Knock....Knock...Who's there?....Trouble!!!!

[KarlT]

Hi All

Here we have a 87' 2.1 (112bhp) digifant (I think) engine.

Only had it a few months but it sounded good, went good & had excellent compression readings.

Its had a new exhaust, new proper three prong plugs and oil.

Then a few days ago I noticed it sounding a bit rough, the next day it was really noticeable.

There is a real knock knock from the near side of the engine cylinders (3&4). Engine really rocks about like an old diesel on tick-over. It still revs up and seems to smooth out a bit but still doesn't sound right.

Its sounds a bit like really loose tappet only more substantial.

Investigating this lead to my other question/puzzle....

I thought I'd check the timing, reading Haynes it says being a DJ Digifant you need to disconnect this & that & the other which I did.

Start the engine then disconnect the blue connector for water temp, on doing this the engine revs away at around 2500/3000 rpm.

How are you supposed to check the timing when it should be ticking over at around 800 rpm?

Please don't let it be terminal.

I think this tuning lark is abit advanced (no pun) for me, any really good garages here in S Devon who know what their doing?

Aircooled was sooo easy....maybe all is forgiven

[Ye Olde Syncrospares]

2.1 dj -digijet, 2.1 mv,ss digifant,follow timing directions as per book,dont worry about tappety noises too much as itll go away on a longish drive,doo worry if it sounds a bit deeper,cj.

[KarlT]

Hi CJ

Thanks for repling.

It definitely sounds like it is coming from the n/s heads
but it is a deep tick...tick...tick sound. And the engine really rocks around.

I have been doing lots of short 2-4 mile trips lately

[syncroand101]

Like CJ says, it is more than likely just a tappet, a really bad one can sound like death.

What oil was used at the change?

Try take it for a longer blast and see if that helps it...

[KarlT]

Ahh you guys.... You're cheering me up

Any more thoughts on the blue connector & the engine reving up?

As to the oil....I don't know the pre-owner had just changed it for the sale so I haven't re-done it .....Maybe I should?

[HarryMann]

Pretty sure you don't disconnect the T2 sender to do the timing - thats what you seem to be doing and it won't like it as it has to know what the temperature is.. are you confusing that with something else, maybe the ISU plugs (join together)

As above says, take it on a really long run to get that hydraulic tappet pumped up. Its either drained down or some muck has been loosened in the engine - did you flush it by any chance. Is the oil black again already?

Possible one of the new plugs is duff, or you've not got a good set of leads, if ts rocking about badly - if it was OK before, then, new plugs and somethings been upset? But 1st a long run, see if it pulls OK, quietens and smooths down, Ok

[KarlT]

Cheers everyone

I'm a happy chap again......Ran it out to Sainsburys and back

Its sounding sweet again, treated the old boy to some super 97*

As for the blue connector & reving away I made a terrible mistake of mixing my digi's.....Digifant= remove sensor
Digijet = do not remove sensor

Only 6 hrs wasted but you live and learn

Thanks again

[stuckin88]

Dont use synthetic or semi synth. in these engines-tends to cause tappet rattle--use mineral oil-most use Quantum 15/40 from your local GSF--you can also buy Mann oil filters from there as well- indentical to genuine VW & half the price--apparently it is inadvisable to use some other makes of filter--

[ozzy]

My 1.9dg rattles sometimes really loud the first time it happened i sh.1t myself but after ten miles its ok