive / Aquadrive then you should be fine to change them a pair at a time. If you don't then I would try to do all 4 and try very hard to keep it in line and also diagonally equal  to avoid engine wobble. It can be quite awkward.

[Tracy D'arth]

Don't try to get away without fully re-aligning the engine unless you have a constant velocity drive like an Aquadrive or Python. You need to align on 2 dimensions and be axially in line at the same time.

[TeeELL]

Sorry, I did forget to say I have a Python drive!  Thanks for the advice thus far guys/gals.   I assume there is a need to disconnect the Python from the gear box (remember - there is no such thing as a stupid question! Lol).  Just need to determine how 

 

Tracy, love your ‘bottom line tag’.

Edited May 28, 2023 by TeeELL

[Tony Brooks]

23 minutes ago, TeeELL said:

Sorry, I did forget to say I have a Python drive!  Thanks for the advice thus far guys/gals.   I assume there is a need to disconnect the Python from the gear box (remember - there is no such thing as a stupid question! Lol).  Just need to determine how 

 

Tracy, love your ‘bottom line tag’.

 

If it is a "long stud up through the engine foot" then you probably will have to disconnect the drive unless you can get the stud out of the mount. If the engine foot sits on the mount with a bolt through it then both those drives should allow enough "lift" so you do not need to disconnect them.

[TeeELL]

Tony,

  thank you.  I feel this has fallen outside my capabilities and on-board resources, not to mention that I am nowhere near a chandlers.  I am going to take it slow and try Alvecote Marina Services because, being BH Monday, Springwood Haven will be closed.

[Tony Brooks]

5 minutes ago, TeeELL said:

Tony,

  thank you.  I feel this has fallen outside my capabilities and on-board resources, not to mention that I am nowhere near a chandlers.  I am going to take it slow and try Alvecote Marina Services because, being BH Monday, Springwood Haven will be closed.

 

The difficulty is getting the engine high enough to get the mount out.  If the engine is suspended on a nut below the foot with a long stud sticking up through the foot then I agree many would get it done professionally. If all you can see on top of the foot (the bracket fixed to the engine) is a hexagon and washer, then it is relatively easy to do by levering the engine up a mm or so and sliding the old mount out and the new mount in. I used a mooring stake over the engine bed when I did mine.

[TeeELL]

Tony,

  again thank you.  I still have to get to a chandlery to obtain the bits!  I will send a photo, if I may, for you opinion.   However, my revised plan is to cruise the short distance to Star-line boats and see if there is anyone around and, maybe stay over night and see what they can do tomorrow.

Truth to tell, the items have been in since new and I should have changed them after last years cruise - but it completely slipped my mind (no, to be honest I completely forgot!).

[Tony Brooks]

Why do you think the mounts are at the end of their life? I can see that could be the case if any have been contaminated by fuel or oil, but with a Pythondrive the mounts are not subject to constant flexing from prop thrust, so could last tens of years. The front mounts on my Bukh with an Aquadrive lasted 30 years and as far as I know are still going.

 

By all means post photos, but take them in a low resolution to save having to crunch them before sending. many images from modern phones are too large for the forum.

[TeeELL]

Tony,

  the mounts are 20 years old.  The reason for my concern about their state - I was investigating why my oil pressure warning was on and gauge reading zero, in so  doing I found that when I put my weight on the engine ‘step plate’ the readings returned to normal.  I realised that there was excessive vibration which can be felt throughout the boat. 
Here is a photo of the front starboard mount:

 

[Tony Brooks]

Thanks, not a lot of help other than to say it is a stud type, so the engine will have to be lifted higher, unless the stud unscrews from the mount, but even if it does there is probably another nut below the engine foot that will hinder unscrewing the stud so your plan to pay is probably best.

 

I am not sure what the engine step plate is, I suspect it is the exhaust manifold and something I would not be putting my weight on. The mounts have nothing to do with the oil pressure gauge, so I would suspect that is probably a loose connection on the sender. If it is a push on blade type, they can be gently squeezed closed a little.

 

The vibration may well be caused by a collapsed mount allowing the stud or what it screws into to hit the steel engine bed, but if those studs are removable, then someone may have screwed one too far into the mount. Before spending any money, make sure the two or four smaller nuts and bolts securing each engine mount to the bed are nice and tight. They can cause vibrations when loose.

[TeeELL]

Tony,
OK, thanks.

1.  engine step plate is a chequer plate panel fitted on the top of the engine to allow it to be stepped on if required/

2.  no one has touched the vibration mounts.

 

I will check the tightness of the nuts as you suggest but I have a suspicion that the mount(s) have collapsed.

 

Thank you very much for your advice, it is very much appreciated.

[TeeELL]

The nuts underneath are nylock with the addition of a lock washer - no movement there.

[Tony Brooks]

53 minutes ago, TeeELL said:

The nuts underneath are nylock with the addition of a lock washer - no movement there.

 

Not sure what you mean. You probably have big nuts underneath the engine foot on that big stud, but they are not usually nyloc. The nuts and bolts that hold the engine mount to the bed may have nyloc nuts on them, just make sure we are talking about the (say) 8mm bolts that hold the foot to the bed. If they are tight, then that will not be the problem.

[ditchcrawler]

13 hours ago, TeeELL said:

Tony,

  thank you.  I feel this has fallen outside my capabilities and on-board resources, not to mention that I am nowhere near a chandlers.  I am going to take it slow and try Alvecote Marina Services because, being BH Monday, Springwood Haven will be closed.

So will Alvecote, but I guess they will be open in the morning

[TeeELL]

Ah!  I get it Tony.  The engine is, of course, mounted onto the 2 steel L plates those, in turn, are attached to the boat via the rubber mounts.

[Tony Brooks]

I don't think that you do fully get the terminology, look at this

 

 

The engine bed is usually an inverted steel L section welded to a metal's boat hull, the baseplate for the narrowboat. On other types of boat it could be a large rectangular section of wood or GRP.

 

The green plate on the big stud between the two nuts is the engine foot, and it could well be a long L section fixed to the engine.

 

You can also see the two, in this case, smaller bolts holding the mount (large green & back bit) to the bed that I asked you to check for tightness.

 

As for the lever and block of wood that is used to check the amount of lift in the rubber, it should not be very much at all, but it takes a bit of experience to tell what may be too much. Your vibration suggests it might be on one or more mount, but it could be the big stud has been screwed too far into the mount on certain types.

 

 

 

[TeeELL]

Tony, 

 the engineer at Star Boats has been over and had a look.  One rubber mount has collapsed completely and one is twisted.  He is off to get hold of replacements so I am hopeful that things might be resolved no later than tomorrow.

Thank you so much for your help in this matter, it is very much appreciated.  Once this issue is resolved I will report it so and declare this thread closed.

[TeeELL]

One mount out - not even the collapsed one - it is ‘orrible!  The boss of the yard will be off to Midland Chandlers (the main base in Nuneaton is only a couple of miles away), to pick up replacements.

Having seen what Spec (the engineer) is having to do and use, the job is definitely not something I have the equipment to deal with.  Some of the difficulty is the shouldered bolts used by the original fitters, making undoing them a lengthy task.

In addition, it seems every nut isn’t just tight or even very tight - they have been done up by Arnold Shwarenegar.

[TeeELL]

All the mounts removed - which took some doing!  Unfortunately having to go to EP Barrus, Bicester for replacement parts :(.  They will not get here until Thursday late morning as a mate is couriering them to me.    Should have everything back together in a fraction of the time it took to get it apart.

Tony,

  sorry for using the wrong terminology, I flew military aircraft for a living!  My knowledge of the finer points of narrowboat engine parts is poor but getting better.

Things should be resolved by Thursday.

[Tracy D'arth]

Have you arranged a mortgage to pay for the part? Some of Barrus'  spares are an eyewatering price.

[Tony Brooks]

1 hour ago, TeeELL said:

  sorry for using the wrong terminology, I flew military aircraft for a living!  My knowledge of the finer points of narrowboat engine parts is poor but getting better.

Things should be resolved by Thursday.

 

no problen for me, I just wanted to avoid you signing yourself as ripe for ripping off as can happen if the punter shows a lack of knowledge. I would be the same trying to discuss flight control systems.  Hope it all works out.

[TeeELL]

‘Spec’ the engineer at Star Line boats insisted on checking - he had another customer with a similar problem last week;  after the check he was able to reassure the customer that his issue lay elsewhere.  His comment to me ‘it makes a pleasant change to find a customer who’s diagnosis is spot on’.  We worked together to remove the old parts - and they do show serious signs of distress.

59 minutes ago, Tracy D'arth said:

Have you arranged a mortgage to pay for the part? Some of Barrus'  spares are an eyewatering price.

Tracy, I have ‘a few bob’ in reserve and I am sure I can survive with one kidney!  Lol ‘Be Over Another Thousand’!

Thank goodness for Royal Air Force pensions!

[TeeELL]

Tony,

  am I correct, that the nut under the ‘engine foot’ is used to create the vertical adjustment for the engine alignment, thus that nut and its 3 partners carry the mass of the engine.

Oh,  I can now appreciate why my photo was of no use whatsoever.  It is quite amazing how, having seen the part how much more obvious your explanations have been.  I have now learned a little more about my boat.  

[Tony Brooks]

Yes, absolutely correct, remember that when setting the engine up, the Pythondrive and Aquadrives need to run slightly out of line, so the lubricant inside is moved about over the balls and grooves. Near enough inline will do, unlike most other shaft couplings. If the shaft installation allows it I would keep the bottom nut as far down the stud as I could to minimize the leverage provided to the engine vibrations to stress the rubber. This is in a perfect world, you will have to do your best with what you have,

 

Anyway, hopefully some nice smooth cruising not too far away,