Down on power.

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Henry
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Down on power.

Post by Henry » Sat Oct 03, 2009 9:13 pm

Hi all.

I have a problem, and i carnt for the life of me figure out what is causing it. If i start up the sj, it will rev fine up and down the range while out of gear. When it ticks over, it sits at 700 rpm and its spot on, smooth as anything.

However if i drive it, and give it the beans it really seems to be holding back. Sometimes it pops from the air filter and really seems to be lacking something :?

It has new plugs and leads, and the cap and arm where new only 6 months ago. The reason i say this is because the old engine would rev fine and have loads of "punt", but this one dosent.

Now the only thing that springs to mind is that i changed the oil in the SU and it was just straight 15/30 oil. The garage said it would be fine but i remeber Nigel Head saying somewhere it should be some special kind of oil. Would this cause the problem?

Henry

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Re: Down on power.

Post by bourneyo » Sun Oct 04, 2009 12:30 am

I had a similar problem, my jets were blocked no my nikki, took it to a carb specialist who blasted it out with a high pressure air line, set it all up again and she ran sweet as a nut!

dan 8-)
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Re: Down on power.

Post by Henry » Sun Oct 04, 2009 9:33 am

Ive been led to belive that it is a timing issue.

Something to do with the advance/retard mec? :|

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Re: Down on power.

Post by Angie » Sun Oct 04, 2009 2:24 pm

Sounds simular prob i'm having with my sj at the mo, hates hill starts and if i stick toe down quick, i was thinking maybe the big wheels are to big and the little engine is struggling, It seems fine reversing up a hill tho!!!! maybe i should just drive round in reverse lol

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Re: Down on power.

Post by Henry » Sun Oct 04, 2009 6:16 pm

I shouldnt have any power issues running a rocklobster and 1600.

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Re: Down on power.

Post by ROBBIE » Sun Oct 04, 2009 10:12 pm

henry-the-hoover wrote:Ive been led to belive that it is a timing issue.

Something to do with the advance/retard mec? :|
could be are the pipes ok not blocked or dameged?
Sid James gone but never forgotten
Jimny 1.6 not as good as an SJ but still good

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Re: Down on power.

Post by Henry » Sun Oct 04, 2009 10:24 pm

ROBBIE wrote:
henry-the-hoover wrote:Ive been led to belive that it is a timing issue.

Something to do with the advance/retard mec? :|
could be are the pipes ok not blocked or dameged?

The vac pipes?

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Re: Down on power.

Post by TAZ » Sun Oct 04, 2009 11:40 pm

I had the same problem, not on a suzuki but on a reliant, it starts and ran well, but didnt have any power, it couldnt pull us up the smallest of hills in 2nd and only got to around 50mph and it was screamming its nuts off, might be worth looking at the temp guage aswell

The problem was the timing, once i re timed it and slightly modded the curve it transformed it, cured the running hot and gave it lots of power

As for the dash pot, i use 3 in 1 oil and top it up after so many miles, its taken me all round the isle of man, from london to liverpool over 5000 miles with me only needing to top it up once. You will feel the problem when it needs topping up , you put your foot on the throttle and it doesnt rev and runs like its missfiring

Might be worth checking the plugs, if oiled up or black then it could be running rich and would make it lumpy. The plugs should be clean and grey ish, also check the exhaust, if its black sooty or spitting out black gunk it could be overfuelling

Hope this helps :mrgreen:

Luke

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Re: Down on power.

Post by ROBBIE » Mon Oct 05, 2009 10:40 am

henry-the-hoover wrote:
ROBBIE wrote:
henry-the-hoover wrote:Ive been led to belive that it is a timing issue.

Something to do with the advance/retard mec? :|
could be are the pipes ok not blocked or dameged?

The vac pipes?
Yep
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Jimny 1.6 not as good as an SJ but still good

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Re: Down on power.

Post by Tramp » Mon Oct 05, 2009 7:28 pm

to test the advance mechanism, take the vac pipe off on the carb and as it sits on tickover 'suck' the pipe, the revs should pick up while you are sucking, and then drop off when you stop, that way you know if the mechanism is seized or the lines are blocked,

to me it doesn't sound like the advance as some people run with out the mechanism and they still have enough power, it sounds like your timing needs setting,

Luke

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