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Fitting Prestolite alternator to Shire 2002

I wish to fit a Prestolite 90A alternator to my Barrus Shire 2002 canal boat engine. Unfortunately the rear end of the prestolite will foul the waer cooled exhaust manifold. Some time ago on this forum someone had the same job done professionally. He too was worried about this problem but the professional installer got round it. Any ideas how? Has anyone else done this mod for themselves?
John Spicer

Asked by: John Spicer  | 4.38pm, Friday 25 October


WW says:

Your best bet is probably speaking to Barrus, as they might offer a ready-fit option for your engine.

Mark Langley  | 3.34PM, Wednesday 30 October


Readers say:

Sorted. First I was being overly pessimistic. Combining accurate measurements from a dimensioned drawing on the web with less accurate measurements taken in the engine compartment of a semi-trad narrowboat does not always give a good answer.
With the Prestolite 66021590M as delivered I would have had 1-2 mm clearance over the electrical connections on the rear of the alternator, but this is not really enough. The Prestolite has an adjustable pulley that can be moved along the shaft (a puller is NOT required) and by moving this back towards the body of the alternator I could bring the alternator forwards about 9.5 mm giving plenty of clearance. When doing this clearance must be left between the rim of the pulley and the fan. As a further change I fitted a slightly longer (1207 mm as opposed to 1157 mm) drive belt and swung the alternator out a bit. I now have unrestricted access to the electrical connections with the alternator in its working position. This does not seem to have affected the performance of either altenator.
The real mod I had to make was to the main mounting arrangement. The main mounting lugs are 30mm further apart than on the old Hitachi/Mando type and a longer bolt is needed plus some spacers to position the alternator correctly. A mixture of odd nuts and washers can be used but it looks better if one has access to a lathe so that proper spacers can be made. I have my own lathe so this was no problem.
I hope this willbe of use to others who are faced with the same problem

John Spicer  | 3.17PM, Wednesday 6 November

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