[Lewis Partington]

Hi I have a 1995 T4 1.9d non turbo, I bought her about a month ago. When I bought her she had some smoke on initial start up but this would clear on the way back from the MOT she shredded the aux belt which in turn knocked the timing out. Any whey new belts fitted and retimed and she starts great and sounds fine, however we have just been on a 1000 mile round trip to Newquey and we noticed heavy black/blue smoke under load ie up the many hills they have down there. Checked the oil and she had used 1L of oil on the way down and a further 2L on the remaining 650 miles back to home.

My question is this, I believe is could be a number of things, rings, valve seals or bent valve. I wanted to try and rule out rings by doing a compression test but if I have a bent valve (due to the timing slip) will a compression test still work?

Or am I looking in the wrong place completely ie timing still off?

Any help is appreciated.

 

[JonCa]

.......... Any whey new belts fitted and retimed and she starts great and sounds fine,
................. My question is this, I believe is could be a number of things, rings, valve seals or bent valve. I wanted to try and rule out rings by doing a compression test but if I have a bent valve (due to the timing slip) will a compression test still work?
........

You say its starting and sounding fine so I'd find it unlikely that you have a bent valve that would cause issues in doing a compression test.

The oil usage is consistent at about 1 litre per 330 ish miles, on the heavy side but.....
black smoke typically unburnt / badly burnt fuel so possible fuel pump not set up quite right but it is only a small engine working very hard.
Also possibility that injectors are past their prime and not vaporising the fuel the way they did when new.

 

[Lewis Partington]

Forgot to add she has done 200000

 

[JonCa]

Sounds like it could well be the time for some serious loving care. BUT I'd test it first.

You could simply take it in for a rebore new rings etc however I think there will be many who would recommend an upgrade to a 1.9tdi (ex Golf or similar) all depends on what you can do and who you can find if you dont want to do the work yourself.
Plenty of threads on here describing due process.

 

[Lewis Partington]

Ive looked at the TDi conversion, I can do the mechanicals but the electrics scare me to death! Also with my engine I would need parts of a TD to start with.

 

[rudis_dad]

I'd agree that the fuel pump timing may not be on after the belt replacement. Black smoke would suggest over-fueling, or it could be indicative of poor fuel spray pattern (so not igniting properly) caused by worn/blocked injectors, or blocked fuel filter. It's also possible that the EGR and/or the inlet manifold is coked up. Pretty simple job to remove/blank the EGR and remove the manifold to clear it out. You might also consider getting it Terracleaned.

Blue/grey smoke is more consistent with excessive oil use. Three litres in 1000 miles sounds fairly heavy to me - I do 5000 miles between changes and usually get out a good 2/3 of what I put in, and it leaks as well! So consider worn bores/rings as you say, valve guides (is it rattly at startup? Sure sign).

A compression test will only show if compression is down, it won't show the cause, which could be many - e.g. worn/damaged valve heads and seats, blown head gasket, cracked head, holed piston, worn rings/bores, etc.

 

[Lewis Partington]

She starts up well every time I don't even use the cold start pull (again could this be a pointer towards over fuelling). After the belt change/timing slip I have noticed that she is a little tappy. I have heard that you can advance/retard the timing at the pump but looking at the bolts holding the pump on it seems to be fixed? I don't think I have an EGR valve on mine being a straight 1.9d. Just to add she only smokes on hills or under load, just ticking along on the motorway at 65 no smoke.