ok new problem :(

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spike4073
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ok new problem :(

Post by spike4073 » 04 Mar 2010 09:21 pm

finaly got my 340 dl (cvt) running ok...ish however after 10 min or so of running it begins to run poorly and even cuts out

when checking all the usual things i find that the spark plugs are soaked in fuel.. so i clean them up and it runs ok again for 10 min or so then same problem, thought it may be running to rich at the mix but if i make the mix any more lean it wont idle without foot on gas.... any thoughts anybody?

monka
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Re: ok new problem :(

Post by monka » 04 Mar 2010 09:41 pm

can you not lean it out, but increase the idle speed?
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spike4073
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Re: ok new problem :(

Post by spike4073 » 05 Mar 2010 09:29 am

no.. if i increse the idle speed any more the transmission crunches when i change between n and drive and also if i increase it any more it tries to move when in drive and no gas applied wich a cvt should not do :S

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volvodspec
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Re: ok new problem :(

Post by volvodspec » 05 Mar 2010 01:10 pm

have you setup the carb with a warmed up engine or cold?

when it was setup on a warm engine it sounds like you've just covered up a sympton by adjusting it;

what condition is:
- oil + filter
- valve clearence
- ignition parts (dizzy, rotorarm, leads, plugs)
and have you checked the carb for faulty gaskets; arleaks; poreus membrames, blocked jets, worn o-rings, loose copper rings, leaking floaterneedle, floaterheigt etc?

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spike4073
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Re: ok new problem :(

Post by spike4073 » 05 Mar 2010 08:26 pm

carb is good as it was recently re-built , oil, filter, plugs and leads are new....dizzy cap and rotor arm are in good condition.

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spike4073
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Re: ok new problem :(

Post by spike4073 » 06 Mar 2010 05:07 pm

ok... have just descovered that its only firing on 2 cylinders checking seems to show spark at each plug....any ideas what the cause could be?..... was thinking possible loss of compression due to failed head gasket as the 2 that arent firing are next to each other

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Speedy88
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Re: ok new problem :(

Post by Speedy88 » 06 Mar 2010 06:11 pm

Get a compression tester, they're not that much money. A good engine will give immediate good compression readings.
'88 340 Williams (Sold)
'85 360 GLS - Drift project (Sold)
'77 Colt Sigma
'96 940 Drift project

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spike4073
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Re: ok new problem :(

Post by spike4073 » 06 Mar 2010 09:17 pm

ok will do that...

if it is lack of compression in the 2 cylinders should i be looking at changing the head gasket you think?

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volvodspec
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Re: ok new problem :(

Post by volvodspec » 06 Mar 2010 11:37 pm

if there is a really low compression on those cylinders than yes it's time to pop the head and inspect it

which cyl aren't firing? try cleaning the TDC sensor first or replace it with one you know is definatly ok

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spike4073
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Re: ok new problem :(

Post by spike4073 » 07 Mar 2010 12:06 pm

counting from the end nearest the dash.... its 1&2 that arent firing...... have checked and all plugs are firing.....so figure it must be a compression issue??

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volvodspec
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Re: ok new problem :(

Post by volvodspec » 07 Mar 2010 09:38 pm

yeah possibly but i'm stunned; i have never heard of this before on the 1.4 and i know these engines from 76 till 92 and from running great till reving into destruction...

the 1.4 headgasket is very rare to fail compression wise; it could also be 2 broken liners but 2 at a time on a bone stock engine is just as rare.... in the "out of the box" thinking style; the camshaft has a weak point right after the distributor link, the cam could have broken just behind that due to non properly lubricated cam bearings on the first 2 cylinders...

that probably means engine=exit; but you can check this to be sure by removing the valve cover and rotating the crank a few times; if the valves on those cylinders aren't working you know enough

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volvodspec
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Re: ok new problem :(

Post by volvodspec » 07 Mar 2010 09:41 pm

you do get fuel into those cylinders?

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spike4073
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Re: ok new problem :(

Post by spike4073 » 09 Mar 2010 09:30 am

yes i get fuel to them..

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spike4073
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Re: ok new problem :(

Post by spike4073 » 09 Mar 2010 12:33 pm

ok. ive had the head off and descovered that one of the valves is stuck in the open position....woud this cause the poor running and anyone know how to fix this??

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Speedy88
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Re: ok new problem :(

Post by Speedy88 » 09 Mar 2010 12:48 pm

Is the valve seized? Is it attached at the top?
'88 340 Williams (Sold)
'85 360 GLS - Drift project (Sold)
'77 Colt Sigma
'96 940 Drift project

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