Wits End

[johnbirchjar]

Hi guys,I have a problem that is driving me nuts ,intermittent firing on one cylinder.(Allways the same one, N/Side)
Up to now I have re-newd all the "O"rings on both Carbs,I have put sealer where the Carb bolts to the Frame,had the offending Carb to bits and cleaned the Jets,toped up the dash pots,swapped over the Coils,changed the Plug,nothing seems to make any difference,the symptoms are these,cold engine, fire up on part Choke,fires up on one cylinder(Chamber)run at 2,000 rpm for about 30 secs,then reluctantly other chamber briefly stutters into life,then back to running on one chamber,persivering with one chamber results in the occasional loud bang and flames from the exhaust,(this is usualy a sign of a weak mixture?)I have tried richening the mixture and weakening the mixture,nothing seems to work,I have double checked the wires to the coil,Big fat spark at the Plug,I am truely at a loss,any ideas?a truly frustrated J.B.

[Anthony Duffield]

John,

I have had a similar problem of when cold the right hand side would not pick up until warmed up, I found the cold start jet (the arrangement that the choke cable is connected to) blocked with dirt, once cleaned out it now pickes up and runs well even when cold.

How many turns out from fully clockwise are the idle adjustment screws?

Tony

[steve traynor]

hi
if left on side stand maybe oil collects in chambers or ignition starting to play up

[barney]

John,

I don't know if this will help, but I've just been through a very frustrating period with my F1 Sport, when it would only run on one rotor.

I stripped and rebuilt the carbs twice. Replaced the coil, send the ECU back to Mini Mag for testing, and did every possible form of diagnosis known to man.

In a final act of desperation I stripped the carb again, to find the cold start mechanism wasn't returning properly on one carb. Once I fixed that, and the bike was back on both rotors and running better than ever.

I've developed a mantra when it comes to my F1 - It's always the carbs, it's always the carbs, it's always the carbs!!!

They're super awkward to work on a F1 Sport, but the only problems I have had in 10 years of ownership relate to dirt or wear in the carbs!!!!

Hope this helps.

Barney.

[johnbirchjar]

Hi Tony,To be honest I have no idea about the Idle screws,and the W/shop manuel gives no guidance at all,with the air cooled engine I think four 360o turns from fully closed seems to ring some sort of bell,but with the Commander engine? they don't seem to have any effect what so ever , but having said that I am having no end of grief trying to get the b*****y thing to run at all .
Most of the things the other guys have suggested on the Forum I have tried allready.
This morning I fitted an extra Earth Lead on the N/Side(as suggested by one Paul Ralf Esq:'cos the spark at the plug was running inside AND outside the plug)which may have been the cause of the N/Side intermittent firing,it seemed to work,but then the O/Side began exhibiting the same symptoms ,a quick change of Plug seems to have cured that(hopefully)but for how long is anybody's guess.
The Idle is all over the place so I am now off to try and sort that out,(I am not all that optimistic)I will report anon,J.B.

[tim harrison]

Hi John A fat spark doesn't always mean that the plugs are operating properly. A change is a simple task, Next borrow an electronic ignition box and try it, Ok so the ignition probably isn't the problem but once you have tried these two simple checks you can then concentrate on the carbs, If they are set as per the book then it should be a fastish idle. fine adjustment can then be made using the two idle screws. I assume that you have thoroughly cleaned the carbs. The only reason that I think that it could be ignition is because even when the carbs are a bit dirty or leaking slightly the Commander engine often runs ok above 3000 revs whereas the ignition is likely to be as bad at high revs. Tim

[johnbirchjar]

Hi Tim,What do you call a "Fastish Idle"? I have managed to get mine to idle at 1,000rpm(as opposed to the 800 on the air cooled engine) with only very slight "Hunting".(and no Hunting )
Went for a blast this morning,bike behaved quite well,except for the continuing problem of overheating ,even with a "Bellypan" auxiliary water tank containing 4ltrs + the 2ltrs in the Rad the bike still overheats if rode at anything over 65mph,most frustrating .I suppose the problem could be the "Sender" or the Temp Guage,but both are brand new,so rather unlikely.
I believe one of our club members has a brother who fitted a Commander engine in a Suzie? frame and used a "Davies Craig" electric water pump?(as have I)if he reads this on our Forum(or someone knows of him)can he inquire as to the model of his C/D pump? and how much water his bike has in it's system?(I believe Commanders have 5ltrs)
According to the Spec Sheet my pump "pumps" 4ltrs a minute,anybody any idea if this is enough?and if not,would another pump running in tandem pump 8ltrs?or do's it not quite work like that ,sorry if I seem a bit dim,but this is a completely new ball game for me ,rgds,J.B.

[tim harrison]

HI JB, the factory setting for the carburettors is designed to fast idle when the engine is running in, this clearly does not apply to your engine which should happily idle at 600 rpm. I can't assist with the electric waterpump. The standard version is mechanical and therefore speeds up as the engine runs faster. The running temperature is largely regulated by the operation of the fan. mine generally runs at 85/90 degrees but may creep up on very hot days or in heavy traffic/ If your pump is not circulating suffociently at higher speeds obviously overheating may occur. Regards. Tim

[Richard Negus]

John,
Just a few questions so I can understand what you've got:
.where did the Commander engine come from and do you know for a fact that it's in good condition
.what electric pump are you using? Manufacturer and model number?
.do have an electrical controller for the pump?
.have you taken the thermostat out and blocked the bypass passage?
.are you using the Commander radiator, modified, and the standard fan?
.are the carburettors overhauled and set to factory specification?
.does the engine have a thermistor or thermal switch?

That you can only get 2 litres of coolant into the system suggests a monster air-locksomewhere. With a typical size radiator, it should take around four litres. If the pump is up high, it may be air-locked and not able to pump water. Mine had a small air bleed pipe from the pump casing direct to the radiator.
The lack of a good idle is down to either a low-compression engine or incorrect carburettor setting.
How about photos of each side of the engine/radiator installation?
R.

[johnbirchjar]

Morning Richard,answers to your questions are as follows.
Engine acquired from fellow club member,one Dereck Fox Esq(Del Boy)106,000 miles,I heard it running,albeit not for long as the water pump had been removed for modification(still ongoing )I wasn't too worried as I had planed to fit an electric one anyway,and since I have had it running it sounds just fine,with plenty of Compression and no unusual rattles.
Water Pump is from an Australian Company,(Davies Craig and is their EPB Model,) and pumps out 4.5ltrs a minute.(any idea what the Commander pump out?)
No Thermal control switch,just on/off switch on the handlebars.
Thurmostat removed and housing left open.
New Radiator had to be custom made 'cos the Commander one was too wide to fit between the sub-frame on the Triumph Fairing,10mm off each side,hight and depth as per orriginal.
Carbs off the Classic.New "O" rings on every orifise,carbs striped and cleaned.
Is the Thermastor? the little one with two Blue wires? located close to the Water Temp thermostat?if so the answer is yes,it is connected.
2 and a half ltrs in the actual rad,just over 4ltrs in the auxiliary tank(6 and a half in total)
The pump is located level with the bottom hose on the rad,and then a hose goes from the pump to the top of the aux:tank (located under the engine)then a hose from the rear of the aux tank to the inlet for the engine cooling jacket,round the engine and out (where the thurmostat is usualy located)back into the Rad.
I doubt if I have an air lock 'cos with the rad cap off Ican see the water whizzing round nicely (and with an air lock I doubt I would be able to get 6and a half ltrs into the system)
I am at present using the original rad fan which is way too fat and preventing me from getting enough room twix rad and mudguard without fan fouling the spark plugs,and the M/guard fouling the rad when braking(How did you overcome this?)
I hav'nt a W/Shop manual for the Commander so I used the carb settings for the Classic,I have more or less got them sorted(with some tips from Paul)
untill I have the overheating sorted so's I can give the bike a long motorway blast to fine tune them using the exhaust colour as a guide.
I am thinking of fitting two smaller low profile fans."A"to assist with the cooling and "B"more room twix rad and mudguard.
Any tips/advice will be most welcome. and photo's will have to come via a friend if I can find one willing enough.J.B.

[johnbirchjar]

As an afterthought,would NOT having antifreeze in the system make any differance to the cooling?and has anybody tried this new "Liquidless" cooling agent?I think Joe was toying with the idea of giving it a go.rgds,J.B.

[Richard Negus]

Hi John,
The first thing is that with a delivery of 4.5 litres/min your pump is too small.
I think when developing the F1, we measured the pump delivery at 3,000 rpm and got something like 16 - 18 l/min. The Commander uses the same basic impeller as the F1 so should have about the same flow rate.
Davies Craig make larger versions of the EPB with deliveries of 23 and 25 l/min; the EPB25 has 19mm spouts. All in the range are intended as boost pumps for auxiliary cooling of turbochargers etc.
My Commander, and that of Kev Traynor, uses an EWP80 which is an engine coolant pump delivering a maximum of 80 l/min, controlled by their own microprocessor which varies the pump speed according to the engine temperature. With that processor, you can set the engine temperature to whatever you like.

Leccy pump.JPG

What's the purpose of the auxiliary tank?

To get best cooling, the bypass passage should be blocked otherwise water can circulate around the engine without passing thro' the radiator.

I've found that no matter what the conditions are, factory standard carb settings work best. SAE40 oil in the dashpots and jet heights set to 0.128".
No need for fine tuning - if the engine's running badly with those settings, then something else is wrong.
Did you replace the O-rings in the choke mechanisms when you overhauled the carbs?
Idle air screws don't have needle ends so 'turns out' is irrelevant. Start with the screw heads level with the outside of the casting and then, when the engine is hot, screw them in until you have a smooth idle. If the engine doesn't respond to the idle screws, then that is possibly the cause of your problems.
I'm surprised you think an engine at 106,000 miles can be in good condition, unless of course it's been recently overhauled. I've just stripped a Commander engine at 114,000 to find the apex seals are worn to 50% of their original height, ten pin seal springs were broken, two were missing altogether, and the engine plates scored but salvageable.
R.

[johnbirchjar]

Hi Richard,Thanks for the info:
Seems like I need more powerful pump.
The reason for the auxiliary tank was that I had been informed that the capacity of the Commander cooling system is 5ltrs.my rad is 2and a half,so I thought(wrongly it seems) the overheating was down to lack of coolant,there is no room in the Triumph Fairing for a Header Tank,hence the Auxiliary Tank.Do you think with a much more powerful pump I may not need the Auxiliary Tank?(I expect I will leave it on anyway 'cos it's not in the way of anything)
Yep,EVERY "O" ring has been replaced.
If you used the Commander Rad & Fan did you also find it a bit tight for room twix Fan and Spark Plugs?
I have sent the VCR off to Eletrex World for their Tech: guys to run some tests to try and discover why it only passes on 13v to the Battery(should be 14.5)
My thinking on a 109,000mile engine is that it would be good for about another 40,000miles?(5/6 years riding?)and with me fast approaching my 78th birthday it would suffice ,and if it doesn't? I will just put the Classic engine back in the bike . I will keep the Forum advised,ride safe,J.B.

[Richard Negus]

John,
The coolant capacity of the Commander complete system is about 5 litres - that's all the water that goes into a dry system to fill engine, pump, hoses, radiator and header tank. The tank is only there to allow for expansion as the system warms up and a place for trapped air to collect. It doesn't perform any function in cooling the engine.
Spark plug access on a standard Commander is tight, to say the least! With the Chinese fan, I had to cut away some of the plastic shroud to clear the plug caps. Changing plugs with original or modified system is best done when the engine is cold.
R.

[Campbell]

.Are the rubber seals in the choke mecchcanism ok ? if not petrol will enter the carb. and flood it resulting in rough running and mission impossible when trying to get an even tick over I had this problem and when I renewed the seals all ok. All the best Campbell

[Richard Negus]

For those not familiar with the problem, this is the O-ring that causes the problem.

4280-25.jpg

On this bike, the O-rings were rock-hard, perhaps due to age or engine temperature and possibly hadn't been replaced in the bike's life.
When the carbs are assembled, you can't see them and I don't believe it's mentioned in the handbooks or workshop manuals.
This £1.50 O-ring can have a disproportionate effect on engine performance and fuel economy.
R.

[johnbirchjar]

Hi Richard,Was the Chinese fan any slimmer than the standard Commander one?'.cos like you say"It's a bit tight in there"and even a measly 10mm would make all the difference ,and if so where did you purchase it from?
I have managed to wangle enough room to get the plug caps off but no way is there enough room to get a plug out without undoing the Rad: bottom retaining bolts,fortunatly,(with an electric pump,) the rad is not directly connected to the bike's water Jacket so draining the system is not necessary ,but like you say,"Best done with a cold engine" .
I will order a more powerful pump tomorrow and report anon,and thanks guys for offering tips,ride safe,J.B.

[Richard Negus]

John,
I got it off Ebay, about £20 5 - 6 years ago. Not sure whether it was 8" or 9" fan with a moulded plastic mount. I didn't take a photo of it, but had to cut some of the plastic guard away. It just fitted between the top and bottom plates of the rad.
Much quieter than the standard fan and shifted a lot more air.
R.

[johnbirchjar]

Hi Richard,Thanks for the info.
I have "Modified" the fan mounting on Commander set up and gained a bit more room(eg,it sits higher up the rad,giving easier access to the plug caps,still doubtful if I can get a plug out though)
Am I right in thinking that if the whole of the back of the rad is encased,the fan will act like a Vacume Cleaner and drag air through the top AND bottom?
Have ordered the new Pump,should be here tomorrow.
Good news re: the VCR.Electrex World have tested it,found it faulty and are supplying me with a replacment ,unfortunately they are out of stock of that particular model untill the end of next week ,but hey,its for free so I don't mind waiting .I will report on progress,ride safe,J.B.

[johnbirchjar]

Hi Richard,Sorry to keep pestering you,red face.
Looking at the spec: & dimensions of that EWP80 you fitted,are the in and out pipes realy that big? ,45mm is a seriously big pipe ,or is it a printing error? (they don't look that sort of size in the advert pic's.)
Looking at the lack of room,perhaps a better option may be the EBP25,(25ltrs a min:minimum)do you think that will that be enough?(bearing in mind the extra coolant I have with the auxiliary tank)I realise the EWP80 would be a better option,but I am concerned about those pipe sizes (and the actual size of the pump)The EBP25 is a lot slimmer and the pipe sizes are only 18mm.rgds,J.B.

[johnbirchjar]

Further to my previous post,I have been in the garage and had a bit of a measure up and there is no way that the EWP80 will fit twix Rad and the Water Jacket ,so it looks like the EBP25 will have to be the choice.I suppose I could fit the '80 where Richard did,but it would look a tad unsightly,but, what the hell,at least I would know that I wouldn't have an overheating problem .(and the Auxiliary Water Tank hanging under the engine is not exactly a thing of beauty ,) I will ponder at length.ride safe,J.B.

[Richard Negus]

It's the flanges of the pump that are 58 mm! It comes with separate flanged stubs; you can see on my photo that 28mm bore hose can be fitted onto them.
Agreed it would look a mess without the Commander bodywork to hide it .
EBP25 should do the job but try to keep the hoses diameters as big as possible.
R.

[johnbirchjar]

Thanks for that Richard.
The next post on this subject from me will probably be after I have received and fitted the new Pump & VCR,hopefully the report will be full of good cheer ,ride safe,J.B.