Time to do a thorough undercarriage cleaning. Best product(s) and techniques suggestions greatly appreciated! Thanks!

A lot of citrus degreaser and scrubbing. See this thread for inspiration: http://www.914world.com/bbs2/index.php?sho...amp;hl=targa72e

EDIT: Regarding dry ice blasting, it works great (particularly good at brightening alloy components) but it is really expensive. I recently had a mag case done along with a few other aluminum items, cost was $400 bucks.

A complete 993 Turbo undercarriage was being done at the time, jobber told me it was $1600. Yikes. Scrubbies and citrus smells like a better option. Plus, when you're done sit back with a cold one and admire your efforts.

There has been some discussion of dry ice blasting, .... try google. I have used 3000 psi power washer with some success

Steam pressure washer. The kind that used diesel fuel to heat the water. The steam melts off grease and grime. With or without solvent. I thought it worked almost as good as dry ice blasting. You might be able to rent a unit. They are expensive to buy but I used to use one at the Porsche shop and it was pretty great.

Whatever you decide to do, get a cheap tyvek suit with a hood and wear a face shield. Then you can really get into it without splashing solvent, steam and grit in your face or skin.

I saw this six in person..very clean , underside,,
https://www.youtube.com/watch?v=rYtQQBYdMQo

https://www.youtube.com/watch?v=rYtQQBYdMQo

My 1st 1973 914 Porsche I had the undercarriage media blasted, prepped, primed, chip guarded and then painted. That job cost around $4,000 to be done professionally. Great job but expensive. I decided to do my 2nd 1973 914 by hand and I won't lie it is a big job. I did not have access to a rotisserie which is the correct way to do the job but I have a 4 post lift so I could get under the car. First thing I did was to degreaser with a power washer. The factory undercoating is hard and dry but I have great luck removing it with a pneumatic scaler. A scaler has a number of oscillating steel fingers that chipped away the old undercoating and paint. My problem was the aftermarket style undercoating, like Ziebart, which is still soft. That crap I had to scrap by hand with the help of a propane torch. I used solvents and a red scotch pad once I had most of the undercoating off. After all of that was done I wired brushed the complete undercarriage, wheel wells, engine bay and the two trunks down to bare metal. Then I did my metal repairs, then I used a metal cleaning solution (adds a zinc phosphate coating and some flash surface rust which helps the Encapsulator to etch in), followed by Eastwood Encapsulator (effectively a primer), followed by a light coating of chip guard and finally 3 coats of an industrial single stage paint. The 2nd 914 cost under $1,000 but consumed over a hundred hours to complete. It is something you can do yourself but it is a dirty, boring and time consuming process. attachmentid=847530] Click to view attachmentClick to view attachmentClick to view attachment Click to view attachmentClick to view attachmentClick to view attachment Click to view attachmentClick to view attachmentClick to view attachment Click to view attachment Click to view attachment

Looks great, but is it worth the time? We have a local dry ice blasting guy I will be trying his service at some point. He has quoted in the $800. range for the underside.

You guys are comparing two different things. One is cleaning the existing surface, the other is taking down to bare metal and refinishing. Both have their place but apples to oranges.

If your not worried about the paint...I bought the extended angle grinder and mounted a wire wheel. It only took four hour to do the entire bottom of the car. It took off all old undercoating and some of the paint...but really a nice start point. Also it was the best tool for getting up into the inner fenders to get rid of all the thirty years of junk. After that the inner fender looked so good I made inner fender liners to keep all the stuff out. MarkClick to view attachment

All: When we bought the 74 914 I found a blaster who would come to my shop to dry ice blast. I tented the car on my lift and was able to remove the wheels and brakes.
He came out and spent the day and I am very pleased. A few photos are attached.
I had just removed carpeting from one of our offices and put it on the floor under the car. Cryocleaning messy! When he was all finished I just rolled up the carpet and tossed it in the dumpster. However, the rest of my shop was coated with black dust that is like soot. It's hard and dry so it didn't stain anything but it still took me two days to clean up.

This year we bought an 80 SC and the dry ice guy now has his own shop. Win!! I took the car to him and he did take the wheels off. Unfortunately, he really didn't take his time and left a lot of undercoating up in the wheel wells that I can't imagine how I'm going to remove.
The price for the 914 was $2300. For the SC he charged me $2800 even though he didn't have to travel, and he forgot to clean the wheels he took off.

Bottom line if that dry ice blasting is terrific. But, you need someone who is reputable.

PS: I really struggle with attachments on this forum, sorry if I sent any dups. PM me for any questions.
Rob

Any recommendations for a good solvent would be appreciated.

Sounds like my guy here is a bargain at $800. I have yet to give it a try though

I'll try againClick to view attachment Click to view attachment Click to view attachment Click to view attachment Click to view attachment
WTF, I put five different photos in and the site named them all the same.
Way too difficult to navigate. PM or email me and I'll send pictures.

Best solvent for oil based products is Xylol or Xyelene, different names for same product. Will not attack paint. Used to remove tar from exterior paint. Used it to deal with the undercoat on a 911.



Any recommendations for a good solvent would be appreciated.
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