Does head need skimming?

Post by **PhilXXJ** » 24 Oct 2007, 21:03

im taking the head off my 1.6 diesel this weekend to renew gasket. This is due to overheating/ losing water and now smoky on start up till running on all 4. Can i visibly tell if the head needs skimming or is it advisable to get it done anyway?

Post by **andysimpson** » 24 Oct 2007, 21:10

Head is most likely dead anyway, get it checked by soemone that knows what to look for or you might be just putting off the bad news.

Post by **PhilXXJ** » 25 Oct 2007, 06:07

By 'dead' you mean warped or cracked and therefore unserviceable?

Post by **Syncro G** » 25 Oct 2007, 13:28

Is it a turbo? They are quite prone to cracking so I've been told. A N/A engine won't have as much heat to deal with so probably less likely to crack (maybe they have a history of just warping in a repairable way?) but they still get thrashed and there must still be that flaw somewhere? - have a chat with an engine reconditioner familiar with this engine to see what they think of the symptoms before you spend a penny on it!

My story is as follows... When I got mine (JX turbo) it had a suspected cracked head or blown gasket. It spat out its coolant unless you drove it VERY gently (in all other respects it still started and ran very well though). I was advised by more than 1 person (some who rebuilt these things) it was probably a hairline crack in the head that only opened up when the engine was very hot, as it would be when you put your foot down a bit (in my case exceeding 40mph it tended to be enough to achive this, whilst trying hard not to spool the turbo up). I was advised I could spend money on skimming the head and pressure testing it but if it failed (which it will if its cracked) I'd have waisted well over £50 on the scrap head in the process. Furthermore, unless it was pressure tested at full operating temperature (more expensive as its not very common apparently) there was a chance a hairline cracked head could still pass the test if the crack was small enough to only leak when hot, giving my simptons this seemed the most plausible situation for my head.

With that in mind I decided to bite the bullet and put my money towards a brand new head instead of spending some trying repair the old one and risk a likely hopeless cause. When I stripped the engine I checked the head very carefully but it didn't seem visibly damaged and the gasket was fine. New head fitted, doesn't loose its coolant so there must have been a crack in it somewhere! The old head had managed over 100k miles so if I back off when it gets hot and keep it serviced well with luck my new head should last as long again (maybe even longer as its no longer just another of the water board feat rally vans it was most likely treated as in its early life? no that probably is to optimistic!) - thats got to be a positive justification to the extra expense (which could be a saving if if its beond repair anyway), at least that's what I keep telling myself as I cane my back account.

Post by **camper** » 25 Oct 2007, 15:04

Reading through this is interesting.My van has a 1.6td JR engine fitted which is a M2 golf engine that has hydrolic buckets as apposed to shim adjustment.When i got the van the history was the engine had done 120,000 but a service history of oil & filter changes every 5000 miles and cambelt changes at 20,000 mile intervals.This could be verified by hand written pages of dates and notes taken for advisery replacement parts as a service history by the owner of the M2 golf 1.6td of which the engine had been removed.It was a bit over the top with the cambelt changes but the oil&filter changes was good news for the bottom half of the engine.Within a short time of running the van i noticed oil in the expansion tank i made other checks but concluded it was a cylinder head problem ie gasket .I removed the head & replaced the gasket but after aprox 400 miles the engine started overheating.I removed the head but this time i took it to a local reconditioner who dye tested it for water leakage prior to a head skim no leakage .The reconditioner discovered a fine crack between a inlet&exhaust valve but said it was not unusual and would not effect the servicability.So i had the head skimmed and it was reffited with new streech bolts and gasket its done about 15,000 and have no problems.I guess i took a chance considering the mileage of the engine but it runs sweet.

Post by **PhilXXJ** » 25 Oct 2007, 20:58

Thanks for the feedback

ill take the head off and have it checked out before making financial decisions

Is it ok to leave the pump and injectors connected? I guess itll have to be stripped if i have it skimmed.

Post by **Syncro G** » 25 Oct 2007, 21:15

PhilXXJ wrote:Thanks for the feedback ill take the head off and have it checked out before making financial decisions Is it ok to leave the pump and injectors connected? I guess itll have to be stripped if i have it skimmed.

You'll have to disconnect the injectors to take the head off! I left the pump where it was, only disturbing the cambelt (as you need to). I removed all the pipes and injectors (neater is hard and they can't get damaged then), raped the injectors in tin foil individually and also, using an elastic band, held some tin foil over the 4 outlets on the pump. That should stop dirt getting in. It'll self prime the injector pipes when you go to restart it, though loosening some of the pipes on the injectors and cranking a bit first can help.

Post by **camper** » 26 Oct 2007, 07:38

When i took the head to the reconditioners near me (Sutton rebore) Sutton Surrey.They said that the steel inserts that the fuel comes out from the injectors into the head would need to be pressed out.This was so that after the head was skimmed remain proud reinserted .Reason for it was when the head is torqued up with the gasket it made a good seal .There was an extra charge for this.The gasket that was fitted that leaked was a two notch after the head skim sutton rebore adviced a three notch for safety.Total invoice from them was £80.00 for the work.Replacement new streech bolts obtained was extra.

Post by **PhilXXJ** » 28 Oct 2007, 18:23

I see the pump is bolted to the block!

Tried to get the head off today, not as straightforward as i hoped. Do i need a special puller to remove the camshaft wheel or is there some other way? hammer and chisel perhaps

Post by **camper** » 28 Oct 2007, 18:40

NO NO not hammer&chisel .Lock up the cam sprocket dont use the slot at the end of the camshaft to do this.A broken camshaft will be the result.The cam sprocket is on a taper fit with no woodruff key just undo the bolt .You need to give it a strike use a hardwood block on it or a hard plastic hammer.This will suddenly loosen the sprocket.

Post by **PhilXXJ** » 31 Oct 2007, 07:16

Ok got the head off! cant see any obvious signs of blown gasket not sure if there will be any.
one thing bothering me is when i refit the cam sprocket, how do i set timing if theres no keyyway?

Post by **camper** » 31 Oct 2007, 16:23

Remove plug in the bell housing .Looking through the hole there is a V mark&pointer this should be lined up .Pistons 1&4 will then be at T.D.C.Insert a locking pin into the fuel injector sprocket this engages into the back plate.Cam should be set with lobes 1&4 cylinder head at 10 oclock and 2 oclock insert cam setting plate in rear slot of the cam.Cam wheel 18mm bolt tighten slightly as to allow the sprocket to move when the cambelt is fitted and correctly tensioned then tighten the bolt.There are no timing marks this just a basic explanation.To set it properly you really need the right tools .Cam sprocket locking tool for undoing and to tighten the 18mm bolt and a cam setting tool for which inserts in the slot at the rear of the cam.Injection pump sprocket locking pin.Some timing kits have a screw pin that is screwed into the crankshaft bottom this keeps it on T.D.C when putting a cambelt on.

Post by **PhilXXJ** » 08 Nov 2007, 21:55

I was all set to take head to have it skimmed and vacuum tested and order gaskets . Had a close look in the morning and its pretty much dead! Apart from cracks on each pot between valves, 2 or 3 waterways have eroded to less than a mil of the comb. chamber.

How do i post pics onto here?

Post by **Westy.Club.Joker** » 09 Nov 2007, 22:31

Guy selling a decent head in the for sale section, also on Brickyard

Post by **PhilXXJ** » 14 Nov 2007, 18:51

Thanks i was gonna do the head till i got round to doing an AAZ conversion but due to cost ive gone straight to the latter. Engine and box are out currently preparing golf 1.9td to go in