AAZ - Erratic Tick Over

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DokaDave
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AAZ - Erratic Tick Over

Post by DokaDave »

Hi All
I am having problem with the tick over with the AAZ and wondered if anyone had any ideas where to start????????
The engines starts first time every time, and when cool ticks over @ approx. 850RPM, when the engine then gets warmer the tick over RPM becomes erratic and can be anything between 1000RPM and 1300RPM at standstill.
I have also noticed that when the revs come off and drops it does not fall smoothly the rev falling rate slows around 1800 -2000RPM before falling to a high tick over.

I have lubbed and check the linkages all appear to be in order to my untrained eye!!

Any pointers would be greatly appreciated

Thanks

DD
1990 DoKa Syncro 1.9AAZ


Imagination is more important than knowledge.

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Oldiebut goodie
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Re: AAZ - Erratic Tick Over

Post by Oldiebut goodie »

Cold start advance needs backing off a little? Have you a manual advance on your pump? Mine needed adjustment after I increased the fuel on my 1Y pump.
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DokaDave
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Re: AAZ - Erratic Tick Over

Post by DokaDave »

Thanks for the tip, I have a manual and will take a look
DD
1990 DoKa Syncro 1.9AAZ


Imagination is more important than knowledge.

DokaDave
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Location: Doncaster

Re: AAZ - Erratic Tick Over

Post by DokaDave »

Checked out the problem some more today and it appears the cold start mechansim has not been fitted when the AAZ was fitted. The drop off is now smooth following some lubrication.

However. there still remains the problem when I start the motor it ticks over ok at 850RPM and then rises to 1400RPM when the engine is fully hot. When I stop the engine and then restart it following a short break it again starts off at 850RPM and then slowly rises to 1400RPM.

Any ideas please?????

DD
1990 DoKa Syncro 1.9AAZ


Imagination is more important than knowledge.

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HarryMann
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Re: AAZ - Erratic Tick Over

Post by HarryMann »

What pump? AAZ?
check cold start lever on engine side of pump is backed off.
Possible idle stop problem but also possible internal pump.problem.
Check freedom of all return coil springs and fuel.lever.
Pull cold start lever on pump right back.
Possoble over fuelling if someones been a messin with main fuel screw.

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Oldiebut goodie
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Re: AAZ - Erratic Tick Over

Post by Oldiebut goodie »

The mechanism must be fitted otherwise fuel will be p***ing out of the shaft!
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1̶Y̶ ̶1̶9̶8̶7̶ ̶H̶i̶-̶t̶o̶p̶ ̶C̶a̶r̶a̶v̶e̶l̶l̶e̶
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