Compression test low, unable to bleed and overheat.

[Simon Jones]

Sounds like a very pragmatic approach . I've changed a head gasket but was fortunate that the head was undamaged. The gasket failed on a 5 minute trip up the road so had barely got up to normal temperature so there was never any overheating incident, just coolant being pressurised and forced out the header tank overflow.

I had the head skimmed, tested and popped it back on. I put another 15,000 miles on it before i sold it and the new owner has done a fair few miles since it was sold with absolutely no problems.

Whatever you do, I would strongly advise you to read all the info on the forum, especially regarding 'decking the block' and the use of WellSeal compound to ensure a really good seal. This was my block all cleaned up before re-assembly:





This was the head as good as new after skimming:





I'm afraid I can't offer any advise on where to source a good quality head although the ones sold in the club shop will no doubt be the one to go for if you were not on a tight budget. As with many things, you get what you pay for, so avoid anything that sounds too good to be true.

[Weeduggy]

Well,

Head is going in on wednesday to be tested and skimmed if ok.

Most of the parts on order for delivery this week.

With regards to decking the block, I've read people have used a flat piece of marble with 120 grit, i assume wet and dry. Where do you get a Flat piece of marble thats not a Fireplace, Cos thats all i can find at the minute!!

[helen&tony]

Hi
A flat piece of marble....mmmm....thinks... .... ....graveyard????....
OR.....
http://www.ebay.co.uk/itm/Smooth-Black- ... 19e437e37a

Cheers
Helen

[Simon Jones]

I went to local granite worktop company & they let me have a rummage in the scrap pile in return for a £5 donation towards their tea / beer fund. It's very easy to trim to size using an angle grinder and cheap diamond cutting disc. I think I trimmed it to about 20cm square, but measure width of block and add a few cms. 120 grit is far too course and I think is was closer to 1200 or even higher. I got it from a proper engineering supply company on a local industrial estate.

[the laird]

If you're stuck a bit of decent wood will also do the trick ie hard block.plenty joiner shops have scrap bits

[Simon Jones]

The reason for using marble or granite is that it is a perfectly flat surface which cannot distort when you are apply pressure from above. It also has a bit of weight which makes the job slightly easier. In an ideal world, you'd take the engine out & skim the top of the block, so the DIY process has to be done with care to achieve a good result.

[Weeduggy]

Well the results are in and as expected the head is cracked between 2 and 3. Getting a complete new head all built up from the place i had it tested. Going to stay local as it might ease any issues should i have a problem. Going to cost me about 500 quid unfortunately. Got too much invested in the van to let it die or sell it on. Just might be skint for a while!!

[the laird]

Best o luck weed out ,think you're doing the right thing,it'll be enjoyment from there on in

[Weeduggy]

Rebuild Time,

Been away again for 5 weeks so now its time to rebuild, Replaced water pump, oil and fuel filter. Started cleaning the block of the old gasket but there's 2 tubes sticking out the block. How do they come out, Didn't want to just try and prize them off in case of damaging something, Noticed in the pics they are not fitted though!!

Cheers

[Weeduggy]

And with regards to using the well seal,

Is it a small bead around both sides of the gasket or just the top face that mates with the cylinder head.

[haydn callow]

You will almost certainly need a new head......your old one may pass all the tests but still be goosed.....look for very feint lines around the exhaust valves........like Simon has said.....it will be the head rather than the gasket.

[Simon Jones]

The small pipe with the o-ring is the oil feed to the head. You will destroy it in the process of removal, but readily available from Bellhill Garage. Best method is a can of freezer spray form Maplins or RS to shrink the part: give the pipe a real good dousing and then with the sharpest grippiest set of Mold grips you can find, gently twist it out. The other one as I recall is more of a locating dowel and should come out quite easily but you may need to use the same technique.

Wellseal (again as I recall) is smeared over the whole surface of both sides of the gasket, but the tube should have instructions.

[Weeduggy]

Well it's all back together and coolant system bled with no problems. Temp gauge sitting at 11 o'clock position. Took it for a short drive, got it up to 60 mph and up a steep hill. All is well. Hopefully that should be the end of it for now!

Another Bongo saved.

Roll on the summer and barbies on the beach and camping with the kids!!

Thanks for the helpful advice.

[scanner]

Temp gauge sitting at 11 o'clock position.

................ and if it hasn't been modified to read accurately that's all it will ever sit at.

[Weeduggy]

Temp gauge sitting at 11 o'clock position.

................ and if it hasn't been modified to read accurately that's all it will ever sit at.

And how do you modify it?