Vaporizor clog
Posted by:
EBG (IP Logged)
Date: August 18, 2008 03:29AM
Hi all,
I seem to be having a chronic vaporizer clog issue on my 735 Stanley with a Cruban burner and pilot. I started off this season burning a mix of diesel and gasoline, about 60/40. I have had clogging issues all year. I switched out my vaporizer last winter because my old one had clogged up and cemented the cable inside it. I kind of made some design changes to try to address this issue. The first new vaporizer that I made is about 7' long (total length including the 8" stainless steel hot dog). I made the vaporizer loop of mild steel 1/4" Sch 40 pipe bent on my forge using a sand filler to make sure I did not collapse the tube. It was kind of difficult to get all the sand out but I think I eventually got it all out. Anyway with this set up if a ran a cable it clogged in about 10 miles, without a cable it clogged in 20 miles. I switched to straight #2 Diesel to see if that would help and had similar results. So then I bent up a vaporizer that was 1 foot shorter because I thought I was getting the fuel too hot. This time I made it about 30 miles without a cable until I got significant clogging. It always seem to clog near the junction of the loop and the hot dog. This joint does not leak and last time I tried covering it with ceramic insulation to try and keep it cooler. The vaporizer is about 1/2" to 1" above the burner grate.
So, am I headed in the right direction, should I take another foot of length off the vaporizer (this would mean a total length of 5 feet)? I know I could probably just switch to Kerosene and avoid some of this issue however I am trying to make this car run on readily available pump fuel so I can take it some distance from home where I would not be likely to find a source of Kerosene. Right now when things are burning well I do not have a smoky fire even when relatively cold, I can fire it up without using the start up valve and not have a smoky fire. My fuel pressure is 150 lbs. I assume that this means that the fuel is getting very hot right from the get go and when I really get going it gets too hot and cracks leaving the carbon residue that clogs things up. Is it just impossible to get a clean vaporization of #2 Diesel?
On the plus side my pilot now seems to be working flawlessly (I probably shouldn't have said this!) now that I have switched to a # 76 jet and 6-8 lbs of pressure. It does get blown out by the burner when it is working a full tilt unless I have my stack blower on. It relights as soon as the burner pressure drops as the burner cycles off. Thanks, Eric