misfire above 2500revs

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drummer

misfire above 2500revs

Post by drummer » Thu Jul 03, 2008 10:00 am

hi this is my first visit to this forum.im onto my second bongo but the first ever problem.it all started at easter,first my top hose burst causing my head to cook,i got a head from ebay and had it skimmed and pressure tested,while fitting it i found the water pump was worn so i replaced that as well,when finished i started the motor only to find that it misfires and smokes badly over 2500 revs but runs perfectly below 2500,it will run for an hour no problem,water does not is not pressurising and not overheating ive also had the turbo off and that is ok,any suggestions are welcome,cheers.
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Re: misfire above 2500revs

Post by scanner » Thu Jul 03, 2008 10:25 am

That sounds like an injector or injector pump problem.
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Re: misfire above 2500revs

Post by francophile1947 » Thu Jul 03, 2008 11:52 am

Could it be fuel starvation? Have you checked your fuel filter and the little banjo filter on the fuel pump?
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Re: misfire above 2500revs

Post by scanner » Thu Jul 03, 2008 11:55 am

francophile1947 wrote:Could it be fuel starvation? Have you checked your fuel filter and the little banjo filter on the fuel pump?
Why would starvation cause smoke? That is usually too much fuel, not too little.

More likely to be a blocked air filter - have you checked that?
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Re: misfire above 2500revs

Post by francophile1947 » Thu Jul 03, 2008 12:08 pm

scanner wrote:
francophile1947 wrote:Could it be fuel starvation? Have you checked your fuel filter and the little banjo filter on the fuel pump?
Why would starvation cause smoke? That is usually too much fuel, not too little.

More likely to be a blocked air filter - have you checked that?
I don't know, that's why it was a question - just seem to remember a similar post in the past :?
John
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drummer

Re: misfire above 2500revs

Post by drummer » Thu Jul 03, 2008 7:31 pm

i forgot to say,new oil filter,fuel filter and air filter,where is banjo filter?,cheers.
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missfixit70
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Re: misfire above 2500revs

Post by missfixit70 » Thu Jul 03, 2008 7:35 pm

On top of the fuel pump, you'll have to firkle it out with a cotton bud or magnetic screwdriver tip thing, it's only just bigger than the cotton bud head, be very careful with it.
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Re: misfire above 2500revs

Post by daveblueozzie » Thu Jul 03, 2008 8:03 pm

FIRKLE :shock: is that a technical term :lol:
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Re: misfire above 2500revs

Post by scanner » Thu Jul 03, 2008 8:04 pm

You'll know that if Kirsty ever Firkles you with a cotton bud.
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Re: misfire above 2500revs

Post by missfixit70 » Thu Jul 03, 2008 8:05 pm

Yep, as is FUBAR & NFG :wink:

Scanner :shock: [-X :lol:
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Re: misfire above 2500revs

Post by mikeonb4c » Thu Jul 03, 2008 11:01 pm

If I'm not fettling, I'm forever firkling or fiddling or faffing or sometimes just effing about
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Re: misfire above 2500revs

Post by bigdaddycain » Fri Jul 04, 2008 3:53 am

Hi Drummer, when you say "misfires above 2500rpm",could that also be construed as a reluctance to rev beyond 2500rpm, accompanied by coughing and spluttering?

I'm thinking that your fuel pump could be leaking, and taking in air,and not suppliying sufficient amounts of fuel when the demand arises? Or perhaps one of the pipes to the fuel pump has sprung a leak?
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drummer

Re: misfire above 2500revs

Post by drummer » Fri Jul 04, 2008 1:48 pm

thanks to all for your suggestions,theres plenty of fuel at the injectors cos i checked that there was a flow at the return pipe when revving hard so i think starvation is out of the question,but how can i check the injectors?,can they be cleaned,.ive put a full can of injector cleaner through it?.cheers
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