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sudman · Posted: Wed May 14, 2003 4:41 am Post subject: runnig REALLY rough

Hey, I own a 1983 Sud Ti thats running a 33 1.7 8v hydraulic tappet motor. The thing ill not run on four cylinders. The carbs have been balanced and the mixtures set correctly, the ignition seems fine, (plenty of spark) and its got new plugs. I was told by a mechanic that it may have a crook hydraulic tappet(s) which is causing the problems, or that it may have a worn camshaft. Tried additive - no success, have changed to a thinner oil, also with no joy. The car starts on 4, but then cuts to 3 cyls (or less) when cruisings revs are reached. Has anyone else had any experience with a hydraulic 1.7? Any help would be greatly appreciated.

Cheers

sudman · Posted: Fri May 16, 2003 1:44 am Post subject:

Anyone??? This problem is really frustrating me Mad

. If anyone can advise of anything I can try before I pull the heads off it'd be excellent.

Cheers

ricardo · Posted: Fri May 16, 2003 5:31 am Post subject:

if it is getting 4 cly on trottle but only 3 on idle or cruse then most likley just a block in ya idle jet
on idle ,pull the leads of the dist cap one by one and see which cyl ase doing some work and which one makes no change
most unlikly that it is a tappet fault
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Gary UK · Posted: Sat May 17, 2003 11:21 am Post subject:

if you are loosing the right hand bank it may well be your fuel supply (fucked pump), as the left carb (sitting in car) gets the fuel first . If it's running lumpy take the leads off the right if it doesn't affect the running remove the plugs on the right and smell the mixture. It will acually make the car run better taking a plug out of a cylinder that's starved of fuel.

Matt C · Posted: Sat May 17, 2003 3:27 pm Post subject:

The Idle circuit of a carbi only works at idle, when the throttlr plate is closed. As throttle plate is opened the transition ports are uncovered and begin to operate. after that the main jet does all the work.
So at cruising speed it's the main jet that is working, the idle circuit does not function as there is no depression where he idle port is. The carbi only operstes using the venturi at this point.
As Gary stated, you need to pin-point which cylinder is shutting down, and what exact RPM it's doing it.
If it was a tappet you would certainly hear a distict loud "Tapping" noise.
You really need to be more specific, does it drop a cylinder when you rev the engine when stationary or does it only do it under load?
Sounds like it could be a HT lead (high tension lead) or an electrical problem. Have you checked your distributor cap?
If it was a fuel pump issue you would not obtain any high rpm under load.
It's hard to say, you really need to find which cylinder is doing it and go from there.
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ricardo · Posted: Mon May 19, 2003 4:00 am Post subject: fuel lines

just had a thought...
check your fuel lines each line into the cards should go into the lower connection on each carb
if your r/h carb feed , coming from the L carb goes into the return pipe ,this can lead to fuel starvation on the r carb whilst cruzin
get im touch sudman ....whoever you are ??
_________________
alfa romeo trofeo series new zealand, video site .
http://alfa-racing.blip.tv/

alfatrofeo blog and interesting stuff .... unofficial ....
http://alfatrofeo.blogspot.com/

sudman · Posted: Mon May 19, 2003 4:45 am Post subject:

Cheers for the tips guys.......

Tomorrow is my day off uni so I'll give a few of these things a whirl, and I'm gonna borrow an air compressor to try clear these idle jets first.

It is the right hand bank that appears to be the problem, cyl. 3 to be exact, as when I take the plug lead off that cyl. it doesn't make any difference to the running.

As for exact rpm and whatever, the car just seems to drop off at varying points, ie. if its left idling for around ten minutes or so it'l drop onto 3 and sound real lumpy, its just that when it's under load it's more noticeable (car shakes) like its misfiring. Also backfires lots a cruising revs, this should be an indication it's getting fuel right?

I'll try a new dizzy cap, cos the one on it I suspect is still the original one from the 1.5, which means its already done around 200,000 km, so it could probably do with one anyway.

I'll let you all know what happens in a couple of days,

Thanks again.......

Richard (sudman)

PS. University students and old Alfas??? not the best combination I suppose, but oh well it beats driving round in an old Corolla or something!

Gary UK · Posted: Mon May 19, 2003 5:07 pm Post subject:

If the fuel lines are round the right way then I recon it's the fuel pump as you are describing the symptoms. Take both the plug leads off the right hand side and see.

sudman · Posted: Tue May 20, 2003 3:04 am Post subject:

Hello again,

Replaced dizzy cap and rotor..... no success, also gave the carbs a good going over with the compressor & blower gun, also with no joy. Fuel pump seems to be doing its job.... lotsa fuel comes out when u disconnect the lines and crank the engine over.

Spoke to another mechanic today also.... he concluded it could be a worn camshaft as well.

Cheers,
Richard

Matt C · Posted: Tue May 20, 2003 9:30 am Post subject:

ermm
take off your tappet cover and have a look!
or is it the cam assembly type unit?
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bvolden · Posted: Tue May 20, 2003 9:54 am Post subject:

I have a simmilar problem, but mine only runs on three when idling. When I put the power down it runs okay. A friend of mine said it was because of my cams (which aren't original).
By the way, how much fuel are the 33 supposed to drink? Mine's a bit thirsty at approx 1 litre per 10 kilometeres. Confused

Any opinions?

Gary UK · Posted: Tue May 20, 2003 10:46 am Post subject:

The fuel pump can run intermittently and appear to work fine you want to check the supply when you are having the problems (even then it might 'appear' to work disconnected as the pressure is lower, check the pressure of the fuel supply with a pressure gauge). My pump played up for 2K (I didn't at the time know it was the pump) till finally going.

When it is playing up take the filter out and spray damp start into the right carb and see if this makes it run better.

ak8635 · Alfasud Joined: 16 Apr 2003 Posts: 38 Location: London, UK

mine is doing about 10km per litre also .
(however i am mostly driving on motorways 80-90mph and not in city).
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