Lotus Elan and Lotus Elan Plus 2 Forums

Hi All,

The 3 way brass vacuum fitting at the front of my head has broken off at the end of my engine rebuild, by the looks of it it was cracked anyway, The brass thread it stuck fast in the head and i am struggling to remove it to fit another. I have tried lots of lube and penetrating substances and an "easy-out" stud remover but its not budging. Any Ideas?

Cheers Neal

Have you tried the localized freezing spray with the easy out? Used it for a stubborn broken exhaust stud. Not sure with brass, but might be worth a try?

https://www.amazon.ca/CRC-05002-Freeze- ... B000TFTH00

HTH

Stu

Like Stu i would try warming the head and then spray the broken brass section with freeze spray and try with an Ezyout. If after 2 or three goes it was still stuck I would drill it out carefully in stages until you reached the bottom of the threads and it could be collapse and removed.

cheers
Rohan

At that point, I'd be ready to drill out the brass piece. Start with a slightly bigger drill than the original hole in the brass piece, then increase the diameter by about 1/32" or .75 mm, until you get close to the thread size. Then take a small pointed punch to tap out the thin walled brass piece. Proceed slowly

Roger

If you have a good machine shop near you I'd recommend taking it to them to remove the remains of the fitting.
Had the issue of a broken and corroded water fitting in a front cover. The machine shop was able to remove it perfectly with absolutely no damage to the threads. Not sure what process they used but the cost was minimal and preferable to risking damage by doing it myself.

The polar spray hasn't worked, so it looks like careful drilling is in order. I will keep you updated..........

Hi,
In the past I have managed to remove a difficult oil gallery plug by :- using a drill of just the right size drill through completely, using a needle file create a rough Hex shape then find an appropriate oversize Allen ( Hex ) key and drive gently into the hole. Hope you get the idea.
In my experience drilling out to find the original thread without damage is a fairly precise exercise, so best used as a last resort.
Ron.

I know you have a much smaller space in which to work so it might not be possible but I had the threaded part of a spark plug broken off and stuck in the hole. My expert used a fine bladed saw to make cuts at 180 degrees from each other and it came out easily after that. If you can find a very thin saw blade it might be worth a try??

Thanks for the ideas, ill take the carbs and the radiator off to give me some room and re-assess. I have a fall back position of a 7lb hammer, it won't do any good but might make me feel better!
Neal

That thread will be a tapered BSP or NPT pipe thread. Not easy to repair if it gets damaged. It will be naturally tight because it's designed to seal. Maybe you could insert a close fitting brass rod inside the remains, solder it in and then turn the rod with a pair of mole grips?

If it were me though and given the value of the head I'd just take the head off, take it to a machine shop and have it done professionally. Been there done that with broken threads in soft alloy - is it worth the risk??

SUCCESS!

Thank god for the 7lb hammer, the mere threat of it made the offending stud give up...........

So thanks to Elanfan and Craven, your threads got me thinking, I cut and filed a metal jigsaw saw blade to fit the hole and very carefully cut 4 slots taking care to just miss the threads of the inlet manifold. I then used a square section file to insert "screwdriver like' into the slots and carefully unscrewed using a spanner on the square section. It was tight and had some sort of glue on the thread ( did not look like threadlike or silicone) but gave in the end. Good news is none of the threads on the head were touched!

On a side note to broken surfaces had a matt dark appearance to about 1/3 of the area so i presume that the thread was already cracked causing it to break on me.

I was slowly leaning to removing the head and getting it done at a shop but i have just refitted it after a head refurb (a whole different story for later), but not now necessary.

In conclusion i would like to say thanks for all the ideas and this is why this forum is valuable.
Cheers Neal

A bit late now, but I was about to suggest that if the head is on the engine, you should possibly put a thick layer of grease inside the inlet manifold and grease on any file or sawblade to catch any brass filings & "saw dust" you wouldn't want those dropping into the cylinder.

This would involve removing the front carburettor of course, but you had probably already done that.

Thought of that made a stopper to fit along with stuffed rags.

Brilliant news Neal, I love it when a plan comes together!

Good news.
What is it they say, ?Necessity is the mother of invention.?
Ron.