JanetAnne Posted April 27, 2023 Share Posted April 27, 2023 Help!! I have a 4108 spread over a wide area and am having problems matching and locating the valve stem seals currently fitted. I know Perkins used o rings on the inlets only and I have those but this engine has what I would call proper caps, (photo below). Obviously Perkins can't supply these as they don't exist in the relevant parts book... I have a copy from Prior Diesels.... so I am wondering whether this was a common modification and, if so, would you have any idea of the original fitment of the seals used? Of course, once upon a time I'd just pop along to stores and ol' Fred would disappear out back and match them but, sadly, these days you need a computer degree just to get into stores and holding my pattern up in front of the screen and saying "I want one like this" didn't work, believe me I tried! Cheers mate Quote Link to comment Share on other sites More sharing options...
JanetAnne Posted April 27, 2023 Author Share Posted April 27, 2023 Forgot piccys Quote Link to comment Share on other sites More sharing options...
Smoggy Posted April 27, 2023 Share Posted April 27, 2023 You need a proper old school engine shop where the old guy in his arkwright coat will measure the ID and OD and say "this'll fit mate", unfortunately they are few and far between now as most "mechanics" are actually just fitters and will sell you a new head or complete engine only. Or Vaughan..... 1 Quote Link to comment Share on other sites More sharing options...
Hylander Posted April 27, 2023 Share Posted April 27, 2023 Vaughan is still on the coffee and croissants. 2 Quote Link to comment Share on other sites More sharing options...
Vaughan Posted April 27, 2023 Share Posted April 27, 2023 Sorry mate, I can't help with that one. Never seen one like it! I know the marine 4108 was the same as the vehicle engine as we often used to buy them from a car breaker (Hainford Hall) and re-build them. The only difference was the marine sump, which also meant a different (deeper) oil pump. The marinised engines also have a larger flywheel and bell housing, with the starter motor on the other side. We all used to get our parts from Duffields on the airport estate in Norwich. They were the Perkins main dealers and also developed the MC42 engine. Sadly they are no longer. All I can say is I am pretty sure it is not a "marine" part. Quote Link to comment Share on other sites More sharing options...
Smoggy Posted April 27, 2023 Share Posted April 27, 2023 Measure valve stem and guide OD and get hunting, it'll be from a completely different engine at a guess, I wonder if the 1.5 or 2.52 bmc's would have used a similar size. 1 Quote Link to comment Share on other sites More sharing options...
Vaughan Posted April 27, 2023 Share Posted April 27, 2023 34 minutes ago, Hylander said: Vaughan is still on the coffee and croissants. I remember when I was truck driving in France, starting about 4.AM and sometimes calling in at a Routier restaurant to take a break and a coffee and croissant. There would be a line of big fat French truckers sitting at the bar, most of them asking for "Un petit café, et une pousse". Pousse meaning "a push" - which meant a large glass of Cognac. At 6.30 in the morning! 1 1 Quote Link to comment Share on other sites More sharing options...
AndyTBoater Posted April 27, 2023 Share Posted April 27, 2023 Umbrella Seals??? Are these just a loose(ish) fit on the stems? I seem to remember someone (probably you) telling me they were a "leak reduction gizmo" and designed to slow down the ingress of oil to the valve stems rather than a seal. Or I could just be making this up https://www.parts4engines.com/ were really helpful when I was doing bits to my Stuart Turner. 2 Quote Link to comment Share on other sites More sharing options...
Vaughan Posted April 27, 2023 Share Posted April 27, 2023 7 minutes ago, AndyTBoater said: Are these just a loose(ish) fit on the stems? I seem to remember someone (probably you) telling me they were a "leak reduction gizmo" and designed to slow down the ingress of oil to the valve stems rather than a seal. I have been reflecting on this and think you are right. They were designed as a sort of hood, to deflect the oil coming down from the rocker shaft and keep it away from the valve stems. I possibly don't remember them much, as I think they were usually left off! Quote Link to comment Share on other sites More sharing options...
MargeandParge Posted April 27, 2023 Share Posted April 27, 2023 Give Maffett desires a ring in Loddon . Regards Marge and Parge Quote Link to comment Share on other sites More sharing options...
MauriceMynah Posted April 27, 2023 Share Posted April 27, 2023 50 minutes ago, Vaughan said: Pousse meaning "a push" - which meant a large glass of Cognac. At 6.30 in the morning! At last! I've now heard something French I approve of. 6 Quote Link to comment Share on other sites More sharing options...
WherryNice Posted April 27, 2023 Share Posted April 27, 2023 Those seals look very similar to the ones that were supplied to us in a 'Top end set' from parts4engines(for a 4108). It also came with the O rings. We fitted the lot but I was a bit unsure about the larger ones as they just seemed to sit on the valve with nothing to locate them properly but as the engines smoking habit was much reduced we left them fitted. 1 Quote Link to comment Share on other sites More sharing options...
floydraser Posted April 27, 2023 Share Posted April 27, 2023 4 hours ago, Smoggy said: You need a proper old school engine shop where the old guy in his arkwright coat will measure the ID and OD and say "this'll fit mate", unfortunately they are few and far between now.... Or maybe alive and well and you'll find him at a classic tractor or lorry show with boxes of old stock parts. 1 Quote Link to comment Share on other sites More sharing options...
annv Posted April 27, 2023 Share Posted April 27, 2023 Hi Valve stem seals are not designed to seal but stop to much oil running down the stem and being sucked into the combustion chambers, BMC seals do seal but they are fitted under valve cap collets as the top of the valve spring cap is dished and collects oil. Perkins ones are just a shroud to stop to much oil running down the inlet valve, you need some on the stem for lubrication purposes. if old ones are just hard but complet reuse them, at worst you my use a little more oil, worn valve stems are much more likely oil users, keeping the valve cover clean with yearly oil changes is much more important to stop a build up of crud around the valves as well as removing acides from the oil when engines are under used.This highlights the best practise to have a stock off consumables items while still available on older less common engines. Have you tried boat yards or engine reconditioners. There's one or was one at Soham Nr Ely Cambs.( afraid i have forgotten the name) John Quote Link to comment Share on other sites More sharing options...
Smoggy Posted April 27, 2023 Share Posted April 27, 2023 I'll bet anglian engines in St.neots has done plenty of 4108's in their time, maybe worth a call. Quote Link to comment Share on other sites More sharing options...
annv Posted April 27, 2023 Share Posted April 27, 2023 Hi Just remembered they are called Ivor Searle I didn't use them my self as we did our own reconditioning , They are a large business so may be able to help. John Quote Link to comment Share on other sites More sharing options...
Lulu Posted April 27, 2023 Share Posted April 27, 2023 30 minutes ago, annv said: Hi Just remembered they are called Ivor Searle I didn't use them my self as we did our own reconditioning , They are a large business so may be able to help. John https://www.ivorsearle.co.uk We live quite near to Soham. Have heard positive feedback about them Quote Link to comment Share on other sites More sharing options...
JanetAnne Posted April 27, 2023 Author Share Posted April 27, 2023 Thanks everyone for both your input on this thread and via PM's. Collectively you managed to put me on the right track and we now have the correct parts on order. 2 Quote Link to comment Share on other sites More sharing options...
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