What should I use to patch missing mortar between my foundation blocks?

Before I purchased my home it had been empty for a long time and at one point the basement had been flooded up to the basement windows with water. I did not know this when I purchased the house. Anyway, I can see daylight through the basement walls from the inside looking out, between the cement blocks. What kind of morter or whatever should I use to patch and plug the holes?What should I use to patch missing mortar between my foundation blocks?
Clean away any loose mortar. Use prepackaged mortar mix that you can get at any home improvement store. Wet down the area you are working in and use the edge of the trowel to force mortar between the cracks. This is called tuck pointing.


Wetting down the block prevents the dry block from sucking all the water out of your mortar mix making it less strong.





Strike off the joint with a rounded tool to make it look like the other stable blocks. Do this on both sides of the block. It is time consuming, but will be worth your effort.





I would so a small section at a time rather than disturbing all of the block at once.





Good luck!What should I use to patch missing mortar between my foundation blocks?
If you can see daylight between the bricks in your basement, call a contractor immediately. I think there is a major issue with the foundation of your house, it may not be safe.
1. As Ben said, have it checked by a professional.





2. Chisel away any loose mortar from the cracks in the blocks and replace it with a portland based cement.
well i can tell you that that tuck pointing an empty joint is tough especially for someones thats never done it b4. take a bit of fiberglass insulation, stuff the joint 'til its about 3/4 to the outer part of the joint. any hardware store will sell caulking specially made for your project. ask them, they ll point you the way. you need no special tools other than a caulking gun. if you find that your fix has separated again, get it checked immediately. if it doesnt move through a winter season, chances are its done moving for now.----------whoever gave me a thumbs down doesnt know their *ss from first base. mortar caulking is easier and neater than anybody can dream up in here