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2.1 DJ rebuild and diagnosis.
Posted: 24 Oct 2008, 19:30
by amazingdave
Hiya,
I've bought a 2.1 DJ to replace my DG.
The DJ was showing white smoke before I got hold of it, and I want to rebuild it.
Should I just take it apart and replace all worn parts, or should I attempt a diagnosis before I dismantle it? How much diagnosis can I get with it sat on the bench?
The oil is clean, and that's as much as I can say.....
Dave
Re: 2.1 DJ rebuild and diagnosis.
Posted: 24 Oct 2008, 20:37
by Mr Bean
amazingdave wrote:Hiya,
I've bought a 2.1 DJ to replace my DG.
The DJ was showing white smoke before I got hold of it, and I want to rebuild it.
Should I just take it apart and replace all worn parts, or should I attempt a diagnosis before I dismantle it? How much diagnosis can I get with it sat on the bench?
The oil is clean, and that's as much as I can say.....
Dave
For a full diagnosis you need the engine in the vehicle preferably mobile. However you can do a compression test on the bench if you fit a starter and this will highlight shot pistons, bad valves or maybe a head gasket. I personally would feel confident in spinning it over just a few times without filling it with oil. Although valves have to be pretty bad to make smoke other than on the overun due to worn guides. Unless it is a recent rebuild once you start to dismantle it you are almost certainly going to want to refurbish as you re-assemble and even the cost of gaskets and seals will make this significant in terms of cost. Its a toss up really although others will be heavily biased one way or the other. They will soon pop up and give their opinion!
Cheers
Smiffy
Posted: 24 Oct 2008, 20:59
by amazingdave
How much am I looking at for the standard refurb bits and bobs?
The chap I got the engine off said it smoked white when he first installed it, with the smoke clearing after a while. The smoke came back when he reved it though.... Rings?
He gave up on it there and then and got a diesel instead.
I don't mind spending a bit to rebuild it properly. But I'd like to do it myself.
Dave
Posted: 24 Oct 2008, 21:03
by HarryMann
White smoke you say?
Coolant, typical head seals maybe?
You either pop the heads off and just do them if that's what it looks like and go with that or take the whole thing apart.. I'd go the first route, if it ran OK otherwise before but of course take a good oook at the bores and state of the piston tops and land, look for the extent of the step etc.
I would however check the crankshaft end-float is within tolerance, and maybe fit a water & oil pump, maybe...
To check the bottom end its a strip-down...
Posted: 24 Oct 2008, 21:13
by SkinupCamper
If its a refurb then dont worry.....keep going till you find the problem, if its white smoke the problem will show it self to you.....prove your fault!
Posted: 24 Oct 2008, 22:27
by Red Westie
The spark plugs are a good initial guide to isolating the problem to one or more cylinders. Once the heads are removed the carbon build up and appearance of the combustion chambers/piston tops give similar direction in your diagnosis.
Martin
Posted: 24 Oct 2008, 23:09
by Ian Hulley
Ian Hulley wrote:[If it helps I've just ordered the following for our 2.1DJ rebuild :-
Camshaft £49.90
" Bearings £4.95
Crankshaft £240.84
" Bearings £37.89
Big End " £6.94
Dizzy Drive Collar £ 16.81
2.1 Piston Rings £44.59
Engine rebuild Gasket Set £73.51
Oil Cooler £46.95
" Pump £12.50
" " Cover £3.95
With carriage all-together £568
The pistons and barrels (£240 ish/set) , pushrods and tubes were fine and will be re-used. The crankshaft will be reground to be used in the rebuild of the 1.9DG to a DJ next winter.
The reason I got a new DJ crank was a) someone else is paying for it and b) while new ones are still available.
Ian.
From a previous post
Hope this helps,
Ian.
Posted: 25 Oct 2008, 01:06
by HarryMann
I'm sure that'll be of acute interest to Dave, Ian...
Things really add-up don't they, once you start...
Out of interest, what are you doing about the con-rod big-end bolts...
Replacing them all?
Posted: 25 Oct 2008, 05:59
by amazingdave
Hopefully the crankshaft won't need replacing!
Unfortunately I'm just going on heresay for the condition of the engine so I will probably go all the way to the bearings.
It would be a shame to eradicate the white smoke with a new head gasket just to find that the big ends/ main bearings are shot.
Thanks for the pricelist Ian, it at least gives me an idea. Incidentally where did you buy your bits?
Thanks
Dave
Posted: 25 Oct 2008, 11:46
by wasserleaker
Ian Hulley wrote:
If it helps I've just ordered the following for our 2.1DJ rebuild :-
Camshaft £49.90
where is this from, Ian?? my new DJ camshaft with timing gear was 230 quid from VW, is it a second hand, or a regrind?
Posted: 25 Oct 2008, 14:58
by Ian Hulley
where is this from, Ian?? my new DJ camshaft with timing gear was 230 quid from VW, is it a second hand, or a regrind?
The camshaft is new from Volkspares
Out of interest, what are you doing about the con-rod big-end bolts... Replacing them all?
I plan to re-use the big-end bolts and nuts ... they're 2.1 and I'm lead to believe re-usable. As I said in the list the pistons and barrels are fine.
Ian.
Posted: 25 Oct 2008, 15:32
by wasserleaker
Apparently, it's the 1.9 big end bolts that are re usable if you can get some of those, my 2.1 had stretch bolts which it's not a good idea to re-use, they were expensive from VW but as i was doing a proper job, worth it, i thought. also, a new cam will need new hydr. lifters too, major skimp to re-use the old ones

Posted: 25 Oct 2008, 16:01
by HarryMann
Mmm.. opinions I've heard suggest, amongst ovalling of the shells, distortion of the caps, and crank end-play, that the 2.1 bolts might also be one reason for this sort of thing being far from uncommon...
https://club8090.co.uk/wiki/Pe ... wing_a_rod
Posted: 25 Oct 2008, 16:14
by Ian Hulley
The engine I've dismantled was suffering from endfloat due to a knackered pulley keyway but the oil issues resulted in the mains failing ... there was no other damage, the camshaft and bearings were very worn and the bigends were also very worn ... it would seem prudent to replace the camsaft, crankshaft (cos I could get a new one and have the other reground for my DG rebuild) and all bearings. The oil cooler is also being replaed and the hyd. tappets cleared out and re-primed
Ian.
Posted: 26 Oct 2008, 12:16
by wasserleaker
does anywhere do oversize shells for a reground crank? couldn't find anywhere when i was looking into parts for a rebuild, but in the end the journals measured up ok so i used std ones, just wondered.