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TR2/3/3A TR3A FUSES
- Thread starter Alvin
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TR3driver
Great Pumpkin - R.I.P
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I believe by 59, the horn fuse had dropped to 35 amps, meaning both fuses in the fuse block were 35 amps, while the in-line holder under the dash (if present) was 25 amps. Earlier cars had a 50 amp fuse for the horns.
Note : <span style="font-weight: bold">these ratings are in the obsolete Lucas/BS fuse rating system!</span>
They are roughly twice the rating of a comparable American standard fuse.
IOW, an AGC 20 is a suitable substitute for the specified 35 amp, while an AGC 25 may be used in place of the 50 amp. This is particularly important to know if you are on the road and need a replacement fuse.
'Correct' Lucas-equivalent fuses (which are also slightly smaller physically than the AGC fuses) are available from the usual suspects.
Note : <span style="font-weight: bold">these ratings are in the obsolete Lucas/BS fuse rating system!</span>
They are roughly twice the rating of a comparable American standard fuse.
IOW, an AGC 20 is a suitable substitute for the specified 35 amp, while an AGC 25 may be used in place of the 50 amp. This is particularly important to know if you are on the road and need a replacement fuse.
'Correct' Lucas-equivalent fuses (which are also slightly smaller physically than the AGC fuses) are available from the usual suspects.
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I don't know what the most current Lucas fuses say, but the "original" ones simply said 35 (50) amp on the paper inside. Sometime in the 1970s or 1980s (not sure when) the line "17 (25?) amps continuous" was added, probably so that folks wouldn't be so tempted to replace the blown 50 (25 continuous) with an American Buss 50 amp fuse.
Compare on current eBay auctions:
350307110300 (newer)
360120789602 (older)
Compare on current eBay auctions:
350307110300 (newer)
360120789602 (older)
Geo Hahn
Yoda
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Since the fuse block on a TR3 is so visible I like to use the original style or a repro of same:
These can be made by opening up modern Lucas fuses and inserting old-style papers. Pretty simple really.
Can also be done using modern Buss fuses -- the conductor will be a blade rather than a wire but is mostly hidden by the label.
Though the modern 20-amp Randall suggests is closest, if you use a 14-amp for this label substitution the length of the fuse will be more like the old Lucas fuses. I have never had a problem with using the 14-amp fuses in the 3 but then I'm not running any significant non-stock loads.
These can be made by opening up modern Lucas fuses and inserting old-style papers. Pretty simple really.
Can also be done using modern Buss fuses -- the conductor will be a blade rather than a wire but is mostly hidden by the label.
Though the modern 20-amp Randall suggests is closest, if you use a 14-amp for this label substitution the length of the fuse will be more like the old Lucas fuses. I have never had a problem with using the 14-amp fuses in the 3 but then I'm not running any significant non-stock loads.