Pics on me doing my 1st a4 head + unsticking stubborn valves ++

[CamaroMan]

(wd u nice chaps hold off comments till I'm done, just so the post is contiguous tx

Hi all - so finally got down to doing some of the real nitty gritty today -

I decided to write a thread aimed at novices / first timers - hope it helps someone! I might have missed sth but I hope not!

This motor was running great/bad/great/bad - eventually found some stuck valves.. tried MMO, tapping with a allen key / etc - NOTHING worked, not even close.. these puppies were stuck!

Comp test showed #1 and #2 on 0 compression so I thought it was a head gasket..

Here are some pics and tips I picked up regarding stuck valves (alot of it from the very knowledgeable threads/ppl on this site!)

It's quite easy getting to the head. Remove manifold with carb and exhaust flange and cooling connections. Plug wires and few small things..

Removing the head was tricky - took about 3 hours!

For those that dont know - the head nuts go on to studs (3/8 coarse in the block and 3/8 fine on top).

A heat gun will DRAMATICALLY help u get the nuts off (this will be the first challenge!).

I had a new impact cordless drill and on the lowest settings worked mine out with kroil and patience. The really tight ones need to be worked out/in/out/in to break loose grit/rust and let the oil soak deeper - LEAVE overnight if they are real bad.. Good time to do this is while u wait for parts..

Heres a pic showing the head bolts (undo them in a clockwise pattern starting from the outside - if possible!)



Once u get the nuts off (sometimes the whole stud will come out - thats fine for now)

To get the head loose it probably the hardest part - unless it was recently put on! Rust builds up between the head and studs - expands and that sucker will stick like theres no 2moro!

Penetrating oil! A trick (from Don Moyer) is to put a nut on the stud and give it a few firm taps to break the crud loose. I found the stud will usually sit against one side of the hole leaving the other side open for oil to get in. Take a note where the open side of the stud is and tap the stud (with nut on) in that direction.

When the oil soaks down thats good - Now get 2 (or 4) strong scrapers, not the flex painters type - Harbor freight sells strong ones with a angled edge.

Wedge these in between the head to get a gap.. from there move on to something stronger (blunt chisel as per Don - I used screw drivers gently prying)..

Eventually I got my head loose - but a LONG way from off.. depending on where its stuck - mine was in the middle, and I rocked it backwards and forwards for 45 mins prying.. knocking the head it back down and up over and over -

U can pop plugs in and buzz starter to assist, but not too much, few spins to see if she breaks looser..

All the time keep an eye on the studs - soon u will be able to see which ones are loose and not - focus on tapping / oiling the stuck ones.

Do Not try lift head up from one side - it has to come up level.

Once its off go grab some cold beers - I hope u didnt break any studs off and the worst is hopefully over!


Head off:




Now is the time to clean the head and block - if you havent done this, remove the big flaky bits gently.. as the dirt gets smaller be careful not to mess it anywhere. There are many ways to do this - and cast iron is forgiving, just donit gouge at it.. a hack saw blade has always worked very well cleaning up small gasket pieces - go over it 10 times, trust me u will always find more pieces u missed..

If some of your studs came out - get a 3/8-16 coarse tap and run it thru each hole - cleaning between each pass. These go thru the block into water passages so about 1/2" deep shd be fine.

Use high quality taps!! Craftsman, blue point, UK, Japanese etc are usually very good. No Chinese!! U will damage the threads,esp the fine ones!!

The stud tips are 3/8-24 FINE threads - If the rust is bad - use the "start from this side" facing the stud, then flip the die over and run it again - with some oil. You should now have nice clean studs/holes.

Now you also have to clean the studs themselves, the shafts get very rusty.. Wire brush on a drill or scraper - get as much of it off.. Wd40 and steel pot cleaner. U won't get it all off..

This is all head gasket prep done. If you arent doing valves then from there u can do a final clean and assemble (the heads are torqued in 3 stages 20/30/37 ft lbs) - in a circular pattern from the CENTER working outwards in a criss cross spiral.

Light oil is suggested but since there's a chance of steam and water making its way up the studs, I might opt for a non hardening gasket sealer or something similar under the nut heads.

*** if u pulled a whole stud out you HAVE to put thread sealer on threads,it goes down into water jacket.

After the motor has run warm - torque it again. If any of the nuts move slightly repeat this step.

An idea of what lurks in the old threads!





You can also use a machinist straight edge and a feeler gauge to check the block / head for straightness (this is quite easy.. just do a criss cross pattern from various angles - sometimes shining a light from behind the straight edge can reveal gaps).

I almost always put a very thin gasket sealer around all water ports/jackets - its very common for old cast iron to develop pits so this is just a measure ive taken over the years.


(to be continued in next post)...