A B20 Story

[DavidLaver]

I think it has the makings of a chassis rotisserie. 

Speaking of which something to spit roast on?  The strength of it a fatted calf as much as a suckling pig.

[the.cern]

Will you be able to use it as a test stand as well ? Maybe with one or two mods ....

Perhaps you could rig up some kind of chain drive to the wheels and get it to drive itself up the slope ?

Inspiring stuff, I will have to build something similar for the Aprilia engine rebuild.

A couple of interesting thoughts there Simon, I will seriously consider the former, but please forgive me if I pass on the latter!!!!

I will see how I get on with the re-build. Hopefully today I will start dismantling it, a few boxes, a camera, a notepad, marker pens, tie-on labels and a clear head, that should be enough to allow a start!!!

                             Andy

[the.cern]

I have had a great weekend away, feeling quite tired but ready to tackle the engine.

In Sandwich I came across Roses Garage. They do routine work, but apparently have a good reputation in classic car circles. In for work were 3 Lea Francis, I think they were 40s/50s, a 1950s Oldsmobile and an HRG. Also there was the owner's toy, a 1983 Williams F1 car and his two go-karts, capable of 150mph!!! I am sure someone in the Club must be aware of this establishment.

I chatted to their engine specialist and, quite  predictably, got onto the subject of my B20 engine, particularly the cracked block and the missing core plug. His response was to get the crack welded and, since I was having that done, I might as well have the core plug hole welded too. His alternative thought for the core plug problem would be to drill and tap the hole and screw in a new plug. Neither of these suggestions had crossed my mind. Add them to David's thoughts and suddenly I have options, a bit of a luxury!!

Now I must grasp the nettle and get started!!

                                     Andy

[DavidLaver]

http://www.dover-express.co.uk/Unassuming-garage-owner-Grand-Prix-champion/story-15361757-detail/story.html

http://weekenderonline.net/richard-barber-garage-owner-and-racing-driver/

http://www.geograph.org.uk/photo/2909611

https://www.flickr.com/photos/rikyu/6084731456/

https://c2.staticflickr.com/4/3270/2931349415_fc8251e8a0_b.jpg

[the.cern]

Yesterday and today it was back to the workshop, only 4 hour sessions as family matters intrude.

The rocker blocks have been removed, not difficult, particularly as only 4 of the 12 nuts were restrained by the tab washers although all 6 washers were in place. The rearmost  oilway on each side was half choked with semi solid oil, I have no idea what may have caused that.

The next step must be to remove the heads. I did not have the sequence for undoing the head nuts so merely discharged most of a can of WD 40 onto the head nuts and into the cylinders. I then started to measure up for a  head puller. This will work on the simple principle of a plate secured to the head with the 6 studs which held the rocker blocks. The plate will be drilled and tapped at points directly above the head studs. Simply by screwing bolts through the plate onto the tops of the studs the head will be lifted. It is important to ensure that the bolts are screwed down evenly so that the head is lifted straight and true up the studs. Copious amounts of WD 40 will be applied to the studs once the nuts have been removed to provide lubrication and to try to break down the deposits caused by the electrolytic corrosion between the steel studs and the alloy head. Making the puller is slow work as it must be accurate. I am making a pattern in 10mm ply so that hopefully I will get real thing right first time.

More to follow ....

                           Andy

[Charles T]

Hi Andy,

When my B20 was rebuilt a few years ago, the heads were seized solid and required some persuasion to remove them cleanly.

I have not got the paperwork to hand to check but my recollection is that heat was applied to loosen them off.  Several cycles of heating and then being left to cool naturally were required but they came off in the end. This may not be a feasible option for you but it is worth considering.


Charles

[Niels Jonassen]

When one headgasket went last summer I believed that it was a simple matter. How wrong can you be? The solution we chose was to make a tool that could govern a grinder and then grind our way down through the studs. The studs are 8mm and the grinder was 7mm. We stopped grinding about 10 mm short of the surface of the engine block in orden to have something to grip when removing the studs from the engine. Even with that Little stud left the heads were difficult to remove, We had to use a steel rod of approx. 1 m to leaver the heads off. May I add that we did not damage anything? I shall be interested to see if you can apply enough pressure using your system.

[frankxhv773t]

When Martin Buckley wrote about his first Flaminia Berlina in "Staff car Sagas" his father had to remove the heads using a technique of cycles of heating the head followed by cooling the studs with drips of cold oil. I believe it took a long time but the heads finally came free with a satisfying clunk.

[the.cern]

I have always been wary of heat and alloy castings and hope I will not need to venture down that route.

I did a lot of research into problems associated with removal of aluminium heads arising from reaction with the steel studs before deciding on this my favoured  method. Two methods that received the worst press were:-

1) lever the head off
2)  hitting the head with a soft headed hammer

The two methods that seemed to have the most support and also the best engineering rationale were obviously that which I will be using and also the use of a thin walled tubular drill bit which will fit over the stud but not cut into the head. This would cut through the corrosion products that effectively weld the studs to the head. Hours of searching on the web to source such drill bits resulted in abject failure. That is how I arrived at the chosen method!!!! Having removed the head fixing nuts I consider the tubular drill bit method sounds better in theory than it may turn out to be in practice. This  because, on my engine at least, not all the studs are central in the hole, indeed some appear to touch the head casting so, no matter how thin the drill bit wall is, it will cut into the casting!   

I have bought the steel plate for the puller, 12mm thick, although I am sure 10mm thick would be adequate and a drill bit for the 8dia bolts that will bear onto the ends of the head studs. Today I learnt that the tapping diameter for an standard 8mm bolt is 6.8mm. For 8mm fine it is 7mm, but I am sure you already knew this!!! Cutting 12mm plate with an angle grinder is fairly tedious, but it does beat a hacksaw. Having completed the plywood template I marked out the array of holes to be drilled, 6 at 8.5mm dia to secure the plate onto the head using the rocker block studs and 16 at 6.8mm dia to be tapped for 8mm dia bolts to bear onto the head studs. The plate fits snugly over the rocker block studs, I have yet to finish drilling the other 16, only then will I find out how accurate my setting out has been!!!! I will let you know .... and I will be honest, even if it turns out to be crap!!!! Hopefully more to report tomorrow.

                                              Andy

[the.cern]

I said I would be honest ... as I said the 6 holes for the studs for the rocker blocks were spot on!! The 16 holes to align with the head studs were drilled and checked before being tapped. 15 were good, but one was appalling, a gross error, some 7mm out!!!! The advantage of a gross error is that there is no conflict between the correct location and the cock-up location. So that one hole was re-drilled and then the simple task of tapping the 16 holes for M8 studs. Simple yes, tedious yes, hard work, yes!!! However, it was done.  Then the 16 'pushing bolts' were screwed into the plate

Now to see if it will work!!! I screwed a nut onto each head stud, flush with the end of the stud to increase the bearing area for the 'pushing bolts' in the head puller. I said 15 were good, but they were not all perfect!!! Then it is just a matter of going round all the pushing bolts, bit at a time, to apply lift to the head, pulling it up the head studs. The first 3 photographs show the puller attached to the head ready for action, the 4th shows the head some 8mm free from the block!! It worked, eureka!!!! With the head pulled further up the studs I could get a sight of the top of the block, not good, see photograph 5. Photographs 6 and 7 show the top of the block and the head as they came apart, definitely not good!!! The last photograph show the block and cylinders etc after I had vaccuumed out the deposits!!! Definitely not good. Bear in mind this is the supposedly good side of the engine, it is the other bank of cylinders that has the failed core plug in the head!!!!

So, good news and bad news, I have a tool that should get the other head off without damage. Bad news is that I will probably need all the usual parts plus liners, pistons, shells, valves with guides etc etc. Oh well, I am enjoying myself!!!

I have attached the first 4 photographs with this post, the other 4 will be on a separate post .. file size issues!!

Tomorrow (if I am allowed) will see the other head removed and whatever that reveals !!!

[the.cern]

The other photographs ....

[simonandjuliet]

Ingenious - I had faith .....

Looking forward to the next pictures.

ps "Our" (now Kennedy) B20 had a heli-coiled block and bolts to get around this whole head removal problem. It even meant that I could change a head at the side of the A1 after dropping a valve - but that is a different story.

Maybe worth thinking about ??

[the.cern]

Take a look at the back right-hand stud in the last photograph, it is reduced to about half its diameter, ie about a quarter of the csa!!!!

[DavidLaver]

What a brilliant method...

At least parts are available, and from a number of suppliers even in the UK.  Off the top of my head Kevin Macbride and Tanc Barratt as well as the obvious Omicron and Peter Harding.  Anyone else got supplier suggestions or experience buying direct from Italy or where ever the parts are made?  Is there a variation in quality or do all the parts have a single source?

As for "reasons to be cheerful" with the corrosion damage "getting some welding done" and "getting a lot of welding done" are surprisingly similar.  Getting it there, cleaned and inspected, agree to the work, it being the focus of a half day with much of that being preheat and whatever other preparation however much or little actual welding is needed.  Scrambled eggs on toast for one or four its much the same job.

For a one stop shop there's Jim Stokes.  When I looked they were good value on a per hour basis and were able to turn work round quickly.

http://www.jswl.co.uk/

The other "big name" that comes to mind is Serdi

http://serdi.co.uk/

Despite the name this company might be worth a call:

http://www.castironweldingrepairs.co.uk/

This one popped out of Google, only in Biggleswade:

http://www.stotfoldengineers.co.uk/stotfold_engineering_blog/2010/03/18/aluminium-welding-and-repair/

I'll have a look in the VSCC letter for who advertises.

Tim Burrett would be an obvious person to talk to.  How long until the Aurelia lunch this year to go and "ask about" for advice and experience?

Finding the right specialist is important and not easy.  Christo was good enough to share his regrets:

http://www.lancia.myzen.co.uk/forum/index.php?topic=7594.15

The other cliché is the specialist who'll say "drop it off and I'll have a look at it when I get a chance" and it will still be there a year or so later.  It would be such a shame to loose momentum for other people's reasons than your own.

David

[DavidLaver]

I forgot "our Aurelia" had bolts not heads.  It worked really well.  My story is having a head on and off and on and off trying to chase down what turned out to be a water leak through a crack/pin hole in an inlet port.  I fixed it with a bit of wire and araldite which held until Tim Burrett got it welded.

The job itself I can remember like it was yesterday.  What I struggle to visualise is the garage at the side of the house clear enough to run a full size car in and work on it.

David