Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Engine has unusual ticking noise - update

For those who remember (or care) last fall I posted a thread about an unusual ticking noise coming from my engine. I was concerned enough that I had the car brought home on a roll back. Various suggestions were made (thank you) about things to check. Before I found anything the noise stopped. During the winter and spring I installed a new wiring harness and performed a number of cosmetic upgrades. The car was not even started again until the day before leaving for GT35. After a brief test drive I left (apprehensively) for Delavan WI. The car ran flawlessly for 1800 miles. I've been driving it regularly since then. No noise! I may never know what caused it, but I will always wonder.
G T Foster

GTF.. Strange tick can be caused by a small piece of carbon breaking loose and resting on top of piston.
In 1976 I had a 94 T-bird just off warranty. Wife called me sayiong engine had blown up with fire coming out. On inspection when I arrived many people stateds they sae fire under the bonnet.I started car and it was clinking rather strongly. I drove the car home about two miles and ran a teakettle of water throught the carb with the engine running. tick was slowley getting quiet. Then I flooded the engine with a can of transmission fluid. Next morning I made a big mistake as I started the engine without covering the two tailpipes. I had two 10' streaks of carbon and gunk along my driveway.
This happened with about 50,000 mile on the car and I sold it much later with 197,000 miles travelled and I had done no repairs.
You could have had a small chunk that broke up.

Sandy, you're the first other person I have heard of using water to break carbon deposits. I have been doing that since the 80s, and people think I'm crazy....
wait, maybe that's not the reason.
Mike Parker

I learned that way back in 1949 while doing a summer job at a marina. The owner is a fantastic man with a chemistry degree and owned the marina in my home town. He sponsored me to OMC (Johnson Outboards) training at Peterborough Ontario. He is a master of improvisation and can make any engine run properly.We used that system to preclean motors prior to overhauling and what is not clean is softened especially around the valves. With transmission fluid most of the carbon is mushy.
I still do this prior to a major tune-up and it does wonders.
Water treatment is cheap and you should try it as you will like it.

You may well have solved the problem but "B" series engines are notorious for number three tappet being noisy after a fair mileage. I think that the cam lobe/tappet (ie follower) may be in an oil "shadow". My MGA engines "tick".
Barry Bahnisch

Sandy, I've never heard of this before, how do you put the water into the carbs? - air cleaners off and then use a tube? What's the rate of introducing the water into the cylinders and how does the engine manage to keep running? Ditto transmission fluid with engine running or through the spark plugs?
J H Cole

air filters off and a jug with large hose about 1/2" . Pour water into the carbs and keep engine running by hand operating the throttle. Do the same for both carbs. I find that two quarts per carb is plenty. Keep the engine (which will be rough running)going by progressivly opening the throttle. If you use the trans fluid add till the engine stops and let set overnight. Be certain to shield the exhaust when starting up as carbon and lots of gunk will come out the pipe.
Putting oil in through the plugs will not get it where it is needed the most. Around the valve stems and ports is most critical.The engine will run extremely rough but the oil will be covering everything.You can not do one carb at a time but must switch back and forth doing the complete engine at the same time with both water and oil.

While the carbon theory is intriguing, the noise appeared to be coming from inside the lower front right side of the block. It quit before I was able to probe with my stethescope.
G T Foster

GTF, that's close to the timing chain tensioner. I wonder if it something to do with a fault on the tensioner and a sloppy chain. The chain tensioner is hydraulically adjusted, and has a spring and ratchet cam device to stop the chain from becoming too slack when the engine stops and the oil pressure on the tensioner is removed. Maybe it has sorted itself out, but tt might be worth a check during the car's down-time if you are unsure of the condition of those items. It would keep you out of trouble with regard to household chores for the best part of a day if you eke it out a bit!
Lindsay Sampford

I recently had a mystery loud "ticking" noise from my engine which sounded suspiciously like a rocker working loose or excess tappet clearance on one cylinder.
After a few attempts to re adjust the clearances with no improvement I found the solution by sheer chance.

I was looking the engine over whilst it was ticking over and I noticed that the exhaust was blowing on my fingers from the rear of the exhaust manifold.
I simply tightened the rearmost brass exhaust manifold nut up and the ticking noise disappeared.
I think the exhaust gasket was being lifted by the gasses as they blew passed it and caused the click I heard.

A friend of mine who had a similar ticking problem mentioned that he had solved it in the same way.

Worth checking over if your noise re occurs

Colyn Firth

I too am intrigued at your water/oil clean-up technique. Are there any dangers in doing this? Like hydraulic effects in the cylinders causing piston damage, etc? Any need for caution in how you approach this job?
Bruce Mayo

I have not found any side effects at all. As for hydraulic locking remember that the engine is running and will continue to do so if you keep the throttle open while pouring. you must also control the amount so that the engine continues to run.
As for oiling you do the same and it finally stops when you close the throttle. then let it set overnight or as long as you wish.Just remember to shield the exhaust pipe. I use an old potatoe sack or other piece of clothe to catch all the gunk. It will make a mess.
Sometimes I have had to pull and clean the plugs to restart the engine.

I have just remembered that many years ago I had a strange ticking noise on an MG midget. That gave me the run-around for quite a while. It was at the front of the engine and was not there if I ran the engine without the fan belt. After closely checking the dynamo and water pump, it turned out to be a cracked crankshaft pulley!
Lindsay Sampford

I had a significant mechanical sounding clicking on my V*lV* - turned out to be an exhaust gasket.
Art Pearse

Sandy's marina experience makes me wonder if it would be a good idea to treat an engine that was going to sit all winter with outboard fogging oil...
David Breneman


Wow. I must admit that I would be so nervous doing that. I recently took my engine apart for a light overhaul after 20000 miles (a repaint to be honest but one thing lead to another). I found the carbon build up was very light, which I put down to modern fuels and oils.

I think I will stay in my comfort zone and stick to taking the head off for de-gunking.

Mind you, the Harrier jump jet has a water injection system though it's for increasing the thrust in the hover, rather than for purging the engine.

Steve Gyles

This thread was discussed between 31/08/2010 and 02/09/2010

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.