Mac Wight engine


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    Peter LloydPeter Lloyd

    The 1.6 escort engine fitted to my Wight is causing me problems and I was wondering whether to have it overhauled or what I might replace it with. Any suggestions

    Also, as the PRM gearbox continues to works well, should I keep or should I also replace in favour of a single system


    Hi Peter.

    The original engine for the Wight was the Newage /Tempest BMC 1.5 D. Does that mean that your current engine is a replacement, or was your boat a custom build on a bare hull bought from MW? I personally always liked the BMC 1.5, which runs very sweetly. It has few    failings, and will usually give good long service.

    My current boat ( a 1986 Moody 37) has a Thornycroft T90 which is also based on the BMC1.5 D

    A good friend who has a Moody 422 had a Thornycroft based on the Ford 1.6D. He had issues with oil consumption and therefore blue smoke under load. He had it professionally rebuilt, fuel pump overhaul, etc. After a couple of years of intensive use, despite scrupulously respecting service intervals, the oil consumption issues were back again. He decided to rebuild using a Ford 1.8 , which has the same physical dimensions for the engine block, so the mounting brackets could be reused without modifying the engine beds.
    The lubrification and fuel injection pump are much better design, and have a reputation to be much more robust. Time will tell. Some accessories like the alternator and raw water pump drive are a bit different, but nothing that difficult to fix.

    Does that help you?

    Peter LloydPeter Lloyd

    Thanks Bob

    Yes, the original Newage engine was taken out in 2007 by the previous owner. As he was a car mechanic he converted a Ford 1.6D which until last year has been reliable and worked well. However, it increasingly smokes, at low revs. A service found the injectors had partly frozen, but then getting it restarted has highlighted an unevenness which has been put down to piston rings or valves. Although, I have not experienced blue smoke, oil does leak from the filler cap, so keeping the bilge water clean is difficult. However, oil loss over a year has been minimal.
    The question remains replace or repair (probable requiring a rebore).


    I believe that some rebuild parts for the 1.6 Ford ( pistons for rebore size) are difficult to source.

    be sure that everything is available before starting the project if you go for having your existing engine overhauled.


    Don’t forget that the Ford uses a camshaft timing belt that should be replaced periodically.
    I found the following about the 1.8 XLD:
    Other sources say that for the XLD , the cam belt should be replaced every 600h which doesn’t seem to be much. On cars, the consensus seems to be 5 years, or 60,000 miles.

    The worrying thing is that cam belt failure gives absolutely no warning before it comes, and usually causes serious damage to the engine.

    Peter LloydPeter Lloyd

    I have a mechanic friend coming to have a look at the engine at the weekend as I have been looking forward to sailing up the east coast and around to the Scottish western isles as soon as we are allowed. It was why I had it professionally serviced (including replaced cam belt) before lockdown but now out of lockdown find it no better. It had been running so sweetly at an average of 1.3lt/hr

    Your point about getting everything in order and available before starting is a good one. Thanks

    Peter LloydPeter Lloyd

    Good news. My mechanic friend reset the tappets and advanced the fuel injector pump 3 degrees and she is now running sweetly.  I am thinking the professional mechanic I had service my engine at the start of lockdown was trying to get a sale on a new engine!

    Now idling at 700rev and goes beyond 2,000 revs smoothly with little to no smoke. The sea trial also suggests I am getting better performance with 1.5kt when idling and ~6kt at 2,000. Also found where oil has been leaking from, so hopefully a clean bilge as well.

    Thanks for your assistance. Peter



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