Well went to Oulton Today for first one of the year and although I still had a great day (and met a couple of faces from here ) the car did develop
a quite serious misfire by the end of the day.
In the morning it was present but by the afternoon it was so bad I didn't dare drive it any more
What should I look at?
Car is 893 Blade and has been stood for maybe a couple of months. Plugs and leads in good condition any ideas would be welcome because I had this
before back in August and replaced my carbs which had cured it up till now so maybe it didn't cure just hid?
As always any help is much appreciated
Cheers
Eddie
I'd start by taking the carbs. off and cleaning them out, bike carbs always seem susceptible to being left with fuel still in them.
try running some petrol injector cleaner through the carbs first b4 taking them off i never had a problem with my megablade doing this .check and clean earths .take off plug caps and spray with wd incase theres any damp same with all leads .also check battery level this did happen to me once .any more info pm me on wscc
Try the fuel pump. Blade fuel pumps can be very temperamental.
Phil
Cheers guys,
I would love it to be something easy because I spent ages cleaning the last set of carbs before finally replacing them. Only for it to be doing it
again
Fuel pump is interesting because I have just had that same conversation with Chris over at the BEC center and he has a couple lying around so
hopefully can try it and see. Fingures crossed!
Ive had a couple of Blade pumps that stop and start on me for no apparent reason.
I would also try some new good quality plugs. I bought some from a bike shop I think they were NGK but never ran as well as the set from Honda. It
developed a serious misfire then cylinder 3 just stopped altogether.
New set of plugs from Honda and never had another problem.
Steve
quote:
Originally posted by Howlor
I would also try some new good quality plugs. I bought some from a bike shop I think they were NGK but never ran as well as the set from Honda. It developed a serious misfire then cylinder 3 just stopped altogether.
New set of plugs from Honda and never had another problem.
Steve
Nice to meet you today Eddie. Shame I am probably LB's least technical member but I hope you get it sorted. At least my theory of the fuel pump
is one shared by others!
I see you're at Oulton next month too, I'll hopefully see you there
had the same problem at oulton park in my old blade car and that was a fuel pressure fault making it run lean under load
Rich
Here is pic of where regulator is (top left of pic) I had one blow when I first started driving the car and so fitted a finned one and the PC fan you
see above it which keeps the temps right down:
Hi Jubal yeah good to put a face to the name. I will be there next month so just need to sort this little niggle out because otherwise the car is
going great
Cheers
Eddie
quote:
Originally posted by ChrisGamlin
Have your carbs been rejetted Eddie?
Ok (this will show my lack of knowledge )
Right bought some new plugs and was about to fit them so started removing the old (well not that old) ones and noticed that all were fine except
cylinder 3 which was dark.
This is the embarassing bit:
I think this means that it is a bit rich on cylinder 3?
Also if that is correct then can you change the A/F mixture just on 3 ie through carbs and so is this not a feul pump issue?
Thanks
Eddie
Hi, Eddie
It is worth checking that the vacum take off points on the inlet ports are blanked off correctly. Carb Blade engines have always had a problem with
No:3 cylinder fouling plugs.
The little rubber blanking plugs, removed when balancing the carbs, become loose fitting over time. It is always number 3 that falls off, leading to
the problem you describe.
Hope this helps
Tim
Cheers for thought Tim.
Unless I'm looking at the wrong bit (possibly ) my vacuum take off points are srews and not caps so I have checked and they are all tight.
One bit of information that has come to light is that when I pulled into the pits once the missfire was getting worse, I remember a freind of mine
(also there in an RX-7) mentioned that the HT lead going into the coil seamed loose and pushed it into place. From memory and after looking at the
plugs today I believe it was the No 3 take off from the coil.
With this new info to light would it be fair to think that somehow the HT lead had worked loose (maybe after taking the bonnet off to show Jurbal -
your fault mate ) and therefor produced a weak spark causing missfire and plug to foul up?
If that did happen then even though we found the lead was loose by this time the plug would already be fouled and so the missfire would still
occur?
Is my little theory plauseable or is this wishful thinking?
Cheers
Eddie
If I remember correctly, on the underside of inlet port of No3 there's a small vacuum take-off pipe which is used to shut the fuel off when the
engine is stopped. Usually in a car install you're not using this fuel shut-off valve so if this hole isn't blocked off it will allow air to
bypass the carb and muck up the fuelling on that cylinder, which will cause running problems.
Chris
A loose plug lead could cause issues as well yes. It might run OK when stationary blipping it in the pits etc but could start breaking down when the engine is under load.
quote:
Originally posted by ChrisGamlin
A loose plug lead could cause issues as well yes. It might run OK when stationary blipping it in the pits etc but could start breaking down when the engine is under load.
Ok new plugs in all leads checked and it still misses at high reves even from reasonably cold (I always let temp get up before going over
8000rpm) so does this imply fueling?
Cheers
Eddie
Hi Eddie
A duff lead could cause the blackened plug because there would be fuel going in that wouldnt be burning every cycle, so when it did ignite it would be
a rich mixture.
You could try temporarily swapping the coilpacks around and see if the problem followed.
quote:
Originally posted by ChrisGamlin
Hi Eddie
A duff lead could cause the blackened plug because there would be fuel going in that wouldnt be burning every cycle, so when it did ignite it would be a rich mixture.
You could try temporarily swapping the coilpacks around and see if the problem followed.
Have you checked for that air bleed under the carbs that I mentioned above?
Looked for it but couldn't find anything that looked like you mentioned
I'm thinking that I possible had 2 issues at once which made the missfire worse.
Fuel pump and knocking the HT lead out of the coil.
I figure if I change one thing at a time then all will become clear
Ok for anyone that comes accross this problem with their car it turned out it was the fuel pump
Flow rate seemed fine at power on but I guess that would explain why the car ran ok at lower revs. Then I guess it couldn't keep up at the higher
revs.
Replaced with Fireblade pump and all sorted. Rev bashing Blade back again!
Glad you got it sorted
Pleased you got the problem sorted Eddie.I was at Oulton Park that day (spectating) didn't get there until dinner time though. Shame I didn't get chance to meet you. It looked very wet out there!
Nice one Eddie. See you next month.