Overcharging 21 1.9 diesel

[nudger2802]

Hi Folks, I got a problem with my 1994 21 1.9 Diesel (F8Q). Occasionally it overcharges the battery and the stereo will die, the rev counter jump all over the place and I loose engine power.

I have changed the alternator for a brand new one which makes the problem worse and tried cleaning the terminals on the old alternator which seemed to help a bit but its back again now.

I have stripped the origional alternator and cleaned all the bearings the comutator and the brushes and all the terminals and as i say it made things a little better but not much.

I have wired my cooling fans up to a switch on the dash ages ago long before any problems started as there is a break in the wiring somewhere so they dont work off the o.e. switch but, and this seems a little strange to me, when i switch the fans on and leave them on I dont get the problem.

The only thing I can think that links all these components (alternator, cooling fans, stop solenoid, ignition switched feed) together is the pre heat box (glow plug relay unit) and before i search the world trying to find a good replacememnt was wondering if anyone else has ever had a similar problem and found the glow plug relay to be at fault?

Any suggestions would really be appreciated?

Many thanks,

Nudger

 

[Chris H]

with it working ok on load means theres a fault or short somewhere. I have a similar issue with my grey car it affects the tacho. With it idling the tacho will move about all over the place then when the interior fan or headlights are on it behaves.

Anyway i would say your probably right about the glowplug relay being the main cause other than faulty wiring.

 

[The T.I.B.]

Had the same but it was a petrol car and replacing the alternator sorted it out... good luck with yours

 

[nudger2802]

Cheers for that. The only thing I can think to try is another glow plug relay then if I can get hold of one and see if it makes any difference. Might check the fan wiring for continuity too and see where that gets me. Oh the joys of electrical niggles Least it aint the normail Italian crap wiring I am used too workin with lol.

 

[PhilA]

with it working ok on load means theres a fault or short somewhere. I have a similar issue with my grey car it affects the tacho. With it idling the tacho will move about all over the place then when the interior fan or headlights are on it behaves.

Anyway i would say your probably right about the glowplug relay being the main cause other than faulty wiring.

In my experience usually a bad ground. Check the engine strap, caused allsorts of hell on my Fiat when it was almost broken through and working on the last few strands of corroded wire... the electrics wanted to go elsewhere- turning the ancillaries on would give the current a route to ground and everything would behave- bit like if you've ever seen a mk3 Escort's rear lights where the ground's gone fusty... brake and indicate at the same time and you've got your very own discotheque lighting...

--Phil

 

[nudger2802]

That was the first place I tried and every earth in the engine bay has now been cleaned up and if need be replaced all to no avail Owned and fixed the rear lights on many an escort so I know where your comin from with that one, I love Fords bur damn the escort boot seals were shite lol Tryin to get hold of one of these pre heat boxes (glow plug relay) second hand is bloody hard work. They are the same on s mk1 clio or a 19 diesel but there just aint none out there Strugglin with the continuity tests as its an intermittent fault oh well keep batlin on.