Whats that power loss thinggy again?

[Meekcome]

Hello helpful peeps

Me again, only contributing when I need something

I've owned my 1098cc traveller since age 17 (20 years) but the days of daily use are passed. Wasn't always the way - have MOT papers showing I covered 26,500 miles one year - and replaced worn king pins at both tests due to enthusiastic conering style . Nowadays just grind company eurobox into the ground while Morris relaxes in garage and I slowly forget just about everything I learned at the kerbside from me' Dad.

So, can you please save me telephoning him again? ...the old girl has just developed a dimly familiar power loss habit under acceleration and at higher rev range. It gets worse if you press the gas but have managed to coax home by keeping revs down.

Thought I remembered something about voltage regulator points corroding, so gently rubbed down with wet-n-dry but test tonight showed to no avail. Trying to avoid expensive elemination exercise working gradually through replacement of all inginition components...any hints?
Electrical/fuel?

Thanks for reading....

[Onne]

Have checked the airfilter? Is that still clean?
Is the carb clean?
Are the points set up right?

My bet wouldn't be the voltage regulator

[Onne]

Also moved this to mechanical, so it gets noticed

[simmitc]

Possibly fuel starvation - check delivery from pump, check air vent to tank, check that there isn't any muck blocking the jet in the carb. As noted above, check air filter. I've also seen this symptom with a condenser that's on the way out, so try changing that.

[minor_hickup]

Is it a flat spot? Has the dashpot got enough oil in it?

[bmcecosse]

Sounds like distributer problems to me - mechanical advance mechanism not working/seized and probably the vacuum advance is knackered too. Even if you renew everything on the ignition side - including the vac advance unit - it won't cost £50 and that's it fixed for another 20 years!

[Meekcome]

Hi again

Following helpful tips I re-set the points, checked condition of plugs etc and went for enthusiastic run (circa 5 mile)during which old gal performed fine - even when I tried to provoke the problem wioth high revs, hard acceleration.

Returned home, swithed off for an hour - declared 'all well', loaded up the family and within 100 yds of the house the power-loss returned. To vbe clear s not a fractional drop in power, such as the feeling of a single plug giving-up - it's a complete falter, prolonged by use of the gas pedal - but letting off and very gently feathering the accelerator permits a crawl home - upto say 20-30mph.

This morning thought I'd re-test prior to changing the ignition components and found a completely flat battery - no iginition light and no amps showing on multimeter.

Question in my mind and to group wisdom - is this sympton or cause? Would a deteriorating battery cause such power-loss in fits and starts? Certainly its always been eager to turn-over till today. Alternatively which other components if failing would result the flat battery - dynamo?

PS> As an aside - where is the tank breather I was recommended to check? Is it solely in the lid of the filler cap?

Thanks again gang.

JJ

[bmcecosse]

The flat battery may have been caused by you 'cleaning' the voltage regulator points, or did you leave soemthing on by mistake? With recharge - is it now ok? The 90% power loss - could be many things - but fuel starvation must be high on the list. Could also be sticking piston in carb - or just needing a spot of oil in the dashpot.

[paulhumphries]

I once had a Hillman Imp with starting problems.
Turned out the inlet manifold was loose.
Might be worth a quick check to ensure your manifold and carb nuts are still tight and not allowing air in to upset the mixture.
Also with my A35 a faulty batch of silencers with too small holes in the internal perforations took ages to solve lack of power due to excess back pressure.
A Capri stopped running one day and nothing would ge it started. Long story but in the end despite removing the distributor and dismantling / cleaning twice that was the soucre. I didn't remove the earth tag from the distributor body - and it was corroded underneath causing it to still create a spark when checked visually but corrosion created resistance so that not enough when inside an engine to fire up.
What I'm saying is that it can be silly things that you say to yourself "if cann't be that" (because you've checked it before or replaced with new) and don't dismiss those areas unless you are 110% sure they are perfect.
The little bit of corrosion on the Capri cost me over £300 in parts after I was missinformed (by AA who couldn't get it running either) that the carb was faulty.

Paul Humphries

[simmitc]

A sticking dashpot in the carb is a very good suggestion, I've seen that before too. The air vent is purely in the fuel cap.

[pskipper]

Considering the weather it's worth checking the HT leads which when old can cause between 75-90% power loss especially in wet weather due to arcing. (Wait till it's dark, make sure she's not under a street lamp start her and pop the bonnet, if there are sparks jumping between the leads this is part or all of the problem)

[callyspoy]

as i seem to have an almost identical problem, where should you fill the dashpot to? its infuriating this problem! and as with meekcome it seems that it is working fine..then...it just dies when you try and rev a little bit higher than normal!

[bmcecosse]

Black (or brass) nut shaped knob on top of the aluminium 'bell' (actually dashpot) of the carb. Unscrew - add small amount of oil - refit. Finger tight is sufficient.

[Kevin]

where should you fill the dashpot to?

To the shoulder you can see inside.

[bobbins]

it must be the time of year or something, but my 1275 is having exactly the same problem. She runs fine when you don't apply much pressure to the throttle, but as soon as you try to accelerate, the power just disappears...

Anyway, after Roger's quite successful rolling road experience near Southam, I thought I would take mine to the same place and see what they had to say on the subject...

Funny thing is, the manifold gasket was changed on the MOT to France trip this year, so I will check looseness on that too as she starts like a dog with whooping cough!!

[bmcecosse]

Try a new set of plugs befoe doing anything else!

[callyspoy]

i tried the plugs from my dads...the weird thing is, my dad and i removed the engine from his car, and put it in mine the same day...so i'm confused as to why it didn't work, as it worked PERFECTLY in his...aaaaah! so close to putting the 803 back in!

[downsey]

low dashpot oil is my guess

[callyspoy]

i topped it up

[bmcecosse]

Did you transplant the COMPLETE engine unit ? What parts have not moved over with the engine ?