DJ2.1 Rebuild

[mrhutch]

it's not going to be feasible to weld it in situ?  probably not. 

I'll page Ian !
 

[maxstu]

What is the size of the hole/tapped hole going into the waterway?

Just draining coolant from 3 and 4 via drain plug between pushrods

[tobydog]

Another type:

https://www.sfckoenig.com/sealing-produ ... anders-en/

[R0B]

After all the work and time you have put into it, Stu. I would be very tempted to buy another new head. More expense I know. But for peace of mind, it would be worth it.IMO.

[silverbullet]

This has been brought to my attention.

I would drain down, wash out the stud hole with clean water to remove any coolant traces, get the hole dry.

Then go and buy a small bottle of Hydraulic seal e.g. Loctite 542 or 577 (check the application) or equivalent. Thicker is better.

Liberally coat the hole and stud, wind it in, come back the next day and get it refilled.

Fixed.

[silverbullet]

PS you can buy Loctite in 5ml bottles, its damned expensive but always useful to have one in your toolbox.

[maxstu]

Thanks to both above for the info and advice.
I have just come off the phone to Weimarbus
(many thanks, Andrew) forum member and he has come up with a solution.

Either myself or my mechanic next door neighbour (hopefully him) will drill out 20mm using two stages. First 9mm. Then again at 9.5mm or 10mm. This new hole will leave a decent shoulder.
Then taper tap out to? The replacement stud is 10.82mm by 7.86mm, what final size drill and tap should l use on the 10.82mm thread?

Then use a bottoming tap to just before end, leaving stud to bite into the last bit of aluminium. A bit of JB weld at bottom of hole or around stud thread and wind in.

[maxstu]

This has been brought to my attention.

I would drain down, wash out the stud hole with clean water to remove any coolant traces, get the hole dry.

Then go and buy a small bottle of Hydraulic seal e.g. Loctite 542 or 577 (check the application) or equivalent. Thicker is better.

Liberally coat the hole and stud, wind it in, come back the next day and get it refilled.

Fixed.

Thanks.
Was typing my last bit as you were writing the above.
I could try that first.

I cant see the hole that is going into the jacket. But it is at aporox. 3mm in diameter, according to my trusty kebab stick.

Ian, many thanks. Would you please confirm last word. Refitted or refilled? If latter please explain.
Regards
Stuart

[mrhutch]

refilled

[maxstu]

Im going to take out all stainless studs and check each hole before l do anything else.

[maxstu]

refilled

Aha! Of course. With coolant.

[silverbullet]

Im going to take out all stainless studs and check each hole before l do anything else.

Be thorough, its not a lot of time expended and it could save a lot of aggro later.

Ask me how I know...

[maxstu]

Haha! I hear you.

All stainless studs removed and depths of threads in both heads measured. All, apart from the No. 3 lower manifold thread are within a decent range of 26-28mm in depth. So still enough meat behind them not to cause too much concern.

Yet No. 3 lower exhaust stud hole measures a whopping 31mm in depth. So taken to the limited and beyond. Someone with bear heavy paws looked away while drilling, perhaps?

A bit annoying as the SS stud feels as if it is bottoming out at around 23mm. So that is where l stopped turning it in. But l should have thoroughly checked this before fitting both heads to the engine block and not at this later stage. Live and learn.

Being by the coast l have a few yachting chandlers to phone or visit tomorrow. Perhaps they stock the Locktite Ian recommends.

However, I'm a bit concerned about refitting a stainless stud into aluminium after applying 542 or 577. Will it be strong enough at manifold temperatures? Or the expansion difference between stainless and ally causing a leak? You know, keep me awake, numpty stuff.

JB Weld sell a waterproof, high temp marine version. Perhaps plug the hole with this first, reducing the hole depth by 3 or 4mm. Let it cure, then add Loctite, too. But use a steel stud instead of stainless?

Decisions, decisions....

[mrhutch]

Just do what Ian said.  No need for anything else or JB weld

[Ian P.]

Would an old-fashioned thing like a core plug work, p'raps? It must be said that I'm in  no way an expert - just thinking out loud....!

Ian P.