Exhaust pipes on a KR

[Steve Meltzer]

Please excuse my paranoia with this car, but I'm afraid to do anything that might undo the great restoration that was done in front of me. So, with the car up, I see this black stuff that looks like a bit like a melted black plastic bag on one of the exhaust pipes. It's really pretty flat with respect to the pipes surface, and looks like it would be difficult to remove. I assume that it does not belong there, but before I start trying to scrub it off I thought I'd better check with the pros. Thanks again for helping me as I learn more about these cars. Steve

[Bob Gaines]

That looks like what many times happens when moisture in the exhaust system mixes with soot on the inside lining of the pipe that is generated by the exhaust. The black liquid bleeds out between the exhaust pipe connections during the course of the engine running. The black liquid will stain the metal pipe if left too long . Yes you can take it off . I would try lacquer thinner or other solvent first but would refrain from scrubbing it with something course because it will leave scratches in the metal finish of the pipe. This is a problem with show cars that must be cleaned trying to present themselves as fresh from the dealer condition. Not so much with a car that is driven for pleasure.

[Steve Meltzer]

Bob, thanks again for the information. I never would have thought of that chemistry. I tried lacquer thinner earlier with really minimal effort and therefore, minimal success. I'll try again tomorrow. May try goof off or one of the other citrus based cleaners. thanks for your help. Steve

[Bob Gaines]

Steve ,it could of course be the remains of a plastic bag that stuck to the hot exhaust pipe and melted. If that is the case you will have to use a heat gun to soften the plastic before trying to wipe off with a thick rag . As a alternative I would get some of the hard plastic chisels used on automotive interior trim made out of Delron that are cheap at Harbor freight. Those hard plastic tools will not scratch the metal and will probably stand up long enough to get the melted plastic off before they themselves succumb from the heat. 

[Steve Meltzer]

Bob, thanks again for your suggestions. I worked a bit on this this morning and made some very slow but steady progress using the barbecue grill goof off. I have those interior trim piece scrapers and I may try them as well. I'll give it another go tomorrow. In the meantime, do you have suggestions for removing rust without removing any parts. I really don't want to even fine sand these things, but there are areas that need attention. Thanks again, steve

[Bob Gaines]

Bob, thanks again for your suggestions. I worked a bit on this this morning and made some very slow but steady progress using the barbecue grill goof off. I have those interior trim piece scrapers and I may try them as well. I'll give it another go tomorrow. In the meantime, do you have suggestions for removing rust without removing any parts. I really don't want to even fine sand these things, but there are areas that need attention. Thanks again, steve

There are numerous liquid rust removing products . Applying them can require some creative usage . example-soaked rags held in place with clear plastic food grade cling wrap. Keep in mind that the rust remover can take off a finish like zinc dichromate (gold). So that there is no unrealistic expectations this is a ongoing maintenance issue for show cars being driven. I have seen Show cars that are driven maintained successfully . It just requires attention.

[Steve Meltzer]

I can say with 100% certainty that this car will never be shown under my stewardship. However, I do want to maintain it in as nice a condition as possible. It will be somewhat easier now that I understand where the jacking points are! Thanks again, Bob. Steve.