SR3 fuel filter

Author
Discussion

silverthorn2151

Original Poster:

6,307 posts

185 months

Saturday 27th March 2010
quotequote all
We had the Radical on the lift yesterday to do a days fiddling ahead of the seasons trackdays. Did all those bits that you normally do and added some things. We got a fuel filter from Radical. Time ran out on us, as it normally does, but have to confess that we simply couldn't find the filter!

Any ideas where we should have looked?

splitpin

2,740 posts

204 months

Saturday 27th March 2010
quotequote all
Not sure whether it's in the same place on the older cars, but it may help to have a look on Page 11 of the new SR3 RS Owners Manual? >

http://redirectingat.com/?id=1044X509854&url=h...

Marshy98

169 posts

224 months

Saturday 27th March 2010
quotequote all
Hi

The fuel filter is under the passenger side pod.

Regards

Marshy

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
We didn't get around to changing the filter yet, partly as we haven't worked out how to get the side pod off.

However!

Now I'm wondering if the filter is at the root of a problem we are having. We run an more or less standard Hyabusa 1300 (originally it had a 1100 Kawasaki unit). It's been running brilliantly, but we are plagued by a bad misfire that we just can't trace.

We ran it at Snetterton a couple of weeks ago, and it ran pretty well fine all day.

Took it to Bedford on Monday and it was getting worse as the day went on. So bad in fact that we were concerned about the drivetrain loading and unloading so violently that we didn't want to break anything. The symptoms are that when accelerating hard it seems like there is a momentary loss of power completley, rather than just one pot missing. It can jump like that a few times and then carry on. Seems to have no consistency in terms of rev range. I tried short shifting for a couple of laps, but it still did it.

It seems worse as they day goes on. We've checked all connections, changed plugs and all the usual things you might expect. We did think the fuel pump might be giving up but it seems to have the correct pressure on the guage according to Dereck at Radical....who I have to say was REALLY helpful on the phone.

I've been doing some web research and people do complain of misfires on Hyabusas and the fuel filter seems to be mentioned a lot. To be fair, they also mention running fuel with a high rating and exhaust leaks.

Any ideas chaps?

dsl2

1,475 posts

207 months

Wednesday 28th April 2010
quotequote all
Mmmm, does your installation run a separate coil pack ala Powertec or the original busa caps that generate the sparks?

My PR6 did something similar to yours & it turned out to be the coil pack failing..........

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
The original caps. I believe these incorporate the coils.

Been doing a bit more research and Busa owners report similar problems if the exhaust is leaking ot the manifold isn't tight. We haven't checked that to be fair and it does seem worse when it's hot.

splitpin

2,740 posts

204 months

Wednesday 28th April 2010
quotequote all
If you've got the original 'pontefract cake' wobbly spark plug caps, it could easily be those; dump them and fit a set of proper 'sit-in' Magnecors.

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
We did decide to change caps and leads. Can you point us towards a supplier for those?

Marshy98

169 posts

224 months

Wednesday 28th April 2010
quotequote all
Hi

The side pod removal is a 5 min job for 2 people ideally, disconnect the aux battery supply and wheels and it slips off, i change my fuel filter and then found the fuel pumps were getting a bit tired, there a 2 fuel pumps, 1 to pump fuel into the anti surge tank incorperated it the main tank and 1 to pump to the carbs via the fuel filter, if the first pump does keep up with the demand of the second then you will get fuel starvation, i replaced both pumps, about £40 each from fuelpumpsonline.

Hope this helps.

Marshy

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
Oh, this is excellent chaps, and is making me/us feel like chumps. Hadn't picked up about the second pump. We talked about the swirl pot being starved as the misfire feels like a fuel issue rather than spark.


splitpin

2,740 posts

204 months

Wednesday 28th April 2010
quotequote all
silverthorn2151 said:
We did decide to change caps and leads. Can you point us towards a supplier for those?
Ironically, this shows the ones you probably have (?) and definitely need to get shot of >

http://secure2.cyberware.co.uk/~rad-shop/acatalog/...

That said, I think the photo is simply well past it's sell-by date i.e. order this part number and you'll actually get proper sit-in Magnecors from the Big R.

Obviously, best speak to Ben in parts to clarify.

If you scratch around on the web with the usual suspects you'll doubtless get them cheaper, say 25%? But personally, I'd like to be sure that I have someone to point the digit at if the wrong ones got supplied. IMHO, that's worth a bit extra folding.

Good chance of this sorting it out; been there, done that, one minute it's misfiring, then it's gone for a while, then it's back again, sounds just like the pontefracts playing up; don't waste time trying to salvage them; replace and put them in that big really rainy day spares box.

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
Thanks again.

I agree, rather know the bits are right than save a few quid.

We are going to:
1. Change the leads
2. Get the side pod off and change filter and pump
3. Check exhaust fixings
4. Polish it (can't hurt eh?)


Simon T

2,136 posts

279 months

Wednesday 28th April 2010
quotequote all
If it cuts as violently as you indicate this very unlikely to be fuel and much more likely a total ignition fault especially on a carb engined car as the fuel in the float chambers buffers any sudden but transient fuel flow interuption, intermittent fuel starvation has a much more 'gentle' effect
Worth checking the fuel filter anyway as on older cars the tank foam can start to break up and clog the filter. This can cause your engine to run too lean at high rpm/throttle openings - a great way to destroy an engine.

Another known problem that will cause these symptoms is the Master cut out switch, I have had one fail and heard of others. It's vibration related and intermittent, cuts the power for a split second, difficult to pinpoint but you should consider replacing it if you have a spare

Simon

Edited by Simon T on Wednesday 28th April 19:26

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
We have fuel injection rather than carbs but I do know what you mean about it logically being electrical, it just doesn't feel electrical.

It's going to be a case of working through components until it stops happening. One of the problems is testing the cures. Can't reproduce it in the garage or on the dyno, only on track.

The cost of changing components is insignificant compared to the cost of getting out on track so I think the switch is a good call.

Simon T

2,136 posts

279 months

Wednesday 28th April 2010
quotequote all
Even with FI I think it would be a failure of the FI electronics rather than the fuel delivery system. The symptoms you descirbe would have to be all injectors delivering no fuel at the same time rather than not enough fuel pressure or flow through injectors that were firing normally?

S

splitpin

2,740 posts

204 months

Wednesday 28th April 2010
quotequote all
100% with Simon on this; it's electrical.

Clean up / replace all the main/ignition related fuses.

Recheck all the connections including those to the secret pump.

Check wiring continuity, including mate shaking said wiring.

If you've got those wobblys replace them.*

Replace the master switch; it's cheap as chips in the overall scheme of things.

Go to track, cross fingers, touch wood and all being well, enjoy.


  • Even if not already, they will fail at some point and you'll start misfiring / going onto 3 (that does the engine no good at all) and if they start arcing (the leads themselves on those are as floppy as hell), that could knock out two which is as good as four gone AWOL on a 4 pot. Incidentally, when you fit the Magnecors (or any leads on any motor come to that) arrange them carefully and secure where appropriate so that no lead touches the other even when the motor is vibrating like a good 'un.

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 28th April 2010
quotequote all
Logically you're right it has to be electrical, or is at least more likely to be. We have had the problem for some while, but it seems to be getting worse. We have checked all connections we can see, had the systems checked (we have an ETB digi-dash wheel and datalogger) and all seemed ok on the electrical side. On the dyno recently they found a possible plug breadown, so changed them.

The frustration is that when it's not missing it's running like a train! It was frustrating on Monday at Bedford as it was very quick round there, and still was between misfires, but as I said before we felt it was risking damage to transmission and shafts as it was mostly under hard acceleration.

Chris

gaxor

331 posts

259 months

Wednesday 28th April 2010
quotequote all
Masterswitch is a good call,we had this happen on our original Clubsport. We now always carry a spare

Gary

silverthorn2151

Original Poster:

6,307 posts

185 months

Wednesday 9th June 2010
quotequote all
Our misfire saga is still ongoing.

We are now concentrating on it being a fuel related problem rather than electrical. Seems that we have the standard SR3 tank, but it's now about 6 or 7 years old. When the engine was swapped for the 1300 Hybusa the fuel system was played around with. We have no fuel filter it seems.

It's been suggested that the foam in the tank could be breaking down and obstructing the outlet in some way causing starvation which leads to us having an air pocket in the common rail. The misfire happens under hard acceleration out of left hand bend, and particularly after heavy braking.

We have the car in bits at the moment and will be playing and checking all day Friday. According to Radical they did have some misfire issues relating to problem tanks, paticularly when fuel got below 20 litres.

You guys have any views on the above as a scenario. We are starting to think we need to have a new fuel tank made (Radical want loadsa quids!). We need to include a filter in the line somewhere, need to change the pumps. will cleaning the injectors do, or should we replace?

Desperate to get it back on track as when it runs, it's fabulous!




splitpin

2,740 posts

204 months

Wednesday 9th June 2010
quotequote all
silverthorn2151 said:
The misfire happens under hard acceleration out of left hand bend, and particularly after heavy braking.

We have the car in bits at the moment and will be playing and checking all day Friday. According to Radical they did have some misfire issues relating to problem tanks, paticularly when fuel got below 20 litres.
Notwithstanding that you should definitely have a filter (it always surprises me how much contaminant there is in depot fresh petrol), that's a very/strangely specific problem, which suggests to me something related to something being amiss with the tank pump pick up. Does the problem still manifest itself when you run on a full tank?