Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 M3W cooling fan amp draw.

Fuel supply system issues will not show any error codes on Protune.

Have you upgraded the fuel pump to a Walbro...as the fuel pump could be providing less pressure once warmed up..?

What amp alternator does the S&S 2.0L use?

I have an '05 CVO Harley Softail "B" motor and it uses the same 4-bolt pattern on the primary side and also has the same left side crank that the S&S uses. In my case I was able to purchase on eBay, a 50 amp upgrade from a Harley touring model and it all fit right in.

If you're a bit low on amps provided by your S&S alternator, you might look into the upgrade to see if it will help you out.

Dan

Setting the odometer display to volts would show if the alternator is a problem. Should be steady at about 14.4V

I do have a steady voltage reading at around 14 volts. I have checked that in the past.

Interesting thought about the fuel pump. Maybe I’ve got a bad one. I’ll put that on my list to replace.

Keep those ideas coming.

Thanks.

As others have suggested, with occasional rough running I would be suspicious of the ignition leads/plugs...at the very least, I would start with new high grade ignition leads (Magnecor have a good rep) and appropriate NKG Iridium plugs.

We had a period of intermittent rough running esp on long hot runs that was only finally quelled by changing out plugs/leads.

If you do/have done this then there is a firm base to go from...

Thanks JMD.

I just ordered a set of red Magnecor KV85 Competition spark plug wires.

Will also install the NGK dcpr7eix iridium plugs.

If it is as simple as changing the spark plug wires that would be great.

Good Luck!...at least making my suggestion prompted me to order some new plugs and a spare set of leads....!!

And if the spark plugs have the removable nipples...remember to nip them up tight with pliers. That's probably the most common cause of misfires on the M3W.

Keep us Posted please. Also, RedThree has a good point.

If it still possible to get the plug wire ends that slide onto the threaded portion of the plug after removing the smooth nipple top?

Good point Calum. I have been aware of the problem with loose terminals and those buggers in plugs without fixed terminals definitely do loosen. In my case this isn’t the problem because my current plugs have fixed terminals.

Stephen I’m personally not aware of plug wires that fit directly to the threads. I’ll definitely report what happens.

I’m going to go through my entire ignition system. I just was reading one of our old threads about spark plugs back in 2016. I reported back then how my engine smoothness was transformed by installing the NGK DCPR7EIX iridium plugs which at the time made me wonder if my coil was bad. This plug requires less voltage to make a good spark and would improve the situation if the coil is subpar. I don’t think the improvement was due to just installing a new plug because I tried other brands of new standard plugs without effect. However after awhile still seemed to experience similar symptoms so went back to standard plugs. I’m going to replace my coil as well and just ordered one. I’ve been reading about heat and coils. Not a good mix. Anybody have any thoughts about the placement of the coil right next to the very hot oil reservoir.

I believe my alternator and rectifier are functioning ok because my voltmeter reads a steady slightly greater than 14 volts under load. Will check to make sure all the electrical connections are intact.

Is there any other ignition component between the ECU and the coil?

Regarding the fuel system, I ordered a new fuel filter and will replace that. I don’t think this has been the problem though because these issues have been present from new. I’m going to leave the fuel pump alone for now pending results from these other steps. If working with the ignition side of things doesn’t help will then start looking more carefully at the fuel supply side including pump and injectors. I’m trying to do the simpler things I can do first and will reach out to professional assistance again if needed. I assume the ECU monitors all the engine sensors and reports a malfunction of any of these.

Really appreciate everyone’s input. Like I’ve said before the support we get from this forum is invaluable and greatly adds to M3W ownership.