Sootysevener Posted June 23, 2005 Share Posted June 23, 2005 I'm getting a lot of liquid flow into the catch tank. I know it expands as it gets hot but the stat is 88 degrees and works well though there is some temperature uplift in traffic to 95 deg when the fan stat kicks in. Just wondering whether the rad cap needs replacing and if so what pressure. Stant caps listed on Mocal website at 19/20, 22/24 and 29/31. Which is best for 1700 XF? Advice please - cannot find anything relevant in the archives David 1989 1700XF SS with upgraditis Link to comment Share on other sites More sharing options...
Myles Posted June 23, 2005 Share Posted June 23, 2005 'm getting a lot of liquid flow into the catch tank Whaddya mean? By 'catch' do you mean 'expansion'? What do you mean by 'flow'? Can you see a jet of coolant passing into the tank, does the level remain mainly-constant or rise??? Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
Sootysevener Posted June 23, 2005 Author Share Posted June 23, 2005 Myles Fill the rad above the level of the stat and empty the overflow catch tank ( like a Unipart washer bottle) - not a header tank. Run the car for say 25 miles and i've got about a third of a litre of water/AF in the overflow tank again - boring as this leaves the rad not full when cold and leaves me concerned about localised hot spots in the cooling system David 1989 1700XF SS with upgraditis Link to comment Share on other sites More sharing options...
grumpy the 7th Posted June 24, 2005 Share Posted June 24, 2005 I don't follow the cooling system is presurised when hot so shouldn't have a catch tank. As Myles says it should have an expansion tank. Do you have any piccies of the bits discribed?? rog C7 TNT - it's like dynamite (Honda Irish Green and Peugeot Graphite grey ) Link to comment Share on other sites More sharing options...
Nigel Riches Posted June 24, 2005 Share Posted June 24, 2005 Hi David, I think what you're describing is the normal behaviour, but your rad cap may be duff, if the expanded coolant flows into the bottle when the engine is hot it should then be drawn back into the system as the engine cools. The rad cap ( fitted on the thermostat housing )should be a two way type, and the pipe from the filler neck too the expansion bottle should reach too almost the bottom of the bottle, there should always be a level of coolant, say 1/3 full in the expansion bottle, cos if the pipes in the air, the air will be drawn into the engine, not good, as you know. My Caterham supplied cap has a part no. 1613292, (circa 1995 )but is actually a Ford item, as I went from the original non sealed system to a sealed one for the very reasons you mention, air in the cylinder head, I could flick a picture of mine if it's any help, e-mail me direct and I'll get on it this weekend. Regards Nigel. 1982. 5 speed, clamshells. B.R.G / Ali. The True Colours. Link to comment Share on other sites More sharing options...
nickdodo Posted December 31, 2005 Share Posted December 31, 2005 Did you ever get this sorted out... I have made a mod to my X flow so that I don't get this problem. Nick Nick in the (1987) 1700 X Flow... Link to comment Share on other sites More sharing options...
Sootysevener Posted December 31, 2005 Author Share Posted December 31, 2005 Not sure Nick - been re wiring, re flooring and carbonising with new instrumentation since Autumn but I put a new Stant racing cap on and relocated the catch tank. Bigger problem now is getting all the jobs finished - where does the time go? 😬 David 1989 1700XF SS clams with carbon Link to comment Share on other sites More sharing options...
Normans_Ghost Posted January 1, 2006 Share Posted January 1, 2006 David, I know it's late on this but it sounds like you have a non-sealed system. The catch tank is just that a tank to catch the coolant that will come out of the engine when it expands. Tha normal radiator level is about 1" from the top when cold. To make a sealed unit you need to replace the sprung rad cap with a non-pressurised one - it's flat in the underside. Then replace the thin overflow pipe with a thicker pipe and take it to an expansion bottle (Ask Darren at Caterham and explain you want the bits to convert from open to sealed cooling system). I prefer to have the expansion tank above the cylinder head level but in theory it doesent matter. Therefore you can site it on the bulkhead or by the x brace behind the rad. The advantages of the sealed system is that all the air is expelled from to engine coolant therefore reducing corrosion and the coolant capacity styas constant. Many will claim there are many other advantages but I think that's all there is. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Guy Lowe Posted June 3, 2006 Share Posted June 3, 2006 David Did you ever identify what the cap was, mine is doing the same and I need to replace it Guy From Clam shells to Cycle wings for only 3K here IT'S MANGO AND THAT'S THE END OF THE MATTER Link to comment Share on other sites More sharing options...
Normans_Ghost Posted June 3, 2006 Share Posted June 3, 2006 Guy, If it's a pressure cap it should have a poundage on it. Halfords should have one. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Guy Lowe Posted June 3, 2006 Share Posted June 3, 2006 No that's the problem Norman, it looks like a "standard" cap but doesn't have a pressure rating. Can a kind X Flow owner have a look at theirs and tell me what the release pressure is please? Guy From Clam shells to Cycle wings for only 3K here IT'S MANGO AND THAT'S THE END OF THE MATTER Link to comment Share on other sites More sharing options...
Normans_Ghost Posted June 3, 2006 Share Posted June 3, 2006 Guy,if no one comes forward then play safe with 7ln or go for 15lb. If you fit the higher then check for leaks on all hoses. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Sootysevener Posted June 3, 2006 Author Share Posted June 3, 2006 Guy I got a 22lb Stant racing cap from Burtons. Had a bit of seepage from the top hose at the rad end but removed the silicone hose, wrapped the rad outlet in plumbers PTFE tape about 8/10 times and refitted the hose - et voila!. Care not to over tighten the jubilee clip as its easy to crush the outlet pipe from the rad and then you'll definitely get leaks. I still get expansion into the top tank but this is inevitable as the water expands. with a prper sized hole in the tank bung just big enough to take the pipe i simply refill the rad with the expanded water taking care to ensure i don't return silt to the system. Over the last 4 months I've only added it back a couple of times and the overflow is clean and largely free of silt David 1989 1700XF SS clams with carbon webshots here Link to comment Share on other sites More sharing options...
Normans_Ghost Posted June 3, 2006 Share Posted June 3, 2006 David, 22lb is a bit high for a standard road car. It doesn't need to be that high. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Guy Lowe Posted June 3, 2006 Share Posted June 3, 2006 Norman Just been to Halfords and got the cap recommended for the RWD 1600 Escort/Cortina and it's rates at 13LBS. Just got to wait for the car to cool down now, Halfords is only 2 miles away but it took me an hour and I did 40 miles 😬 Guy From Clam shells to Cycle wings for only 3K here IT'S MANGO AND THAT'S THE END OF THE MATTER Link to comment Share on other sites More sharing options...
Normans_Ghost Posted June 3, 2006 Share Posted June 3, 2006 Funny that, I was sent to the village (1 mile) to get a bread. Took me 1.5 hours and 40 miles. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Guy Lowe Posted June 3, 2006 Share Posted June 3, 2006 😬 From Clam shells to Cycle wings for only 3K here IT'S MANGO AND THAT'S THE END OF THE MATTER Link to comment Share on other sites More sharing options...
Sootysevener Posted June 4, 2006 Author Share Posted June 4, 2006 You lucky boys - all the way around Guernsey is only 24 miles with a 35mph limit! David 1989 1700XF SS clams with carbon webshots here Link to comment Share on other sites More sharing options...
JKJ Posted June 4, 2006 Share Posted June 4, 2006 If it's a 1700SS then you have the wrong ' stat fitted, it should be 74°C. I've just finally cured my overheating problems on my car, regularly spitting out it's coolant into the expansion bottle, and road. It turned out that the pressure cap was U/S, simple really. I guess it was overheating at the start due to the wrong pressure in the system, then not sucking it back into the engine due to the lack of vacuum, due to the leaking cap. New cap, bleed system, at the radiator, new 74°C stat, unnecessary, but I now have 2 spares, and it's back to normal running temps. Link to comment Share on other sites More sharing options...
JKJ Posted June 4, 2006 Share Posted June 4, 2006 Sorry, should have said, get your cap from Redline, or give them a ring and they will probably give you the part number, always had excellant service from them. Link to comment Share on other sites More sharing options...
Guy Lowe Posted June 5, 2006 Share Posted June 5, 2006 JKJ mine was not overheating like Sootysevener's just letting water through the cap at normal running temp. Have now fitted a new cap (1600 OHV Cortina) and the problems solved. Agree about REDLINE use them all the time, just wanted the car sorted to go to Goodwood Sunday. Guy From Clam shells to Cycle wings for only 3K here IT'S MANGO AND THAT'S THE END OF THE MATTER Edited by - Guy Lowe on 5 Jun 2006 10:06:24 Link to comment Share on other sites More sharing options...
susser Posted June 5, 2006 Share Posted June 5, 2006 A pressurised cap will protect a system fom local overheating; For instance, a 13psi cap will raise the boiling point of the system to 115-120 deg C, depending on the properties of the coolant. I believe an unpressurised system, whilst it reduces stresses on hoses, actually makes the system more prone to failure. this could be a boil up, ejecting steam and boiling water, or local steam pockets leading to local overheating (in the head for example). I'm not even going to mention "air" 8u66er Link to comment Share on other sites More sharing options...
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