Sam, this reminds me of when I was doing the engine swap on a Corsa. I had to change the head gasket as well and as I was fitting the timing chain (the 1.2 engines have a timing chain) the tensioner which was under compression came off and ended up in the sump. Fortunately, I managed to fish it out with a telescopic magnet. The bottom of the timing chain cover mates up with the sump and the 1850 engine is similar. I've been looking in the parts catalogue and the shallow part of the sump is under the timing chain so the nut might be resting on there if you're lucky. Keep on trying with the magnets and if you still have no joy then it will be sump off to retrieve the nut.
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Toledo Man
West Yorkshire Area Organiser & forum moderator
Meetings take place on the first Wednesday of the month at 8.00pm at The Old Brickworks, Wakefield Road, Drighlington, Bradford, BD11 1EA
1972 Dolomite 1850 auto (NYE 751L - Now for sale)
2003 Volvo XC90 D5 SE (PX53 OVZ - The daily driver)
2009 Mercedes-Benz W204 C200 CDI Sport (BJ58 NCV - The 2nd car)
1991 Toyota Celica GT (J481 ONB - another project car)
Former stable of SAY 414M (1974 Toledo), GRH 244D (1966 1300fwd), CDB 324L (1973 1500fwd), GGN 573J (1971 1500fwd), DCP 625S (1977 Dolomite 1300) & LCG 367N (1975 Dolomite Sprint) plus 5 Acclaims and that's just the Triumphs!
Check my blog at
http://triumphtoledo.blogspot.com
My
YouTube Channel with a bit of Dolomite content.
"There is only one way to avoid criticsm: Do nothing, say nothing and BE nothing." Aristotle