Terry Field Posted March 7, 2015 Share Posted March 7, 2015 Put the 7 to bed properly last November, with a teaspoon of oil in the bores, but now I cannot even get it to fire, let alone start.Battery is fully charged and engine turns over at a good rate.Plugs properly gapped and good spark on all 4Dizzy cap clean in and outFresh fuel (I drained off about 1/2 pint from the carb feed to make sure the old stuff was out of the llines). Mechanical fuel pump is pumping OKBut still not even a hint of it firing - any clues as to where to go next? Terry Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 7, 2015 Member Share Posted March 7, 2015 Hmmm...Is that test of the spark by watching it jump to the block?Is the fuel getting to the plugs? What do they look like after a long attempt?Recheck that the right lead goes to the right plug?Blast of Easy Start or similar?Jonathan Link to comment Share on other sites More sharing options...
SM25T Posted March 7, 2015 Share Posted March 7, 2015 Ask Baz ... he knows how to make a fire in a crossflow ! Link to comment Share on other sites More sharing options...
Terry Field Posted March 7, 2015 Author Share Posted March 7, 2015 Hi Jonathon,I checked the spark across the plug electrode by earthing it against the block - didn't try to jump the spark from the plug to the blockPlugs seem to be getting wet, although I haven't gone so far as to strip the Webers to check the floats.Leads definitely on the right plugs.Never used Easy Start, but it mght be an optionTerry Link to comment Share on other sites More sharing options...
OliverSedlacek Posted March 7, 2015 Share Posted March 7, 2015 How many pumps are you giving it on the accelerator (and are the accelerator pumps working). If it hasn't run for ages, I'd give it 10 pumps and then churn it with the throttle open just a crack. That way you start out with too much fuel, but it gets sucked through. Hopefully the engine will catch as the mixture drops to the correct level.Easi-start is a great diagnostic, because it makes the engine start then you know to focus on fueling. Link to comment Share on other sites More sharing options...
Drumster Posted March 7, 2015 Share Posted March 7, 2015 Hi Terry,When I put the Zetec in and used the Webers initially I had real trouble getting the engine to fire and, although being a brand new engine it was quite tight, a major part of the problem was that the floats had become stuck and hence it was over-fuelling and fouling the plugs. Link to comment Share on other sites More sharing options...
Terry Field Posted March 7, 2015 Author Share Posted March 7, 2015 Hi OliverThat's just about what I am doing, and always do after a longish lay up, always successfully. But this time I can't event get it to catch once. Hi Chris, Good to hear from you. The floats are the only thing left to check, but I think I will give the easy start a try (should be OK using it with Webers?) before stripping the carbs and probably having to invest in a new set of gaskets!CheersTerry Link to comment Share on other sites More sharing options...
Molecular--Bob Posted March 8, 2015 Share Posted March 8, 2015 You may have fouled your plugs with the oil you put in. Try new plugs before you take it all apart. Link to comment Share on other sites More sharing options...
scorcher Posted March 9, 2015 Share Posted March 9, 2015 I'm also having grief with my Crossflow after its winter hibernation. No fuel is getting to the Webers despite vigorous throttle pumping. As mentioned above perhaps the floats are stuck so is there a trick to freeing these without taking stuff apart with the danger of knackering the gasket/s ? Failing my suspicions what else might be stopping the fuel getting to the carbs ? tank is 3/4 full ! Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 I tried the Easy Start Route and it fired straight away but only until the Easy Start was burnt up, then it just churned over again. So based on that I am ruling out ignition problems.Took the tops of the carbs. The floats all seem to be moving freely and the float chambers were about half full once I had removed the floats. Also checked the filters and jets for any foreign bodies.So I am now just about at the end of my technical knowledge / competence!I could call out Home Start, but I'm just a bit concerned that I won't get a 'proper' mechanic, but just a trailer man who will want to take it to the nearest garage!At least it's raining at the moment!Scorcher, are you using a mechanical or electric fuel pump?Terry Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 9, 2015 Member Share Posted March 9, 2015 I'm not an expert on these carburettors but after that experiment I'd now move to OliverSedlacek's strategy above: overfuel and hope it catches as you come back from being too rich.if that doesn't work after a couple of attempts I'd inspect the plugs after the pumping bit.Do you have a big battery/ jump leads/ power pack close to hand?Jonathan Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 Jonathon, Thanks, but I have been through that scenario several times over the last week - it just churns until the battery goes flat, then the same process starts again with a fresh battery. I'm thinking carb issues, but don't know enough about it. Terry Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted March 9, 2015 Member Share Posted March 9, 2015 Where are you... and would you like a visitor... there are some very helpful members out there...Jonathan Link to comment Share on other sites More sharing options...
scorcher Posted March 9, 2015 Share Posted March 9, 2015 Mechanical pump Terry. I will have another look at the problem tomorrow when the weather is kinder - good luck to you as well ! Pressure building as the MOT is booked for this Friday. Link to comment Share on other sites More sharing options...
andy couchman Posted March 9, 2015 Share Posted March 9, 2015 Mechanical pump has a lot to do to so will need a lot of (low speed) churning to get fuel through. Maybe take the plugs out and churn it over on the starter until fuel comes out the pipe?Alternatively can you dripo fuel into the flat chambers in some way?Good luck!Andy Link to comment Share on other sites More sharing options...
elie boone Posted March 9, 2015 Share Posted March 9, 2015 If it fired on start pilot it would be enough for the mechanical fuel pump to fill the chambers.So other you have a blokked fuel line or a hairline crack in the fuel line so that the fuel pump draws some air Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 Jonathon,I am just outside Wellington / Taunton area. You are welcome any time CheersTerry Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 Just to clarify, the fuel is pumping through from the pump without any problem. Terry Link to comment Share on other sites More sharing options...
Klunk Posted March 9, 2015 Share Posted March 9, 2015 Hi Terry,How much old fuel did you have in the tank before you added the new fuel? If you've added the new fuel to a non empty tank, the 1/2 pint will not be enough to guarantee fresh fuel. To prove this, take the tops off the carbs, remove fuel, pour new fuel into chambers and replace tops. If it wont then fire this removes the fuel from the equation. I had exactly the same issue with my crossflow and it only started once I'd drained the tank and put in fresh fuel. I didn't believe it would be the problem but it was.Also, what plugs are you running? What spec is the engine?Regards,Giles Link to comment Share on other sites More sharing options...
Klunk Posted March 9, 2015 Share Posted March 9, 2015 Found my thread hereGiles Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 GilesI put in 10 litres to an almost empty tank. Spec is a 1700 145 bhp with BP7ES plugs - same as it has been for the last 12 years!I will try your fuel in the carbs trick though. Thanks Terry Link to comment Share on other sites More sharing options...
Klunk Posted March 9, 2015 Share Posted March 9, 2015 Sorry Terry, was just trying to gauge it against my old engine Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 No problem! There is no such thing as a silly question Terry Link to comment Share on other sites More sharing options...
OliverSedlacek Posted March 9, 2015 Share Posted March 9, 2015 The evidence seems convincing that fuel is getting to the carbs if it's coming out of the feed to the carbs and the plugs are getting wet. I'm also assuming you haven't got the HT leads swapped, right?One thing you could try is 10 pumps and then try starting it on full throttle. If it fires on full throttle, I'd look for air leaks. Link to comment Share on other sites More sharing options...
Terry Field Posted March 9, 2015 Author Share Posted March 9, 2015 Evening Oliver,Fuel is certainly getting to the carbs.HT leads are all ok (fully numbered and not changed since lay up)Could be an air leak, but why would that appear if nothing has been disturbed during the lay up, and I would expect it to fire even if it didn't run.I need to check whether the plugs are getting wet - I may have been over optimistic on that view, so I need to check that again. If my original thought was wrong, which I think it might have been, I have worked my way round to a problem with the transfer of fuel from the carb reservoirs to the plugs.You mentioned the accelerator pumps, but I am not sure how to dismantle those and to check them. There seems to be a form of clip or plate holding them in, but again I am not sure how to remove them. Wouldn't it at least fire if one of them was working?So, in summary, there seem to be two things left, stale fuel or the accelerator pumps. I'll try pouring fresh fuel straight into the reservoirs, but I will need some guidance on the pumps.Thanks for your interestTerry Link to comment Share on other sites More sharing options...
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