2.1 cylinder head cracks

[boyroy]

Hi. Have just removed cylinder heads from my 1989 2.1 engine. Fuel injection and LPG.
I have cracks between the valve seatings. Could you tell me what is a likely cause and what could be a remedy for this.
Is a secondhand head about. I have heard of a company that weld repairs and remachine the head. Should I fit hard valve inserts whilst dismantled. Do I in future run on 98 octane unleaded. Any help is welcomed.
Also what is the Bentley manual and how do I get this manual or any other worthwhile books on the T25 as I am a newcomer to these vehicles.i have just purchased this vehicle and told that it was a new engine 9000 miles only and the misfire was that it needed setting up????
Regards Boyroy.

[itchyfeet]

small cracks are common and not a problem unless they get deep.

my Dg ( same heads) cracked through to the water channels but a you can see from the pics in the 2nd link below the water chanells are a long way back.

http://www.brick-yard.co.uk/forum/rusty ... 43480.html" onclick="window.open(this.href);return false;

https://club8090.co.uk/forum/viewtopic.php?f=37&t=118129" onclick="window.open(this.href);return false;

Bentley is a USA manual which you can get new or second hand on ebay often.

callen vangon in USA so search on 'volkswagen vangon bentley'

get a haynes also you can never have too many manuals

[Wychall]

Bentley manual e-book available here.
https://club8090.co.uk/forum/viewtopic.php?f=7&t=110469
For members only............

[thebobster]

The 2.1 DJ engine is high compression and should be fed 98 ron petrol when not using LPG.

[boyroy]

Hi. Many thanks for your help on this. The reason for finally taking the engine out was the irregular running. New plugs, New cap. New leads. Ignition seems fine. Compression test showed lower on the left side pots. After taking off the heads and seeing the cracks I thought I had discovered the problem. I have yet to take out the valves.
The engine when running has very strong acrid smelling exhaust but not smoking. The fumes are very bad. But it starts ok.
My next thought goes to injectors and if its excess fuel on the left bank of pots.
Once again I am grateful for your help and would welcome all the help I can get.
At the moment I feel I may have bought a lot of expensive problems that the previous owner was not very forthcoming about.
Kind regards and thanks.
Boyroy

[itchyfeet]

low compression can just be poor valve seats, take them out and grind them in but while your at it have a close look to see if the crack extends behind the seat or if the valve stem guides are eaten away, or if any of the ports are particularly clean.

Acrid smell could be coolant burning off, mine had a strange smell when it got bad but if it's cracked to the waterways you would expect to use a little coolant and when it starts to get bad I got a puff of steam when starting hot, i.e. after stopping to refuel.

I had quite good compressions even with the crack.

it's a balance between the cost of a new head and the cost of doing it again including your time if indeed it is the problem.

[mark]

when I bought my dj it had a mystery misfire and over fuelling issues, what I started with was a replacement of all the service items (plugs, leads etc) and had no luck, new temp2 sender stopped the over fuelling as did cleaning and remaking of all the electrical contacts inc earths, also a strip down of the amf and gave it a good blast of contact cleaner. haypresto ticking over and power right through the range, but under load it would do what felt like a miss fire between 25mph and 35 mph this led to the buying of a box of nice spares that are gathering dust and no doubt value in my garage..............the problem was an oval shaped tyre at the rear.

fuel wise I run mine set at factory timing on 98/97ron unleaded. If its been sat for a while the fuel will have gone off. the 2.1dj's hate low octane fuel and will kick and buck their disapproval of cheap fuel. we're going to france this summer where (if the tinternet is to be believed) I will be running on 4star leaded and see what improvements if any that brings

mark

[Martin]

the acrid smell when running will be coolant, sounds like a gasket failure, or coolant leaking around head studs
or lower barrel seal leaking.
check heads very closely for pin holes or pitting around barrel seals.

[boyroy]

Hi. Thanks for all your help everyone you are restoring my faith in people and helping me to realise a T25 is worthwhile.

I have done research and found an engineering workshop who are going to replace the valve seats with a hard type.
Whilst the old ones are out will weld the cracks and re machine the head. also replace the worn valve guides.
Should anyone else need this company copy this down for future; DAMICO Engines Ltd. Unit 18. Roudham Park Industrial Estate. East Harling. Norfolk. NR16 2SN. Tel 01953 717784. You never know who you need in life.
Hope this will help. Regards Boyroy.

[kevtherev]

Vlave seats are already hard.. Just a regrind will sort that out

[itchyfeet]

How much do they charge for that head refurb service?

[boyroy]

Hi. For both heads to be sorted he reckoned around 150 to 175 pounds labour. However I will be in a better position to say when I get them back with the final bill. A second hand 2.1 head is very rare so I have no choice and feel very lucky to be able to get them done properly and as good as new. The final bill with seats and guides and valves around 350.00 I guess.
Hope this helps. Boyroy.

[itchyfeet]

Surely 2.1 and 1.9 dg heads are the same and dg heads are not so rare second hand
Second hand may not be much better than yours though
Probably best not to let them skim the water jacket sealing surface unless they skim the liner seal surface by the same ammount

[AdrianC]

the 2.1dj's hate low octane fuel and will kick and buck their disapproval of cheap fuel.

Yours might, but our DJ runs quite happily on 95 - no pinking, no kicking or bucking either. Given how few times we found 98 on our travels, it'd have been a real liability to not be able to use 95.

we're going to france this summer where (if the tinternet is to be believed) I will be running on 4star leaded

Good luck! I've not seen leaded - or even LRP - for sale in France for many, many years. I've had issues running cars that are happy on UK-95 on French 95, though, so tend to pay the small extra (less than here) for 98 where it's available. There's also E10-95 about. Depending on the fuel pipes in your van, it might be worth avoiding that, but remember that normal 95 is E5 anyway, so it's probably not life-or-death.

[kevtherev]

Surely 2.1 and 1.9 dg heads are the same and dg heads are not so rare second hand
Second hand may not be much better than yours though
Probably best not to let them skim the water jacket sealing surface unless they skim the liner seal surface by the same ammount

They are the same..
I would be reluctant to skim, better to repair as the pitting on used heads can go past any servicable depth

JB Weld on the cleaned mating surfaces, then scraped while still wet to leave the pits filled.