DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Plumbing (
-   -   working with cast iron (

ericadami 11-23-2008 06:28 PM

working with cast iron
So, I am trying to replace a pvc kitchen sink drain and the last elbow(which is a 90 degree long sweep) before the current drain runs into the sewer line is comprised of 2" cast iron. The 2" pvc drain pipe enters the female hub of the cast iron and is held in place by what looks like a mortar of some sort. The bottom end (male end) of the cast iron elbow also looks like it is held in place at the cast iron sewer main by the same type of mortar. I have not worked with this before, I have only really seen the old lead wool and oakum joints on cast iron, which is easy to remove. Basically I have to replace the cast iron 2" elbow so I need to get the elbow loose from the sewer main and want to do this without messing up the sewer main. How do I proceed removing this mortar or cement or whatever it is? Or would it be possible to cut the bottom end of the cast iron long sweep elbow a few inches from where it connects with the sewer main and couple it to PVC? Thanks, Eric

skyman 11-23-2008 08:31 PM

I think it would be better for you to just cut the long sweep elbow, and connect it with your PVC. It's not really legal considering you are not allowed to alter fittings in any way, but if you have no fear of an inspector coming in, I'd say go for it. It would be a lot easier!

I've never had to deal with this on the job, and if I did, I would have to do more than what I mentioned above. It's worth a shot.

ericadami 11-23-2008 09:04 PM

I am pretty sure that would work fine, but I could end up selling at some point, and I don't want to get hosed if we do end up getting inspected. What I also don't want to do is mess up the sewer line, and I'm afraid I could do that if I dont remove the cast iron elbow from the end of the sink drain properly. Good news is that its not a rush situation, so I have plenty of time to figure it all out.

majakdragon 11-23-2008 10:26 PM

I would bet that under the weird coating you are seeing, there is lead. Try tapping lightly with a chisel or screwdriver to see if it comes off. Someone may have had a leak and used some sort of masonary product to seal it. If you can remove the elbow, you can get a "donut" that changes the inside of the hub to PVC size.

ericadami 11-23-2008 11:20 PM

I do have the donut I need to adapt to pvc. I used a Dremel grinder to chip away a little of that masonry product around the base of the elbow and it does grind away, I just want to make sure not to damage the 4" sewer main, that be more than I'm ready to deal with at present.

majakdragon 11-24-2008 10:35 AM

If it is a typical cast iron elbow and hub, you should have a space of about 1/4" between the tow, inside the hub. Whatever method you use to remove the substance, stay close to the elbow and you shouldn't be damaging the hub.

ericadami 11-24-2008 12:42 PM

Thats what I am hoping, thanks for the info. I'll probably try to get back at it sometime during my long weekend thats coming up.

4just1don 11-24-2008 11:54 PM

sure somebody didnt goo across the top of the lead,thinking they were doing good to it?? Like silicone or sealant of some sort?? IF you drill a small hole on top it should be eaasy enough to seal and quit. if its masonry might need a cocrete bit. but you can cut metal with conc bit so take it slow and SEE. My bet is it is still leaded and oakum inside there.

ericadami 11-30-2008 12:26 PM

yep, the lead was in there down below the mortar, it took a bit to get through b/c I was being real careful not to crack the hub on the sewer main, but once I got down through it with a small sacrificial screwdriver, removing all the rest was relatively simple. Getting the donut fitting set in the cast iron hub with a new elbow was easy and the rest was pretty straightforward. The old drain had about 10 feet of 1.5" galvanized steel with 2 nasty elbows before it was adapted to 2" PVC then run about 25 feet to the sewer line. Judging by this and some of the other messy stuff I have run into in this house I am guessing some prior homeowner wasnt afraid of the crawl space but also wasnt particularly skilled down there either.

Anyhow, the new drain runs through a 1.5" white pvc Ptrap, merges with 1.5" black pvc tee, with 1.5" galvanized vent going up and 1.5" pvc going down into the crawlspace, adapts to 2" and runs ruler straight about 23 feet to the sewer line. According to what I've read 2" drain should drop about a quarter inch per foot of horizontal run, so my new line drops just about 5" for the 23 feet it runs to the main. The Ptrap holds water in the bend just as it should. The 1.5" vent runs to the roof solo and I have left this intact. I think its fine but being a total novice does all this sound ok? Thanks again for all the useful input, I'm pretty handy around the house but I'm fairly new to the plumbing thing....


majakdragon 11-30-2008 12:45 PM

Glad it all worked out for you. Sounds like you did everything right. Most people fear getting into plumbing problems, even simple things.

All times are GMT -5. The time now is 12:24 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1