Cleaning Engine Block / Cylinder head Questions

[sheepy]

Well, I've finally stripped the head off my XJS, and have now started the process of cleaning everything up. Surprisingly there was no real sign of HGF, but the water channels through the gasket around number one piston were completely blocked.

First step is to clean the crud from the gasket off the block and the head. Does anyone know the best way to do this? I tried WD-40 and steel wool, but the process is very slow. Should I use a steel blade to scrape the surfaces (eg a clean wood chisel)?

The pistons were covered in carbon, and I was able to clean this off easily using "Wynn's Carb cleaner" which softened the deposits nicely. Now I've got to strip the valves out and clean / reseat them. Anyone removed valves off a Jag head before?

Any advice or tips welcome,

Sheepy

[Boosted LS1]

When I remove gasket crud I hand hold a stanley blade then I move onto fine emery if needed.

[deltaf]

Boosted LS1 said:

When I remove gasket crud I hand hold a stanley blade then I move onto fine emery if needed.

I use the same method as Boosted. I also use TFR, (traffic film remover) that is NON caustic, to remove deposits of gum and carbon.
If you cant get the very heavy stuff off, try oven cleaner, but do a test somewhere in case it attacks aluminium.
The TFR has the advantage of being water soluble so it can be rinsed off with water, and the residue poured down the drain...(its biodegradeable too).

[GreenV8S]

For sealing faces you should avoid using any hard tools. You can make a very effective soft scraper by flattening the end of a piece of copper pipe. With care it'll scrape the crud off without any danger of damaging the underlying metal.

[Boosted LS1]

Or, you can dip it in something like Neostrip. Deadly but good at stripping especially aluminium. Brings it up like new. You don't want this stuff in your garage though and it's very expensive.

[z_chromozone]

Sheepy,

to get the crap off the block I have always used wire wool and some medium grit paper to get the scratches out. Be careful not to let any stray pieces of wool, or grit get in the bores though. I would not bother doing the head, just get it skimmed (ca. £25). A place in Bletchly did mine and cleaned the thing up really nicely. While it was being done I had chance to relap the valves and clean the deposits off. With new valve stem oil seals the thing looked like it had just come from the factory.

Z

Just had another thought, is your engine OHC. If so you may need a modern design valve compressor to get the reach down into the valves. I got one for £50 to do my head and it worked a treat compared to grandads 1940's thing, which I bent trying to get the leaverage. You are welcome to borrow if you like, it will probably not get used too many times in my life.

Remember to keep an eye on those pesky collets

Z

>> Edited by z_chromozone on Tuesday 9th December 16:06

[stevieturbo]

You can actually buy gasket remover, though it can be expensive, but does work very well at softening the gaskets for removal..
Ive used it a couple of times, but mostly use a sinple scraper with stanley blade in it. Once its blunted a bit, its unlikely to do any damage to teh surface, but still wokrs well to remove crap.

[numbnuts]

PETROL OR PARIFFIN FOR CLEANING OFF THE OIL
I ALWAYS USE A SCRAPER TO GET OFF ANY GASKET OR STANLEY BLADE FOLLOWED BY 80 GRIT SANDPAPER WITH A SANDING BLOCK

[danhay]

The Stanley blade is a good idea. I've used a razorblade in the past, and it's got the sharpness to remove crap and you can feel if it's digging into the head/block before you do any damage.
Chemical removers may well help too?

[Sheepy]

Guys,

Thanks for all the replies

Hopefully I'll get a bit more done this weekend (depending on the weather). Mrs S won't let me bring engine parts into the flat

z_chromozone : Who in Bletchley did your head? Mine's a DOHC ally head. The valves are deep seated, but I'm hopefull my valve-spring compressor will work.

I'll dig out the old stanley-knife and see how it goes. As for getting bits in the bores, I'm going to clean each one out once I'm done.

Sheepy

[z_chromozone]

The guys are

K&J Engine Services Ltd,
Unit 11a Home Farm Ind Estate
Sherwood Drive
Bletchley
01908 641750
01908 646913

I always use them and so does my local garage. They also sell headbolts / oil seals and gaskets, these are often less than the motorfactors can supply them for.

The place is right at the end of Sherwood Dr, at the opposite end to Bletchley Station.

Good ol' boys,

Z.

[WilliamBall]

I don't guarantee its the right thing to do, but every time I've rebuilt bike engines I've always used a pressure washer to clean the head/barrels/crankcases. The come up great, and I then soak them in oil afterwards to make sure all the water is gone before wiping them off. Dunno if its the right thing to do, but it works for me.

Also got a mate who builds classic [60s] japanese engines for racing, and he uses a dishwasher! Doesn't tell the missus, but the alloy parts come up a treat.

WB

[z_chromozone]

Sheepy,

remember to lap your valve seats before you get the head skimmed, that way all of the grinding paste is washed off with the swarf. Numbering the valves with a big black pen helps you remember which seat they fit into when you knock the whole lot over.(Speaking from my own brainless experience).


Z

[Sheepy]

Thanks Z,

Hopefully I'll get started on the valve removal on Saturday. The valves are coated in carbon (and some have what seems like a mineral deposit built up on them). Should prove to be an interesting challenge

As for the gaskets, the one I removed was oem, and it looks like the water holes were too small, so the flow to the head was too low. I've been recomended to buy the genuine Jag head-gasket, but that oem are OK for the rest of the set (valve-stem seals, cam cover etc).

I'll ring that place later to see what they quote for doing my head.

Sheepy

[z_chromozone]

If you don't have a lathe then use an old electric drill in a vice. The valves fit in the chuck ok and an old file gets off the deposits. The lateral force does knacker the drill bearings a bit, but they come up like new.

Z

[Sheepy]

Just spoke to K&J

To skim the head (with valves and cams removed):£28

To recondition head (ie I supply it as is, they do the valves, de-coke the head etc): £300

Guess I'm going to do the valves and de-coke myself. I'll check the head and only get it skimmed if it obviously needs it.

Thanks for the contact.

Sheepy

[z_chromozone]

Bloody hell £300. I guess that that would include new valve guides and seats, but even so.

I actually quite enjoy the process of taking the thing to bits and puttin it back together. To do my 16V head it took about 5h. That included taking the valves out, decoking the valves, polishing the inlets with a drill mounted wire brush, fitting new valve stem oil seales and lapping the valve seats with corse and fine paste. The final assembly was a pain because of the collets, they needed real dexterity to get back in (blob of grease on the screwdriver trick).

Really good feeling when you see the whole lot back together sparkeling like new.

Remember not to get the cambelt one tooth out

Best of luck,

Z.

[Vag man]

Hi im new around here how are you all doing im chris

im not sure about your head application but at work we just use a pice of fine grit sand paper and some wd 40 to take the old gasket off the faces of the block and the head it seems to work well to clean the water duckts out we generaly just use a small screw driver once we have finished we just blow the bore out with a air gun

[sheepy]

Hi Vag Man , welcome to PH!!!

I'm assuming that by your name you work for a certain germanic motor group

Thanks for your comment, I'm going to try scraping the worst off using an old stanley blade, and then finish off with some fine emery paper. I'll clean and blow-dry the bores, and also clean any debris from the water channels.

On the head, I'm going to strip the valves out one at a time and clean / lap them in. The exhaust valves seem to have a mineral build-up on them, and each chamber is pretty chocked with carbon.

I'll get a few pictures taken and posted for you all to see (thread is worthless withou piccys!!!!)

Sheepy

Edited because my post only made sense after a bottle of a rather tasty red!!

>> Edited by sheepy on Saturday 13th December 16:05

[grahambell]

Hi Sheepy,

For cleaning the crap from your combustion chambers you might want to consider a rotary nylon wheel. Like a rotary wire brush but with nylon rather than metal bristles.

Not used one on an ally head, but have used them on pistons and other ally components. Shift the crud a treat, while the nylon bristles don't damage the surface, just burnish it.

Try asking at you local ironmongers or DIY store.