JNW3 449 Posted November 4, 2017 Report Share Posted November 4, 2017 Are there any dry sump owners on here who could help with my search for a drive belt for the oil pump for my 1980 Essex? Have already tried Lotus and SJ but no joy so far - any suggestions greatly appreciated as these appear to be harder to come by than hens teeth! Quote Link to post Share on other sites
Gold FFM Dan E 1,582 Posted November 4, 2017 Gold FFM Report Share Posted November 4, 2017 I had this chat with Gerald at GST he didn’t change my belt as it apparently is in great condition but I am pretty sure he knows where to find them or the equivalent. Give him a call (don’t email he doesn’t do email) he is a lovely chap and I am sure he will help you if he can 1 Quote Link to post Share on other sites
Gold FFM johnpwalsh 1,346 Posted November 4, 2017 Gold FFM Report Share Posted November 4, 2017 mmm, so your running old belts then. tut tut, be wary of slippage, it can happen when the become polished. Quote Link to post Share on other sites
Gold FFM Dan E 1,582 Posted November 4, 2017 Gold FFM Report Share Posted November 4, 2017 Mate if Gerald says it ok that’s good enough for me. 1 Quote Link to post Share on other sites
Timjgor90 16 Posted November 4, 2017 Report Share Posted November 4, 2017 Sj’s do a drive belt for the oil pump on a dry sump but it is only 1 size so might not fight some cars, but I’ve bought one for my dry sump and it’s the same size etc as the old one that came off so maybe order one and try it and see. Quote Link to post Share on other sites
JNW3 449 Posted November 4, 2017 Author Report Share Posted November 4, 2017 Hi Tim - already tried the SJ belt and it doesn’t fit needless to say! Quote Link to post Share on other sites
Gold FFM johnpwalsh 1,346 Posted November 4, 2017 Gold FFM Report Share Posted November 4, 2017 Take your old original belt to an old style motor factors and they should be able to match it up for you. Quote Link to post Share on other sites
Barrykearley 6,988 Posted November 4, 2017 Report Share Posted November 4, 2017 6 hours ago, JNW3 said: Are there any dry sump owners on here who could help with my search for a drive belt for the oil pump for my 1980 Essex? Have already tried Lotus and SJ but no joy so far - any suggestions greatly appreciated as these appear to be harder to come by than hens teeth! Try an agri factors - any belt any size should be simple to acquire https://www.bearingboys.co.uk/Transmissions-1001-c 1 Quote Only here once Link to post Share on other sites
JNW3 449 Posted November 4, 2017 Author Report Share Posted November 4, 2017 Thanks for the suggestions gents - the only issue we have is that the belt currently on the car is not an original Esprit part and doesn’t fit properly so can’t be copied frustratingly Quote Link to post Share on other sites
Gotti 205 Posted November 4, 2017 Report Share Posted November 4, 2017 In the topic "Essex 007" i read that the previous Australian owner installed an aftermarket tensioner years ago.Is it no longer present? My engine is currently under rebuild and i bought the drive belt from "SJ" too.We will build an eccentric tensioner for the oil pump drive belt.This might be the best option for the future.... 1 Quote Link to post Share on other sites
TAR 406 Posted November 4, 2017 Report Share Posted November 4, 2017 Sorry I can't help you finding a belt but I do wonder why Lotus made different lengths and differing pulleys. Anyone know why this would be? Quote It's getting there...... Link to post Share on other sites
Steve4012 190 Posted November 6, 2017 Report Share Posted November 6, 2017 Hi Jonathan, I'm currently removing my engine and here's what I have on my '81 dry sump. It's a powergrip 41060 16mm. Hope that helps. Hope your cambelt is better than mine! (There are splits all the way along the belt ) Cheers, Steve. 1 Quote Link to post Share on other sites
Andyww 1,291 Posted November 6, 2017 Report Share Posted November 6, 2017 On 04/11/2017 at 20:11, TAR said: Sorry I can't help you finding a belt but I do wonder why Lotus made different lengths and differing pulleys. Anyone know why this would be? Because there is no tensioner, so they had to select exactly the required size for proper tension. If someone has found a way to add a tensioner that would be good but it needs to be a 100% reliable setup owing to the disaster if the belt comes off! Quote Link to post Share on other sites
Gotti 205 Posted November 6, 2017 Report Share Posted November 6, 2017 1 hour ago, Andyww said: Because there is no tensioner, so they had to select exactly the required size for proper tension. If someone has found a way to add a tensioner that would be good but it needs to be a 100% reliable setup owing to the disaster if the belt comes off! I,ll take some pictures (and a short video) when my engine is ready and post them in the "restoration" section.We would like to use the eccentric tensioner and bearing from Lotus and fit (maybe machining)them to the A/C compressor bracket which is mounted at the bottom of the sump.So its the same bearing as for the automatic cam belt tensioner.It will most probably still take some time until the engine is ready.I hope before Christmas. Quote Link to post Share on other sites
TAR 406 Posted November 6, 2017 Report Share Posted November 6, 2017 3 hours ago, Andyww said: Because there is no tensioner, so they had to select exactly the required size for proper tension. If someone has found a way to add a tensioner that would be good but it needs to be a 100% reliable setup owing to the disaster if the belt comes off! That doesn't make sense. as both the oil pump pulley and the crankshaft pulley are fixed so the belt would be the same for all cars. Lotus did belts that were both plus and minus sizes and they also supplied oil pump pulleys with differing numbers of teeth (differing circumference). Why bother with all that complexity? Quote It's getting there...... Link to post Share on other sites
Andyww 1,291 Posted November 7, 2017 Report Share Posted November 7, 2017 9 hours ago, TAR said: That doesn't make sense. as both the oil pump pulley and the crankshaft pulley are fixed so the belt would be the same for all cars. Lotus did belts that were both plus and minus sizes and they also supplied oil pump pulleys with differing numbers of teeth (differing circumference). Why bother with all that complexity? Tolerances. The oil pump is a bolt-on unit so its own mounting face machining tolerance, the face on the scavenge manifold, and on the main bearing housing would all affect tension as would gasket/sealant thickness. Its very likely that Tony Rudd didnt design it to use selected belt lengths but they likely found in production they needs to select the belts. Quote Link to post Share on other sites
TAR 406 Posted November 7, 2017 Report Share Posted November 7, 2017 so I'm happy with the explanation for the belts but why the differing pulleys? With various belts surely you wouldn't need a selection of pulleys? 13 hours ago, Andyww said: Tolerances. Quote It's getting there...... Link to post Share on other sites
Andyww 1,291 Posted November 8, 2017 Report Share Posted November 8, 2017 Because the pulley and belt combination would define the tension. The differences in belt lengths were likely too great to adjust the tension by the small amounts required, so a combination of the two changes, pulley and belt had to be used. Not at all an ideal situation for a production environment! This kind of thing would be OK for an F1 engine. Incidentally the dry-sump system is very similar to that of race engines such as the Cosworth DFV. I am not sure how many other road cars have ever used a design such as this. The Ferrari 308 early cars had so-called dry sump which were not actually dry sump at all. They still had a full sump wheras the Esprit has no sump at all. 2 Quote Link to post Share on other sites
Gotti 205 Posted November 29, 2017 Report Share Posted November 29, 2017 The belt from Sj is too loose without a tensioner.The dry sump a/c bracket is perfect to fit an eccentric (Lotus) one.Its not finished yet but i took a photo today. Quote Link to post Share on other sites
Gotti 205 Posted December 12, 2017 Report Share Posted December 12, 2017 How tight should the dry sump drive belt be?Does anyone have experience? Quote Link to post Share on other sites
Andyww 1,291 Posted December 13, 2017 Report Share Posted December 13, 2017 Sorry this is off-topic but thats a beautiful looking engine! Did you paint the castings out of interest or vapour-blast or some other method? Quote Link to post Share on other sites
Gotti 205 Posted December 13, 2017 Report Share Posted December 13, 2017 I, m not sure, my rebuilder made everything.I think he said dry-ice blasting....Do you know how tight the dry sump drive belt should be? Quote Link to post Share on other sites
Andyww 1,291 Posted December 13, 2017 Report Share Posted December 13, 2017 Difficult question to answer without being vague but I would say not very tight. Quote Link to post Share on other sites
drdoom 421 Posted December 14, 2017 Report Share Posted December 14, 2017 Hi Jonathan, I follow this with interest as I salvaged a dry sump motor from an insurance write-off Turbo which I happened upon by chance. It is to find a new life in the bay of my S2, now in the long grind of total restoration. As to belt tension I believe the guiding principle in this is to think of a cog belt as something of a flexible gear train, or chain drive if you prefer. Slippage is not to be abided under any circumstance so it should never be run loose. I have been told that the backwards bend arising out of use of a tensioner is contrary to belt life, though designs of the sort are ubiquitous. Absent any sort of effective tensioner I would seek to set up the belt with a decidedly firm level of tension. Don't know how to quantify this but perhaps the old 45 degrees of twist by fingers at the limit of strength? Enormously powerful Harley-Davidson motorcycles often piloted by really large chaps are driven via cog belt, for those who may not have noticed. Cheers Steve Quote Link to post Share on other sites
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