Loss of Power

[D87 SMW]

1989 Maestro 1.3

Replacement engine recently installed and running. Has been stood for a couple of years, beforehand.

Has now been tuned to run evenly and at a good idle.

The choke now operates correctly: I wondered why the revs weren't increasing when on (manual) choke... The choke arm which raises the idle speed (accelerator arm) wasn't touching and wasn't anywhere even near.

The problem with it now is that when you accelerate, there is a distinct lack of power and it seems as if it's choking on air or something. This is where I'm stuck. All the hoses etc. are OK. Perhaps the mixture is still too much air:fuel?

I don't know where to go with this, has anyone any ideas?

TIA.

[D87 SMW]

Well I've swapped the plugs from my '96 Maestro and taken the screwdriver from my dad and managed to get it running a bit better.

It is still fairly reluctant to rev for some reason. Where my LHD will rev freely at the slightest press of the pedal, 'GGT seems very slow on the uptake.

I'm shoving some Redex in it and will try an 'Italian tune-up' to see if that helps any. Perhaps it's just a bit coked up? Lord knows, Winehouse can't perform that way either...

[countrydude]

If the new engine is lower milage with the added benefit of standing for 2 years a certain 'tightness' could be an issue. With higher milage and everything being well worn in the engine will turnover with less resistance. It sounds like the carb could do with a little tweak? I wouldn't go too crazy on the italian tune up!! They work best with diesel engines, with small petrol engines the effects can be ....

Is the exhaust manifold good and clear?

[PhilD]

Have you checked that there is oil in the carburettor dashpot damper. If there is not and you attempt to open the throttle , the carburettor piston rises rapidly, which results in a sudden increase in air to the engine (effectively weakening the mixture) and could cause the symptoms you describe. Hope this helps.

[D87 SMW]

Thanks, yes the manifold is clear we have fitted everything with new gaskets etc.

There is oil in the dashpot, I made this suggestion today, too.

[E_T_V]

Most likely is that the linkage gaps on the carb are set wrong and thus the carb is running out of tune. i.e. tuned ok for idle but probably leans out or runs too rich on acceleration.

good tune up would be my first advice.

[countrydude]

I think after a few hundred miles you will begin to see a difference.

[PhilD]

One more thought - have you checked the ignition timing? I think that this would show as lack of power if it was a long way out, but I would also have expected that it might make the engine difficult to start and show other symptoms such as pinking under load if that were the case.

[SimonR]

Steve,

Have you checked the vacuum pipes? If you had leakage then I'd expect this sort of thing to happen.

SR.

[D87 SMW]

Steve,

Have you checked the vacuum pipes? If you had leakage then I'd expect this sort of thing to happen.

SR.

Yeah, as stated, they all seem fine. I'll go over it again, though.

[G Force]

Hi Steve, Sounds like the ignition timing is retarded to me, What did you set it to?

Gary:)

[Ricky]

If it's any help, I encountered this problem on a mate's Volkswagen Scirocco (well, it's got the same gearbox! :laugh: ), and we played with the timing, which helped a little, and then I stripped the carb down and rebuilt it (even though it was a brand new Weber replacement), all to no avail..... In the end, it transpired the cam timing was three teeth out on the belt, and the pistons were nearly hitting the valves! After the belt was done it all behaved itself remarkably well, thankfully...