T25 tickover problem.

[bloggs]

Hi guys, I am new to the forum, but not new to VW's

I have a mk4 golf and bought my son and daughter mk4 golfs as well
My dad has had VW vans for 40 yrs and wouldnt have anything else. I have now inheritted his van, a 1984 1.9 DG panel van with 48k miles only. He only used it for camping in.

Since he stopped driving it has been stood for about 4 yrs but the engine run weekly. I now use it daily. I have had a number of thing to do to get it right, like brakes, fuel pump, vacuum advance, coil, leads, cap, rotor and plugs.
The exhaust box is stainless but the studs are mild steel and rotted away, It also cracked, so I have welded it and retapped the studs. That was a pain!.
Anyway I digress. I have a few outstanding problems which I hope you can help me with:
I can't find any details of how to set the timing up, what I have found talks about digital advance, but I don't believe I have that on this engine. I Have set it to 12 degrees before, and it runs well. However it can go for days running absolutly perfectly smooth and powerful, then suddenly it wont tick over, as soon as I take my foot off it stalls. It will start straight away but only runs if I keep my foot on the pedal at higher revs. It is missing a bit or not as smooth when like this. It does rev and pull, possibly not as well. then a day or so later will go back to perfect again. I cant see anything wrong, and the choke is not sticking. I stripped the carb and it seemed clean, but I didnt have access to compressed air to blow out the jets at the time.

Also it has a new battery, but the alternator is charging at 13.8volts which seems low. I stripped the alternator, and other than putting new bearings in it, the rectifiers are OK and the regulator works to the voltage stamped on it at 14v ish. The engine sometimes does seem to turn over slowly. I did use a ajump lead to link the engine to the body in case the earth was poor but it didn't make any difference to either of the these faults.
Any help would be appreciated. Thanks.

[Ian Hulley]

Hiya, welcome to the forum, nice looking van

On plain old unleaded petrol the timing should be 4 degrees before TDC with the vacuum advance disconnected. TDC is the U notch on the crank pulley aligned with the split in the crankcase and as a rough guide to set-up there is also a timing mark on the inside of the dizzy body.

You should check the fuel filter on the outlet of the tank on the offside (make sure there are no others 'cunningly' placed in line as well ) and also there is a cone filter inside the inlet spigot on the Pierburg carb ... this is the last resort filter and quite often gets ignored.

The slow turning over ... there is an oilite bush in the bellhousing which supports the armature shaft of the starter motor, these wear and cause the starter to stick ... they cost a pound or so but can be a bugger to get in/out. Soak the new one in engine oil overnight before fitting

Hope this helps, Ian.

[bloggs]

Thanks Ian, Thats a great help.
I'll swap the filter anyway, its been there years, and I'll check the carb filter, I guess the bush in the bell housing can be accessed and removed with the engine and box in situ. If its cheap I'll just do it anyway.

[Oldiebut goodie]

As for the 13.8v output - replace the regulator with this one (assuming that you have a Bosch one) http://www.ebay.co.uk/itm/250740800329? ... 1439.l2649 it brought mine up from the same 13.8v to 14.3v - I didn't like the lower voltage either and mine was a new alternator.

[bloggs]

Yes it is a Bosch alternator, and that is physically the right regulator. I'll do that as well. Thank you.

[ed_the_robot]

A 12 mm tap works well for removing the starter bush, and I found freezing the new one before carefully tapping it home on the end of a nut and bolt did the trick