removing stubborn plugs UPDATE
removing stubborn plugs UPDATE
Thanks to all for the sage advice; a new plug socket, the penetrine, a cold engine and plenty of leverage meant the recalcitrent plugs obediently came out 1-2-3. Took it on a club run yesterday but I and another Series 1 were held up by an Alvis that wouldn't yield! Revving beautifully however...
Re: removing stubborn plugs
Someone gave you good advice--an impact wrench is an extraordinarily bad idea. Stick with the penetrant and be patient. (Seriously?, ten years??) Take your time, and good luck.
Re: removing stubborn plugs
Thanks...it's a credit to the engineering that it runs as well as it does!
Re: removing stubborn plugs
They can be stubborn at times. I had a plug break off once. I wonder if the penetrating oil will help as the thread and plug are designed to be gas tight.
Indeed, no helicoils. Although I have succesfully repaired several plug holes with helicoils with the head still in the car, helicoils are not considered to be guaranteed gas tight by people preparing racing engines. There are special inserts which are screwed in with a special tool and then heat expanded to really shrink into the aluminium. The head has to come off to do this.
Indeed, no helicoils. Although I have succesfully repaired several plug holes with helicoils with the head still in the car, helicoils are not considered to be guaranteed gas tight by people preparing racing engines. There are special inserts which are screwed in with a special tool and then heat expanded to really shrink into the aluminium. The head has to come off to do this.
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lucasgeheniau
- Posts: 653
- Joined: 17 Dec 2008, 20:12
Re: removing stubborn plugs
The coefficient of expansion is for aluminium twice the value of steel.
So including Huibs gas tight seal, I agree penetrating oil will be of no use, I think they will loosen best at high engine temperature.
I would prefer the air tool for loosening them.............(I dont have to remove the head when things go wrong >:D< )
Success!
So including Huibs gas tight seal, I agree penetrating oil will be of no use, I think they will loosen best at high engine temperature.
I would prefer the air tool for loosening them.............(I dont have to remove the head when things go wrong >:D< )
Success!
Re: removing stubborn plugs
Doing it from the top without taking the head off may be as suggested a bit risky, and I am not sure if the penetrating oil will be able to get past the crush washers, it stands more chance capilliarying down the open thread from the combustion chamber.
If you take the head off, turn it upside down and put penetrating oil in the combustion chamber I think you will find they will loosen off. You will have to leave it for a few days at least. Also when you periodically try to undo the plugs, keep the head warm and spray freeze spray on the threaded joint in the combustion chamber.
I have had to leave heads/blocks for upto a couple of weeks to remove plugs (or other bolts) without the risk of damage - but it never fails. Patience, as Ed says will be the key.
Your problem is probably due to the fact that the corrosion product of aluminimum has a much greater volume (when compared to the volume of its parent metal) than that of a ferrous metal. As it corrodes over time the extra space it takes up on the threaded portion creates huge pressure in the threaded joint, locking it up (ever tried to remove a thermostat on a Fulvia ?), the longer it is left the worse it gets. When you eventually get them out you will probably find lots of "white powder" - this is the corrosion product. You will need to inspect the threads in the head carefully before you put new plugs back to ensure they are are still sufficiently intact to take a plug, if they are not they will need repairing.
Good luck
Neil
If you take the head off, turn it upside down and put penetrating oil in the combustion chamber I think you will find they will loosen off. You will have to leave it for a few days at least. Also when you periodically try to undo the plugs, keep the head warm and spray freeze spray on the threaded joint in the combustion chamber.
I have had to leave heads/blocks for upto a couple of weeks to remove plugs (or other bolts) without the risk of damage - but it never fails. Patience, as Ed says will be the key.
Your problem is probably due to the fact that the corrosion product of aluminimum has a much greater volume (when compared to the volume of its parent metal) than that of a ferrous metal. As it corrodes over time the extra space it takes up on the threaded portion creates huge pressure in the threaded joint, locking it up (ever tried to remove a thermostat on a Fulvia ?), the longer it is left the worse it gets. When you eventually get them out you will probably find lots of "white powder" - this is the corrosion product. You will need to inspect the threads in the head carefully before you put new plugs back to ensure they are are still sufficiently intact to take a plug, if they are not they will need repairing.
Good luck
Neil
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lancialulu
- Posts: 244
- Joined: 21 Dec 2008, 19:53
Re: removing stubborn plugs
Best to leave the head on as the engine is the best anchor when trying to apply socket wrench.
You could try Wurth's "RostoffIce" - hard to spell and get hold of - but it penetrates and micro freezes at the same time allowing some penetration of lubricant - not sure this would still get past the gas seal of the plug.
Anyway - you are lucky as 1300 heads are still very common unlike the 1600!
Tim
You could try Wurth's "RostoffIce" - hard to spell and get hold of - but it penetrates and micro freezes at the same time allowing some penetration of lubricant - not sure this would still get past the gas seal of the plug.
Anyway - you are lucky as 1300 heads are still very common unlike the 1600!
Tim
Re: removing stubborn plugs
I used this contraption called a vice 