billy_anorak59 Posted May 31, 2023 Share Posted May 31, 2023 7 minutes ago, Jol Wilkinson said: It think that expansion tanks don't normally have pressure caps. The feed to the tank looks like it is from the radiator overflow outlet. So all that the tank cap is doing is pressurising the tank and hose to the radiator. + It looks that the top of the radiator is below the top hose into the engine so it may be that the expansion tanks stops air being drawn in to the radiator when cooling down. But it still should't need a pressure cap. Hmm - Interesting that. Taking a look at the Rimmer Brothers diagram as well as a photo of an actual Vitesse engine bay, it would appear that the expansion tank does need a cap, but the radiator iself does not: A 'Specimin' engine: Does that mean that my radiator is 'wrong', and can I effectively blank the radiator by having a cap that is just a cap, i.e. a 'solid' cap with no pressue release? Is there such a thing? I do wonder what's going on here, as I was told that the whole engine/gearbox came from a crashed 1965 Vitesse (on the M6) - and I 'presumed' (I know - never presume) that the cooling system would have been from the same car, but it looks like it may have actually been replaced. Thanks for making me look properly! More thinking needed...(apologies if none of this is interesting to other folk - it wasn't my intention to hijack the thread) 2 2 Link to post Share on other sites More sharing options...
RMweb Gold Nick C Posted May 31, 2023 RMweb Gold Share Posted May 31, 2023 AFAIK you only need one pressure cap, usually at the highest point - it looks as though you effectively have two expansion tanks, one on the rad plus a standalone one, each with their own cap. I would imagine there's a way to work out how much expansion space you need for a given size of engine, but I don't know what it is! 4 1 Link to post Share on other sites More sharing options...
Jol Wilkinson Posted May 31, 2023 Share Posted May 31, 2023 Probably, in your kit car the hot, expanded, water from the radiator will lift the cap spring and pass out through what is normally the overflow pipe into the expansion tank. On cooling it will be drawn back through the air valve in the middle of the cap. However, it looks as though there is also another pipe directly from the radiator to the expansion tank (alongside the "overflow" pipe). So you could effectively blank off the cap on the top of the radiator, in which case the system would be like that in the Rimmer Bros. diagram. It may be that you have the correct radiator for your car, but someone has used the Vitesse header tank that was presumably on the engine when it was recovered from the crashed car. If it works okay. it might be best to leave it alone. Alternatively, if the radiator top tank is high enough for the cooling system yo function without the expansion tank, you could remove that. Rather than replace the radiator cap with a "solid one - if such exist - you could get the radiator cap "pipe" on the rad removed and the hole plated over. This was the sort of thing you could easily get done when the car was being produce, radiator repair companies existing in most town. 3 Link to post Share on other sites More sharing options...
billy_anorak59 Posted May 31, 2023 Share Posted May 31, 2023 Food for thought there to mull over @Jol Wilkinson@Nick C - thanks for the input - appreciated! Time to think a bit more. 1 Link to post Share on other sites More sharing options...
alastairq Posted May 31, 2023 Share Posted May 31, 2023 (edited) I think something is a bit 'lost' in definitions here? In the photo above [specimen?] the tank is really a 'header'' tank...equivalent to, say, the top, raised part of an old school car radiator, which has the cap & overflow outlet combined. A problem with low bonnet lines, perhaps? An 'expansion' bottle [tank?] is a container fed by the radiator overflow [from the header' tank, or radiator top]... The inlet [overflow pipe ] will go into the expansion tank, at the bottom [or, via a log enough hose to reach the tank's bottom]....At the top of the expansion tank will be another overflow pipe, going to the atmosphere. The expansion tank will not [normally] have a pressure cap of any sort. That will be on the radiator proper. The expansion tank will catch the expanded hot coolant [which is why one should not 'fill' an expansion bottle]....and return coolant as the car cools down, via vacuum. This keeping the radiator topped up all the time. I should add, some radiator caps also come with a small vent to allow air out or in, usually a small button on the top middle...Others don't have this feature. If using an ''expansion'' tank system, then the rad cap on the radiator, whilst a pressure cap, should have no other vent in its top. Same with the 'solid' caps, as I found out 30 years ago! Made a nonsense of a n expansion bottle system if the rad cap allows the air back in when cooling down...rather than vacuum drawing coolant from teh expansion bottle/tank. A 'header' tank can be part of the cooling system's pressurised circuit. Provides a 'head' of coolant above the radiator, or other highest point in the system. Both my dailies [Daihatsu 4Trak, & Suzuki Grand{!} Vitara [mk 1 GV]...have very tweeny pressure caps on the radiator tops [top tank]...and expansion bottles nearby. When the small cap is opened [only when cool].... the level of coolant is always right to the top. This level is maintained by the suck n blow of the expansion bottles. My Cannon has a cooling system [or, did have?] similar to the sample Vitesse system above...in that the radiator has no 'top' tank, as such [mini rad on its side...cheap n cheerful, me], so needed a header tank to provide the 'head' of water, above the topmost part of the cooling system [the cylinder head]... The normal orifice for filling the mini radiator was sealed using a non-pressure cap...which has a solid rubber gasket inside. This because the radiator was on its side.... These are available from the usual go-faster sources. The Vitesse system radiator has no redundant filler orifice [hole, or whatever its called?]... Show's Triumph didn't go for ''make do & mend' design? My Mustang has it's overflow leading to a sort-of expansion bottle...put in by me [with some help from Bogg Brothers, East Lutton]...fed by the radiator overflow, into the bottom.....and an off-centre, badly drilled wee hole in the bottle's cap, to let air out, mainly. The Mustangs of the era [like other Fords] were prone to chucking their coolant out all over the road when overly hot. No thought given in those days to catching the stuff... The Dellow's radiator is a huge affair [for the engine size], with a massive top tank [intended for thermo syphon cooling originally]...but US race car regulations demanded a 'catch' tank, so it has a small catch tank at the end of the overflow pipe. This ought to be kept half full....I suppose it might act as an expansion tank? Both the Mustang, and the Dellow radiators are not filled right to the top, but merely [to half quote Ford] just covering the gills inside. However, the Mustang does seem to top itself up after a run....I presume that's why the water level in the ''expansion'' bottle drops over time? The Dellow doesn't seem to need topping up.......[good job I'm not on a water meter!] Edited May 31, 2023 by alastairq 5 Link to post Share on other sites More sharing options...
pH Posted June 2, 2023 Share Posted June 2, 2023 Two big old boats parked outside a house on our block: 13 1 Link to post Share on other sites More sharing options...
alastairq Posted June 2, 2023 Share Posted June 2, 2023 Those Americans certainly know how to keep the rest of the world at arm's length! :) 6 Link to post Share on other sites More sharing options...
RMweb Gold Dunsignalling Posted June 2, 2023 RMweb Gold Share Posted June 2, 2023 33 minutes ago, alastairq said: Those Americans certainly know how to keep the rest of the world at arm's length! :) From the length and width of the bonnet, it looks like a mechanic would have to get in with the V8 in order to work on it.... 2 2 1 Link to post Share on other sites More sharing options...
billy_anorak59 Posted June 2, 2023 Share Posted June 2, 2023 Me again... Sorry about the delay @alastairq – I was offline yesterday, so have only just seen your reply. Many thanks for your extensive reply – much appreciated, and thank you for taking the time, it helped. Looking again at the photos I have of the engine ‘as received’ (they were taken 30 years or so ago), and from your reply I thought that this is an expansion tank setup, and not a header. However, when taking another look, I am more confused than ever, as it could be acting as a joint header/expansion! (?) It seems to be both at the same time! This photo shows that the radiator in effect has two top hoses leading from it – one to the thermostat housing as per normal, the other leads to the expansion tank. Alongside it is a thinner (part metal)‘overflow’ pipe leading to the ‘high’ end of the expansion tank, and the expansion tank has an overflow pipe dumping to ground as would a radiator overflow. It certainly does not look standard, but I guess it worked. I've labelled the photo for clarity. When I rebuilt the engine, I replaced the components as you see in the photo, and the only thing that I am likely to have got wrong would have been putting the pressure cap that would have been on the radiator, on the expansion tank, and vice-versa. I’m still trying to work out how the expansion tank might have collapsed under vacuum if I had got that wrong though. Looking at the pressure cap ratings might be key, but I would have thought that the expansion tank overflow would have prevented a vacuum forming anyway? Doesn't look at all like the 'specimin' photo setup I posted earlier, so all a bit bizarre. Thanks again. 5 Link to post Share on other sites More sharing options...
RMweb Gold Dunsignalling Posted June 2, 2023 RMweb Gold Share Posted June 2, 2023 (edited) What you have, is two header tanks. The diagram posted earlier shows the Vitesse radiator not to have one, hence the remote header fitted to the top of the engine (confirmed with a pal who ran one for several years). The arrangement was presumably dictated by a need to ensure the pressure cap would be located at the highest point in the system, which is necessary to avoid air-locks occurring (especially in the heater, which tends to be the next highest point). Your radiator must originally have come from something other than a Vitesse (even if it was fitted to one when you acquired the components) and the header tank thereon is (or should be) effectively redundant. The higher rated of the two caps (or a non-opening one) should therefore go on the radiator to permit the uppermost one on the remote header to function as intended. Any topping up should take place via the cap on the remote tank. John Edited June 2, 2023 by Dunsignalling 1 3 Link to post Share on other sites More sharing options...
billy_anorak59 Posted June 2, 2023 Share Posted June 2, 2023 (edited) John - many thanks for this, it explains a lot, including why it was done. A remote header to avoid air-locks would be very plausible due to the lower bonnet line and differently positioned heater. As I said earlier, I suspect I got the caps the wrong way round. Schoolboy error. 19 minutes ago, Dunsignalling said: Quote The higher rated of the two caps (or a non-opening one) should therefore go on the radiator to permit the uppermost one on the remote header to function as intended. Any topping up should take place via the cap on the remote tank. Nicely explained and with a solution too! I'll take that - much appreciated. 👍 Edited June 2, 2023 by billy_anorak59 Bit missing 3 Link to post Share on other sites More sharing options...
Erichill16 Posted June 2, 2023 Share Posted June 2, 2023 Havent seen one of these for ages. P100? 9 Link to post Share on other sites More sharing options...
alastairq Posted June 2, 2023 Share Posted June 2, 2023 Replace the cap on the radiator with a non-pressure {blanking] cap....[as I hinted above?] https://www.rc-supplies.co.uk/standard-stainless-steel-non-pressurised-cap Link is just an example...others available via eBay. 3 Link to post Share on other sites More sharing options...
billy_anorak59 Posted June 2, 2023 Share Posted June 2, 2023 2 hours ago, alastairq said: Replace the cap on the radiator with a non-pressure {blanking] cap....[as I hinted above?] https://www.rc-supplies.co.uk/standard-stainless-steel-non-pressurised-cap Will do! Thanks for the link - cheers. 1 Link to post Share on other sites More sharing options...
RMweb Premium PhilJ W Posted June 2, 2023 RMweb Premium Share Posted June 2, 2023 6 hours ago, Erichill16 said: Havent seen one of these for ages. P100? They were favourites of cigarette smugglers and many were crushed by Customs and Excise. 2 Link to post Share on other sites More sharing options...
britishcolumbian Posted June 2, 2023 Share Posted June 2, 2023 On 11/05/2023 at 18:13, davknigh said: Ah yes, the big V8s. You could see the needle on the gas gauge fall as you stepped on the accelerator. But then gas was $0.32 a gallon… Cheers, David When I was a kid my great uncle had a Chevrolet Kingswood Estate, I swear it was bigger in the back than my room at the time was... we'd have four-five kids in there and have plenty of room... according to my dad it had the 454 engine and a 25 (imperial!) gallon fuel tank and it needed filling daily... 1 1 Link to post Share on other sites More sharing options...
TT-Pete Posted June 2, 2023 Share Posted June 2, 2023 My Merc amd my mate's Rover P6 parked at Hardingham station for the Mid Norfolk Railway vintage Bus rally on 14th May: Photos from the event at: and 11 Link to post Share on other sites More sharing options...
RMweb Gold Dunsignalling Posted June 3, 2023 RMweb Gold Share Posted June 3, 2023 (edited) 9 hours ago, PhilJ W said: They were favourites of cigarette smugglers and many were crushed by Customs and Excise. Hairdresser's truck! Strictly for on-road leisure purposes only. Any that were actually used as pick-ups by builders or farmers rotted out or fell apart (usually both) quite rapidly. It was unusual round here to see one still on the road by the time it was five years old.... It certainly never constituted any kind of competition for the Toyota Hilux! I did see one of the later ones with the Sierra bonnet a while back, but I doubt any survivors have ever done any serious work. John Edited June 3, 2023 by Dunsignalling 2 Link to post Share on other sites More sharing options...
KeithMacdonald Posted June 3, 2023 Share Posted June 3, 2023 14 hours ago, PhilJ W said: They were favourites of cigarette smugglers and many were crushed by Customs and Excise. Strange. Wouldn't a plain ordinary Ford Transit be less conspicuous? Just asking, just in case any of you lot are thus inclined ;-) 1 Link to post Share on other sites More sharing options...
peanuts Posted June 3, 2023 Share Posted June 3, 2023 5 hours ago, Dunsignalling said: Hairdresser's truck! Strictly for on-road leisure purposes only. Any that were actually used as pick-ups by builders or farmers rotted out or fell apart (usually both) quite rapidly. It was unusual round here to see one still on the road by the time it was five years old.... It certainly never constituted any kind of competition for the Toyota Hilux! I did see one of the later ones with the Sierra bonnet a while back, but I doubt any survivors have ever done any serious work. John there were a couple of the sierra fronted ones local to us that gained cosworth running gear one with a funky bodykit and another that was just a plain sleeper surprised a few of the local boy racers away from the lights till they cottoned on 2 1 Link to post Share on other sites More sharing options...
steve1 Posted June 3, 2023 Share Posted June 3, 2023 Today in the car park at Hull show. steve 9 Link to post Share on other sites More sharing options...
Hobby Posted June 3, 2023 Share Posted June 3, 2023 Got two of them!! 3 1 Link to post Share on other sites More sharing options...
RMweb Gold Oldddudders Posted June 3, 2023 RMweb Gold Share Posted June 3, 2023 3 hours ago, Hobby said: Got two of them!! Never mind, eh? 1 4 Link to post Share on other sites More sharing options...
RMweb Premium PhilJ W Posted June 3, 2023 RMweb Premium Share Posted June 3, 2023 10 hours ago, KeithMacdonald said: Strange. Wouldn't a plain ordinary Ford Transit be less conspicuous? Just asking, just in case any of you lot are thus inclined ;-) Almost every Transit van was stopped at one time by customs who soon cottoned on to the P100's. 1 2 Link to post Share on other sites More sharing options...
Rugd1022 Posted June 4, 2023 Share Posted June 4, 2023 Some tasty gems from 'Viva Italia' at Sywell aerodrome today... 17 1 Link to post Share on other sites More sharing options...
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