Non Starting P1800

[jimmyjam]

Hello,
Was wondering if ANYONE could help me in my frustrating problem with my now non starting Volvo P1800 1964 B18 Twin carb.

The car just wont start. The engine cranks but it just dont fire up. The last thing I did to the car was it was running and managed to idle quite well. A few days later got into the car and now it just turns but does not start. There is petrol in the tank, there is spark from the spark plugs ( although not a really strong blue spark more of a yellowish spark), I have undone the coil HT lead rest it in a good earth and that also has a spark. I have checked inside the distributor cap and all looks fine with no corrossion. The sparks are new, although a little black I have cleaned them. ( the car has not been driven yet but only started outside my garage and has been mostly running on choke, hence the black). I have replaced the gaskets on the float cambers on the SU and replaced, also replaced the valve and seats for new ones.

Please please could you help me as I am worried it maybe something simple and dont want to get ripped of by a modern mechanic who has no idea what he is doing.

Your time much appreciated.

Jimmy Nicola UK

jimmynicola@hotmail.com

[Stuart Read]

Hi Jimmy

You say there's petrol in the tank - but is there any in the carburettors? This may sound obvious but if the drainage hole in the filler recess has become blocked, what you may actually have is rainwater! Disconnect the feed pipe to the carburettors and see if what is being pumped through is actually petrol - assuming something is being pumped through and that you don't have a blockage further back!

All the best. . .

Stuart

[jimmyjam]

Thanks Stuart, yes there does not seem to be much petrol in the float chambers, and they do contain a fine red sedement. Would this also be in the hole inside the float chambers. What are those holes for. When I try to start the car there is always a strong smell of petrol at the carbs and its wet at the bottom of one of the float chambers. Appreciate your help...any more would be appreciated. Thanks Jimmy.

[mike gilbert]

Jimmy, there are only three things you need to get an engine running. Petrol getting through the carb into the manifold, a spark at the the plugs and the timing correctly set. But you also need enough juice in the battery to get the engine spinning fast for a good minute or so. Use jump leads from another car to give your battery a boost. Then Try starting it using a gravity fed remote tank piped to the carbs in place of the fuel line, something like the exansion tank from a radiator will do and use fresh petrol. With the air filters off and engine turning over you should be able to see the fine spray of petrol being sucked from the jet into the carb neck. If that is happening - and/or you can see the petrol level in your container dropping - fuel is not the issue. Then take out each spark plug in turn and check that it is sparking. If it is theres no need to worry about HT leads and dizzy caps because they must be working or the spark plugs wouldn't. If you have sparks and fuel then it has to be timing or a catastrophic loss of compression, which I very much doubt. Check the distributer pinch bolt is done up tightly. If not it could have moved and effected the timing. A couple of times in the past on B18's I've been stumped and put in new spark plugs as a desperation measure and it worked immediatley both times - dont ask me why. By the way I have the seat adjuster knob you are looking for but the shaft it attaches to is broken. If you still want it you can have it.
Mike.

[jimmyjam]

Dear Mike, Thanks for the helpful reply. I have tried all things today including cleaning all leads, cleaning sparks, cleaning inside dis cap. What I found today was that I think 3 of the sparks are not sparking. For instance, When I took out spark plug 1 the engine was trying to start, when put back in only cranking was happening. There is definately fuel getting to the carbs, because there is always a fuel smell around the carb area after trying to start. Mind you I think the levels in the float chambers were quite low. (maybe).

I would be interested in the black knob you mentioned and bung in the bar if you want. Where are you based Mike.
Kind Regards...Jimmy