Calling jimfoo

[mud and diesel]

Hi mate, I’m a new member, but I am always checking out the site! just a small favour I would like to ask  
I have recently put a 1.9 AAZ in my Suzuki vitara using the acme conversion kit, I was previously running a 1.6td but had a great deal on a low mileage AAZ. (Free!!) anyway the thing is, would you happen to have any images of the block with the water pump removed, I ask this because, the previous owner thought it was a good idea to use black silicone sealant as gasket material, rocker cover, sump, oil filter housing etc!!  Luckily he was doing a diesel conversion on his and had not run it like this, I fixed all this, but I didn’t think about the water pump! I have put about 1000 miles on it and I am very happy but I have recently noticed a small (or big) issue. I have a constant stream of bubbles going to the header tank through the small return pipe?? The engine runs perfect other than this! cold starts great pulls really well, no oil in coolant, no coolant in oil, no steam out of exhaust, could it be a cracked head, or head gasket? Thank you for your help on this.

[bert]

hi mate,i have 2 vw diesels and a petrol ve and all have air bubbles going back to the tank,dont worry about it,all other vws i look at do it,
Bert

[mud and diesel]

Bert! i hope your right! im hopeing its me being a paranoid mess! Thing is, i have done about 4 of these conversions and none of the others have done it! although the other engines where 1.6 TD's. The thing i cant get my head around is where are the bubbles are coming from?? any idea?
I asked for jimfoo becouse he has put an AAZ diesel in his truck so mabye he would understand my issue, but all comments are very welcome.

[jimfoo]

The best image with the water pump removed is this one.

Does pressure build up in your cooling system if run for a short time when cold? If so, it may be the head gasket. There shouldn't be bubbles as far as I know, but my setup is different, and I wouldn't be able to see bubbles if I got them

[mud and diesel]

Thats a perfect picture thankyou! you said about pressure building from cold? I does, but not a large amount, if i open the cap before i start it to relieve any residual pressure then start it, after about 2 mins of tickover it will sound like a bottle of pop when i open it, just a small pphhttt.
Ps your rover biuld is inspirational! there are loads of landrovers over here in the uk but they all have range rover v8s or 200tdis, the only engine conversions are ford and other van diesels. thanks again.
Pete