Third yotblog

Now it gets more interesting. From a mechanical point of view.

What engine do I put in. I just could not afford either a new one or a recon.  I used to be in engine reconditioning for most of my working life so I know just what has to be done  and for the life of me I CANNOT  get my head round the prices they want to charge,

So it had to be the second hand market.  OK  so be it…I searched Boats and Outboards. That seeming to be the best place. There were hundreds of engines of all sorts and sizes.

What were the requirements?

1        Diesel

2        Turbo

3        150/180 hp

4        Easy maintenance

There were several possibles. The one I liked from the start was a BMW 530.  This is the marine version of the car engine. 160 hp turbo. And it ticked all the boxes. I mentioned this to a good friend and he thought a bit and then said he felt there were problems with the genre. 

OK  What problems ?.

Overheating, leading to blown head gaskets and repairs were never satisfactory, leading to replacement heads. And those on enquiry were c £400 a piece.

Severe research was started. The result was amasing.  Yes, there were head gasket probs. But NOT on boats .. it was the car engine that gave the trouble.  Why?  Jammed in under the crowded bonnet, bad cooling…. The list goes on.  Also the marine version was linked to an outdrive unit. It was that that gave the problem.  So provided that the cooling was more than sufficient there should be no problems as the boat is shaft drive.

I decided to go and look at this engine. And hear it running.  It was a beautiful sunny day when we arrived at the place.  The engine was sitting on a palette with the water intake  hanging into a canal. The exhaust with about 4 ft of pipe.

It might be of interest to say that this engine had been put into a 60 ft narrow boat from new but was far to much for it, snick it into gear and your are doing 6 kts,,, a real NO NO for canals as I understand it, so out it had come. Salt water had never been through its internals.

It fired up. And I crawled all over it. The noise was …loud, but there was hardly any vibration at all. I could almost have stood an old threepenny bit on edge on it. BMW being noted for their engineering excellence. It had a full wiring loom with a brand new instrument panel, and massive hydraulic Hurth gearbox.

I had measured the engine bay on the boat and this would just fit in. A tight squeeze but in it would go. 

A deal was struck after some haggling and away we went. Me to arrange transport to the Isle of Man.

This engine is a 5 cylinder inline with separate heads. Which means it is a push rod engine not OHC, it maxs at 4250 rpm. But I think that around 3500 would be a good economical rpm.

Oh. we did all the prop calc stuff and talked to several wise people about which prop. It was interesting to see that only two of those asked actually agreed on which way to go. So  we now have ordered one, and hope to have it to hand about mid January. If this happens it will be very welcome, as this means I can then fit it and the rope cutter and finally lock the shaft coupling down tight.

Being a SD hull the normal max worked out at 6.5 kts with he old Perkins. This 160 hp will give us about 12/14 cruise with about 16 WOT. This is going to very interesting when we get to the sea trial stage.  That’s when theory gives way to practice.

The woodwork in the wheelhouse progresses. The dash panel is now installed with the seat and we are now working our way round panelling the sides below the window level. This is to create a warmer feel to it. This of course means a lot of rewiring, but that’s all to the good as some of it is years old and needed replacing.

It can be seen in the pix that I deliberately left the panel edges open rather than overlapping, this was so that I can fit quad beading of a different colour, and apart from the aesthetics it makes nice rounded corners.

That will be seen in the next blog.