Forum Discussion

RColorado's avatar
RColorado
Explorer
Aug 05, 2025
Solved

Dicor Lap Sealant Question

I need to fill some cracks in the sealant on my roof. I've done this before but can't remember what product to use to clean the area of the cracks before putting new sealant on. 

I thought I had used Mineral Spirits (paint thinner) in the past, but the Youtube videos I looked at today only mentioned denatured alcohol.

I've got plenty of paint thinner on hand - will taht work or do I need to buy some denatured alcohol?  

Thanks!

  • Grit_dog's avatar
    Grit_dog
    Aug 05, 2025

    If you use mineral spirits (paint thinner) you may as well just use WD40. Both leave an oily residue. 
    Use alcohol, wax and grease remover (for paint prep), lacquer thinner, brake cleaner, etc. I wouldn’t use anything hotter than those solvents. 

5 Replies

  • StirCrazy's avatar
    StirCrazy
    Moderator
    Aug 07, 2025

    use white gas, that's what all the dealerships I have talked to around my area use.  so basically Colman camp stove gas.  I did mine and put some in a spray bottle, spray some on wipe it off with a rag wait a few, then do the repairs

    • way2roll's avatar
      way2roll
      Navigator III
      Aug 06, 2025

      So the new sealant sticks. Putting sealant on dirt/grime/mildew won't seal very well. 

  • way2roll's avatar
    way2roll
    Navigator III
    Aug 05, 2025

    I usually clean the entire roof and then come back over the seams with alcohol. 

  • Grit_dog's avatar
    Grit_dog
    Navigator II
    Aug 05, 2025

    If you use mineral spirits (paint thinner) you may as well just use WD40. Both leave an oily residue. 
    Use alcohol, wax and grease remover (for paint prep), lacquer thinner, brake cleaner, etc. I wouldn’t use anything hotter than those solvents. 

About DIY Maintenance

RV projects you can tackle on your own with a few friendly pointers.4,387 PostsLatest Activity: Aug 18, 2025