I wouldn't take the chance, to be honest. I know a few people who have ruined their very expensive machines by making homemade laundry detergent, so I'm loathe to make any suggestions for anything other than stuff that is indicated for your specific machine. (I've written more about this topic in this post - Ramblings: Making your own detergents...Make the recipes from the other blogs at your own risk.)
In this Weekend Wonderings post, p asks: Do you have any idea why is it that coconut oil alone feels greasier than coconut oil in a lotion? I've noticed this as well, and for a while I attributed it simply to quantity. I.e. even if you're trying to use very little straight coconut oil, you still will probably end up getting more coconut oil on your skin than if you use a coconut oil lotion... but really that doesn't seem right to me.
Oils on their own will always feel more greasy than in a lotion for a few reasons. The first is sheer quantity, which you note. If you put 5 grams of coconut oil on your skin, you're using 100% or 5 grams of coconut oil. If you put 5 grams of lotion with 10% coconut oil on your skin, you're putting 0.5 grams coconut oil on your skin, which will feel much less greasy just because there's less.
Secondly, in lotions we can modify the skin feel by including water, water substitutes, emulsifiers, fatty alcohols and acids, oils, esters, and just about everything else. Adding something as simple as 2% IPM can reduce greasiness or adding 2% cyclomethicone can increase a feeling of powderiness. Choosing your emulsifier will alter the skin feel as well - Incroquat BTMS-50 and Ritamulse SCG will produce a drier feeling lotion, while Polawax and e-wax NF will produce a slightly greasier feeling lotion.
I do a lot of work on creating drier feeling lotions in the products for men section of the blog, if you're interested in learning more!
If you're curious, try mixing a bit of coconut oil with a drier feeling oil and see the difference. Take 10 grams of coconut oil and add 1 gram hazelnut, macadamia nut, grapeseed, borage, evening primrose, or pomegranate oil and see how it feels. Or try an ester with it - say 1 gram IPM, IPP, C12-15 alkyl benzoate, cetearyl ethylhexanoate, or ethyhexyl palmitate - or cyclomethicone. Now add a bit more and see what it feels like. If you keep going and end up with 10% coconut oil to 90% other oil, you can see how the interaction between two oils change with the percentages.
Want to get to know your oils and butters better? Check out the recent Newbie Tuesday series!
As a quick note, I have something like 2390 unread e-mail messages right now, and I'm working hard to get through them, but I can't promise I'll be able to get to your question any time soon. I really recommend doing a search for what interests you rather than waiting for me to respond as you might be waiting a very long time. I'm doing what I can, but between life, school, work, youth programs, time at the gym, and the attempt at having what might be considered a social life, I'm finding it hard to spend the time I'd like to answer messages. (When I get computer time, the blog has to come first!) This isn't to say that I won't answer e-mail - I love receiving your messages! - but I can only do what I can, and every day I'm falling further behind. I really encourage you to read the FAQ and do a search to see if I've addressed your question in the past. (I have almost 2000 posts on the blog! Can you believe it?) I find it easier to get to the comments than e-mail (not sure why), so posting one on a related topic will probably get a response from me sooner than an e-mail.
Please don't ask me to duplicate products - I've said it many many times, but it's simply no fun for me and I think I've offered enough information for you to figure it out.
Join me tomorrow for more commenty fun!