Rootes75 Posted October 19, 2020 Share Posted October 19, 2020 We are having issues with our Commer truck, issues in her not starting. She has a 6 cylinder sidevalve petrol engine with the Solex 40 FAIE carb. We have set the timing, checked all gaps and plugs for sparks, all fine. We found the manifold gasket was leaking so thats been replaced. Next we fitted new fuel lines and cleaned down the carb, we have checked and she is getting a good fuel supply. We have also checked the compression which is good. So, with a good strong battery she turns over lovely, but thats about it. Once in a while she does fire/engage but never actually starts. She then just floods everytime. It you put her on full choke she tries hard to fire and almost gets there but floods very quickly. Even a shot of easy start didnt do anything. We are ticking off things to try out but seem now to be going round in circles. Any suggestions, no matter how simple, anything could help. Quote Link to comment Share on other sites More sharing options...
earlymb Posted October 19, 2020 Share Posted October 19, 2020 It's either fuel or spark I think... Remove one of the spark plugs, hold the thread against the block or any other mass and see if it sparks when the engine turns over? What is the condition of distributor cap and leads? Quote Link to comment Share on other sites More sharing options...
David Herbert Posted October 19, 2020 Share Posted October 19, 2020 If you have fuel (or easy-start) getting to the cylinders and compression it must be ignition. If you have a good strong spark at the plugs then it has to be timing. Are you certain that it is sparking at the top of the compression stroke and not the exhaust stroke and that the plug leads are in the right order on the distributor, not the reverse order. Both mistakes are very easy to do ! You have mentioned flooding. I presume that you are happy that the float valve is doing its job ? David Quote Link to comment Share on other sites More sharing options...
Rootes75 Posted October 19, 2020 Author Share Posted October 19, 2020 4 minutes ago, earlymb said: It's either fuel or spark I think... Remove one of the spark plugs, hold the thread against the block or any other mass and see if it sparks when the engine turns over? What is the condition of distributor cap and leads? The plug leads are all new and so are the contacts. We have checked and she does get a spark at the lead ends. Quote Link to comment Share on other sites More sharing options...
earlymb Posted October 19, 2020 Share Posted October 19, 2020 Distribution cap has no cracks and the small graphite piece (don't know the proper name) is present? Any chance you can borrow another carb from a running engine to swap and try? Quote Link to comment Share on other sites More sharing options...
Rootes75 Posted October 19, 2020 Author Share Posted October 19, 2020 3 minutes ago, David Herbert said: If you have fuel (or easy-start) getting to the cylinders and compression it must be ignition. If you have a good strong spark at the plugs then it has to be timing. Are you certain that it is sparking at the top of the compression stroke and not the exhaust stroke and that the plug leads are in the right order on the distributor, not the reverse order. Both mistakes are very easy to do ! You have mentioned flooding. I presume that you are happy that the float valve is doing its job ? David Thanks David. We have checked and double checked the firing order against the plug leads and she is right. I know what you mean though in making a simple mistake in the order. When we checked for the spark from the lead against the head with a screwdriver I was a bit concerned that the spark was weak. In our experience with our other Commer even with the timing out she will still fire and start but just run very poorly (we have sorted her timong out). This Commer simply wont actually fire up. Quote Link to comment Share on other sites More sharing options...
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