Briggs & Stratton powered Falco

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Aladinsaneuk · #16 Post by **Aladinsaneuk** » Mon Jun 09, 2014 5:23 pm

Coils......

KitchenSync · #17 Post by **KitchenSync** » Mon Jun 09, 2014 6:24 pm

I just stuffed an old plug in and there's a spark in both leads.

Now working out how to tell if the injector circuit is doing it's thing.

KitchenSync · #18 Post by **KitchenSync** » Mon Jun 09, 2014 7:53 pm

The mystery deepens...

Getting both sparks ok and both plugs are pretty much brand new.

I plugged the rear cylinder injector lead into spare throttle body and there's definitely some squirty relay action going on - I could see petrol jumping around the injector nozzle.

This engine was running prior to removal and shipping - so there's definitely a piston in there.

I thought I'd nailed in this morning but no... and I'm at a loss as to what it might be.

cmdrew · #19 Post by **cmdrew** » Tue Jun 10, 2014 10:53 am

On mine from memory there was a bunch with 3 wires together and then 2 other single ground wires. Check all ground wires are connected. Also check that the cam sensor for the front cylinder is plugged in as that is how the engine determines which cylinder is at TDC apparently.

If both plugs are sparking and you are getting fuel injected on both then I doubt that is the problem. You could try just pouring a little petrol into the throttle body for the rear cylinder and see if it starts on both just to confirm if it is a fuel or ignition related issue. Watch out for it firing back through the throttle body though - keep the tank up and do not lean over the throttle body while doing this!

KitchenSync · #20 Post by **KitchenSync** » Wed Jun 11, 2014 7:56 pm

All the earths are earthed. Squirted some juice down the throttle body while it was chugging away on the front cylinder but it made no difference.

I've yet to transpose the coils - but I'm not sure how they could both fail at the rear... and there IS a spark from both leads. But in the great process of eliminating everything I'm one step off smelting the bike down to its constituent elements and making a new one from scratch.

spiderwheels · #21 Post by **spiderwheels** » Wed Jun 11, 2014 8:04 pm

KitchenSync wrote:All the earths are earthed. Squirted some juice down the throttle body while it was chugging away on the front cylinder but it made no difference.

I've yet to transpose the coils - but I'm not sure how they could both fail at the rear... and there IS a spark from both leads. But in the great process of eliminating everything I'm one step off smelting the bike down to its constituent elements and making a new one from scratch.

Sounds like an interesting project. Make sure to share the pictures :)

Falcopops · #22 Post by **Falcopops** » Thu Jun 12, 2014 6:10 am

KitchenSync wrote:All the earths are earthed. Squirted some juice down the throttle body while it was chugging away on the front cylinder but it made no difference.

Have you established that there is a spark in the back pot?

I only ask as I've tested the leads with a spare plug, but what was actually happening in the cylinder was the plugs were so badly fouled that they were shorting to earth instead of sparking. just my 2p worth.

Given that you only need fuel and fire make a bang, seems like the spark is absent or mistimed. Unless the cams are half a turn off.

KitchenSync · #23 Post by **KitchenSync** » Thu Jun 12, 2014 12:37 pm

I'll try switching the plugs for old ones. When I pulled them out they seemed almost brand new - the RSV had just been serviced and was laid up in a dealer bankruptcy sale before the engine was pulled, still had an MOT, no question about it running beforehand.

But having said that... while the front is firing, how well is is firing?

Anyone out there prepared to pull their rear plug leads and tell me if their version of a 495cc compressor sounds the same as mine? It might indicate there's some overarching problem affecting both and I'm just lucky it's running on one cylinder.

D-Rider · #24 Post by **D-Rider** » Thu Jun 12, 2014 12:48 pm

In the past, mine has run as a single on several occasions. Tends to happen when it floods on one cylinder and is often quite difficult to clear.
Brown-trouser moments a-plenty when the second cylinder cuts in - transforming from compressor to meaty power source. A bit too entertaining on damp roads.

The sound yours is making is fairly consistent with what I remember.

fatboy · #25 Post by **fatboy** » Thu Jun 12, 2014 8:19 pm

Falcopops raises a valid point, fouled plugs DO give a mis- directed spark.
A slave plug may spark ok but that does not tell you if your dirty fitted plug is working under load.
Try at least 2 new plugs and see what happens

gramey · #26 Post by **gramey** » Thu Jun 12, 2014 10:07 pm

Random thought for the day , have you checked your plug caps, when I bought mine it was running slightly rough, not on one cylinder but not right, and one of the plug caps was broken inside. :)

KitchenSync · #27 Post by **KitchenSync** » Sat Jun 14, 2014 1:33 pm

So... just switched out the rear plugs for a couple of spares - no difference.

Switched easiest to get to coils front to back - no difference

Without rear plugs there's was a healthy petrol 'vape' squirting in my face.

No diagnostic errors. Battery now dead so playtime's over but I think I'll jump on the bus and go buy a new one.

I'm now looking at the ECU and thinking is it cooked?

spiderwheels · #28 Post by **spiderwheels** » Sat Jun 14, 2014 1:54 pm

Does the rear cylinder does have compression?

KitchenSync · #29 Post by **KitchenSync** » Sat Jun 14, 2014 2:19 pm

I've not got my compression tester here in Nottingham. The batteries fooked now anyway so I can't do any more today.

Could this be a stuck valve? The engine was standing for six months... it seems highly unlikely but as Sherlock said '...when you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth.'

I've just admitted defeat and have a mobile guy turning up in the morning. It's not fun any more and I need more eyes on this to see what I'm missing.

zoidberg · #30 Post by **zoidberg** » Sat Jun 14, 2014 4:01 pm

gramey wrote:Random thought for the day , have you checked your plug caps, when I bought mine it was running slightly rough, not on one cylinder but not right, and one of the plug caps was broken inside. :)

i had this too, a huge improvement was had when i replaced the leads