Crosflow powered 7 - won't start
Discussion
Xflow engines can be a bit finicky. Weber carbs can also be a touch temperamental too. Keep on top of both and they will be fine though.
Mine has the choke connected but it pointless using it, it just doesn't need it.
I would check for a spark as mentioned, cable tie the plug to something metal and spin it over. Also check for fuel at the carbs. With the pump primed and filters off, look down the trumpet and open the throttle. You should see a blob of fuel(technical term) fall into the carb. If this doesn't happen then pull of the fuel feed pipe and put it into a bottle as mentioned before, ignition on and it should pump fuel at a decent rate into the bottle.
Xflows are very easy to work on and to diagnose problems, they are probably the most simple of engines to learn/work on.
If anyone has worked out how to stop them leaking oil though, I'm all ears!
Mine has the choke connected but it pointless using it, it just doesn't need it.
I would check for a spark as mentioned, cable tie the plug to something metal and spin it over. Also check for fuel at the carbs. With the pump primed and filters off, look down the trumpet and open the throttle. You should see a blob of fuel(technical term) fall into the carb. If this doesn't happen then pull of the fuel feed pipe and put it into a bottle as mentioned before, ignition on and it should pump fuel at a decent rate into the bottle.
Xflows are very easy to work on and to diagnose problems, they are probably the most simple of engines to learn/work on.
If anyone has worked out how to stop them leaking oil though, I'm all ears!
Does it have an electric fuel pump?
Certainly the fuel pump is mechanical. I guess there may be a lift pump which is electric to help get it from the tank.
Any progress OP? I'm agog to see what's wrong!
Certainly the fuel pump is mechanical. I guess there may be a lift pump which is electric to help get it from the tank.
Any progress OP? I'm agog to see what's wrong!
AdamIndy said:
ignition on and it should pump fuel at a decent rate into the bottle.
BertBert said:
Certainly the fuel pump is mechanical. I guess there may be a lift pump which is electric to help get it from the tank.
My old x/flow had a mechanical pump and it is very simple in design and operation. The pump is mounted on the side of the block and works from a cam off the camshaft. There is a lever in the pump that moves up and down to operate a diaphragm within the pump body to suck the fuel through from the tank and push it up to the carbs. So ignition on will not see any fuel coming out of the fuel line as suggested above
Aeroscreens said:
So ignition on will not see any fuel coming out of the fuel line as suggested above
But ignition on and cranking the engine over on the starter motor will, as I said in my post on Sunday (page 1 of this thread).I have known mechanical pumps fail during a winter lay-up, where there has been a small tear in the diaphragm or a crack in the lever that formed when the car last ran, but that has opened up because the engine came to rest with the finger on the peak of the cam.
Many thanks to Mike for popping over last night and checking out my car. We are pretty sure the fault has been identified - a broken distributor cap. So, a new cap and rotor arm will be on order today.
Thanks also to all who have suggested various theories over the past few fays
I'll let you know if and when everything is sorted.
GO PISTONHEADS.
Thanks also to all who have suggested various theories over the past few fays
I'll let you know if and when everything is sorted.
GO PISTONHEADS.
Eric, you have clearly been very investigative and have had lots of advice but could I suggest you go back to basics. Please first establish if you have fuel reaching the carb and that you have a spark. Lack of either or both will lead you to the next step.
Appreciate your arms are no longer that normal, but for under-bonnet diagnostics get hold of a jump-start lead. Remove all plugs. Connect one to a plug lead and rest the plug on the manifold or block. You can even hold it in place by the insulated connector -it won't kill you. Connect one end of the jump cable to the starter motor; switch on the ignition and then touch the other end of the jump lead to the battery. Let the engine turn over briefly to see if you have a spark....
As for the fuel, disconnect the pipe from the fuel pump or carb and, again, turn the engine over briefly to see if petrol comes out... .
Let us know the results.
Appreciate your arms are no longer that normal, but for under-bonnet diagnostics get hold of a jump-start lead. Remove all plugs. Connect one to a plug lead and rest the plug on the manifold or block. You can even hold it in place by the insulated connector -it won't kill you. Connect one end of the jump cable to the starter motor; switch on the ignition and then touch the other end of the jump lead to the battery. Let the engine turn over briefly to see if you have a spark....
As for the fuel, disconnect the pipe from the fuel pump or carb and, again, turn the engine over briefly to see if petrol comes out... .
Let us know the results.
what is all that about?
Take out a plug. Re-connect to plug lead. Rest it on a metal thing within sight. Crank the engine!
And as has been noticed, OP looks to be sorted. Although the suspicious amongst us are wondering how it ran before and when the disti cap broke! Waiting to hear a happy ending though!
Take out a plug. Re-connect to plug lead. Rest it on a metal thing within sight. Crank the engine!
And as has been noticed, OP looks to be sorted. Although the suspicious amongst us are wondering how it ran before and when the disti cap broke! Waiting to hear a happy ending though!
Chuggy said:
Appreciate your arms are no longer that normal, but for under-bonnet diagnostics get hold of a jump-start lead. Remove all plugs. Connect one to a plug lead and rest the plug on the manifold or block. You can even hold it in place by the insulated connector -it won't kill you. Connect one end of the jump cable to the starter motor; switch on the ignition and then touch the other end of the jump lead to the battery. Let the engine turn over briefly to see if you have a spark....
BertBert said:
Although the suspicious amongst us are wondering how it ran before and when the disti cap broke!
Again, I have known it happen. I once had one where the centre electrode broke off while a car was laid up, and I've certainly had them where a crack in the cap worsened while the car was standing (moisture getting in and freezing, possibly? Who knows?).Unless the crack is catastrophic, though, you usually get a misfire and rough running rather than a completely dead engine. Ditto with moisture on the cap causing 'tracking'.
The centre electrode in Eric's cap has eroded away completely, there was lots of carbon dust within the distributor and the rotor arm contact was completely blackened. I understand the engine had been running poorly before being laid up for the winter and now wont restart.
Although there may have been enough voltage arcing to the rotor arm to run a warm engine, albeit poorly, there is clearly not enough spark to light up a completely cold engine or even enough voltage to activate a spark tester.
Whether, once this is rectified other issues are evident, remains to be seen, but hopefully a cap and rotor arm change will restore the engine to health.
Although there may have been enough voltage arcing to the rotor arm to run a warm engine, albeit poorly, there is clearly not enough spark to light up a completely cold engine or even enough voltage to activate a spark tester.
Whether, once this is rectified other issues are evident, remains to be seen, but hopefully a cap and rotor arm change will restore the engine to health.
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