So, i have a '76 308 GTB and recently changed the sparks. One of the rear sparks had a little dust come out with it (on the outside) and so on investigation i could see grit down the tube where the plugs live. I used a vacuum on each and every one before removing all the rest. However, 2 of the front sparks were really badly corroded and felt wet when i removed them. I purchase an inspection camera with a flexible lead and i can now see that some rusty water has gotten into one or two of the cylinders. There may also be a little grit. I put this down to the rubber gaskets that seal the plug holes getting old and leaving gaps where stuff can get in. So, the big question is - is there any way of cleaning the cylinders (eg flushing with oil and turning it over without them in) or should i really be thinking about lifting the engine out? Any advice would be great! I cannot imagine i'm the first with this problem, considering that the front sparks are right under the lip to the engine lid!! Cheers guys!!
The advice I have is to clean around the plugs before they are removed, of course. I would use the vac and reduce the hose size down to a small enough tubing that can be inserted into the cylinder. Compressed air may only serve to embed debris further into the ring area, so I wouldn’t suggest that. When all done, seal the new plug boots with a sparingly applied amount of di-electric grease.
Thanks Street surfer, Unfortunately the plugs all got changed. I did vacuum them all beforehand, but believe there was just too much corrosion for the vacuum to remove. It would have been loosened when the plugs were undone. I did vacuum once more after the plugs were out too. The issue is that the rusty water is now in the cylinder, so any advice on possibly flushing or rinsing out would be very welcome
Hi Tim, It was still wet? Did it rain or did you wash the car since the last run? I'm thinking that if it is exterior water it would have evaporated from a hot engine. Otherwise, does it smell like coollant? There might be a bigger issue lurking... Franny
Certainly no expert although I’m sure the guys ( and Gals) will be along shortly to give you some expert advice. My first thought would be to pull all the plugs and totally saturate each cylinder with PB blaster/WD-40 and let sit for a few days., then turn the engine over by hand with plugs out and flush as much crap out as possible. Just my 2 cts.
Just a quick comment about those big plug gaskets... They need to breath or, at least in our car, they will pop themselves off the spark plugs. This happendjust a bit before I tried to pass a super slow truck up in the mountains. Always entertaining when you drop three cylinders under load...
Thanks guys! Thankfully the water is definately in there from the spark plug well, and not coming through from the cooling system! What do you think about flushing the cylinders with petrol and then turning over with the plugs out in order to kick out any possible rust or grit??
Water in the spark plug well was a problem from day 1 of 308 production. I don't know about the GTB/GTS but the later GT4 (mine is a '77) has some shielding on the inside of the engine cover to divert the water away from the plugs.
I think OP is asking about water and dirt that got into a couple of cylinders when the plugs were removed. Not an expert, but if this happened to me I would remove the plugs, attach a tube to my vacuum cleaner and clean out the cylinder via the plug hole, confirm it's clean with an inspection camera, then be done.
As Ron said in the first response, tape a suitably thin tube (brake tube, thin fuel hose...) to your vacuum and suck as much out as you can. I would then spray penetrant in, turn engine over by hand and vacuum again. Then check with camera and if still any debris, repeat.
I agree with the vacuum advocates. WD-40 was originally developed to displace water ("WD" = Water Displacement). Vacuum, spray a copious amount of WD-40 into the cylinder and vacuum it out. Repeat as many times as necessary until the piston/cylinder walls look clean. I wouldn't turn the engine over until I performed this procedure.
Vacuuming up combustibles/petroleum solvents can, if conditions are right, ignite it within the vacuum’s motor and explode, rendering the vacuum useless (among other greater risks)....been there done that with a spray penetrant before. An oil siphoning tank like the Mity-Vac 7200 might be more appropriate if a combustible solvent is going to be used.
I think you guys are overthinking this. As long as there isn’t so much water as to cause hydraulic lock, i.e. more than the capacity of the combustion chamber, whatever is in there is just gonna get vaporized as soon as you fire it up
How long’s it set with water/rust in the cylinders? I would opt for caution, penetrant in the cylinders for a few days and turn engine over by hand, then risk breaking a stuck ring and scoring cylinder walls. just my 2cts.
He said he just pulled the plugs and it got in there so we're not talking about anything like that. Any little particles or remnants of rusty water aren't gonna last past a couple of cycles. it will all get vaporized.
He could "see grit" down the tubes and the water in the cylinders was "rusty" so it might be more than just water.
Regardless there is nothing you can do at this point by probing in there other than possibly wash or pack whatever material it is down between the piston and cylinder wall or maybe even lose a part of whatever it is you're sticking down in there to try and "fix" the problem and thus creating a new problem. If it's grit, it will get vaporized during combustion, I say leave it where it sits and don't disturb it. At least that's what I would do.
