lumpy/rough running

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jrt
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lumpy/rough running

Post by jrt »

Hello, van just started to run a bit rough today.
Was ok before, drove half an hour, stopped to fill up and then started to feel a bit under powered than usual on remaining journey. I have tested the resistance of the ht leads and the king lead with a multi meter, the king is 2000 ohm and the ht leads are 6190, 6190,6220 and 5780. From what i can gather the king lead is spot on but what about the ht leads, would them being just over 6000 ohms be a problem ?
Just been back out to the van and tested the out put of the coil( green)..the secondary reading is 2850 and the primary is zero...is this coil goosed then? Sorry for the questions , i'm out of my depth here!
Plugs/rotor arm/dizzy cap/ fuel filter all ok. wbx dg 1.9
Cheers David
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jrt
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Re: lumpy/rough running

Post by jrt »

After more checks this morning it looks like the vacuum advance unit.Is it a simple job to replace it?
David.
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lodgey62
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Re: lumpy/rough running

Post by lodgey62 »

Had a similar situation it was the ignition amplifier
1989 Autosleeper Trooper 1.9 petol
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jrt
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Re: lumpy/rough running

Post by jrt »

lodgey62 wrote:Had a similar situation it was the ignition amplifier
Yes i've been reading through a few posts on here today, i saw yours. I've not had any stalling/hard starting etc. Just had a nagging feeling the van wasn't running right yesterday, it wasn't really noticeable at first then the usual hills i flew up in 3rd i had to go up in 2nd so knew something was up. So i replaced plugs, inspected/tested leads,coil,dizzy, vacuum pipes and cleaned up all connections etc, that was when i found the vacuum advance unit was goosed. Got one ordered so will fit that this week and get my mate round with his timing gun and take it from there. I will bear it in mind tho'.
David.
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jrt
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Re: lumpy/rough running

Post by jrt »

...going to buy a better multi meter as well.
David
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lodgey62
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Re: lumpy/rough running

Post by lodgey62 »

Sounds like my method of cure,in the end it was a toss up between the distributor and the ignition amplifier,the amp was the cheeper and cured it,if you can get to Halifax your more than welcome to try mine. :ok
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jrt
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Re: lumpy/rough running

Post by jrt »

Afternoon all. Right still having a few issues with the running of the van.Can anyone advise where to check next.
Starts ok, idles ok, pulls off ok and goes through the gears but every now and then it feels "feathery" and under powered,seems worse when getting some speed up in 5th....doesn't like that
Checked the ht leads,dizzy...put a new arm on again just to be sure, coil ohms seem ok, new fuel filter, new plugs, checked manual fuel pump-the push rod measured 99mm in length..is this ok, checked all vacuum pipes and sprayed carb' cleaner around gaskets etc to check for leaks, new vacuum advance unit and timing sorted (idles better than ever now). 1.9 dg wbx '83.
Cheers David
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itchyfeet
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Re: lumpy/rough running

Post by itchyfeet »

check earths to head and under coil
also try running a fresh temporary 12V connection from stud in black box to coil
this will need a fuse , say 15A and need removing to switch engine off.
it rules out a bad ignition 12V, your coil takes more power when revs are high any any bad conection could limit spark at higher revs
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jrt
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Re: lumpy/rough running

Post by jrt »

thanks , will do.
David
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Re: lumpy/rough running

Post by jrt »

jrt wrote:thanks , will do.
David
hmm just been to have a look again, i'm afraid i don't have a clue what to check..sorry...never done any electrics :oops: when you say check earths do you mean the wires attached to the side of the engine bay under the coil? as for the black box i've no idea what to look for in there..what's the stud?
apologies David.
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itchyfeet
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Re: lumpy/rough running

Post by itchyfeet »

yes clean up.earths to.engine head by distributor, brown wires and under coil, brown wires
this means removing the bolt or nut and cleaning up.with wetand dry.or a wirebrush and replacing with vaseline or petroleum jelly
start there and we can move onto.the 12V
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jrt
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Re: lumpy/rough running

Post by jrt »

cheers, will have a go after work tomorrow. Would the slightly worn fuel push rod cause a problem when trying to floor it ..(98.5mm approx) ?
David.
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itchyfeet
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Re: lumpy/rough running

Post by itchyfeet »

jrt wrote:cheers, will have a go after work tomorrow. Would the slightly worn fuel push rod cause a problem when trying to floor it ..(98.5mm approx) ?
David.

I doubt it
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jrt
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Re: lumpy/rough running

Post by jrt »

Just got in. Cleaned up the earths, double checked the ht leads and petrol pump function. Took it for a short spin...goes through from 1-4 ok, little bit of "feathering" now and again, changing down 4 to 3 pulls great but 5th is like towing a parachute and i have to change into 4th.
David.
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itchyfeet
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Re: lumpy/rough running

Post by itchyfeet »

begning to sound like fuel not ignition, 2nd throttle not opening?
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