WVO and ring coking

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11-30-2009, 12:54
Kmehr

WVO and ring coking

Here is a question for all you WVO users. I have a greasecar/custom kit in my truck and it runs great on both diesel and WVO. I only have put maybe 5000 miles on wvo though.

While poking around on the internet, I have come across several sites that talk about the need to get WVO way hotter than our grease car type systems get it. They are saying 230 F is the minimum to get WVO to diesel viscosity and avoid piston ring coking, poor atomization, cylinder wall wear and premature engine failure. Makes sense to me, if the info on viscosity is legit. Their solution is to use injector line heaters like fattywagon.com sells.

take a look at
http://voconversionbasics.websitetoo...ost?id=1644578

and

http://biodiesel.infopop.cc/eve/foru...51/m/725107971

Thoughts?
12-01-2009, 09:48
crashz

I would be concerned with the high heat in regards to the IP, injectors and return lines. This is the main reason I've been working on test batches of home-brew biodiesel. The heaters draw lots of juice, and may be deterimental to the fuel system.
12-01-2009, 10:13
Kmehr

Well the proposed injection line heaters are placed on the metal injection lines right before the injectors so it would be after the IP.
12-01-2009, 17:56
Basshopper

Quote:

Originally Posted by Kmehr

Here is a question for all you WVO users. I have a greasecar/custom kit in my truck and it runs great on both diesel and WVO. I only have put maybe 5000 miles on wvo though.

While poking around on the internet, I have come across several sites that talk about the need to get WVO way hotter than our grease car type systems get it. They are saying 230 F is the minimum to get WVO to diesel viscosity and avoid piston ring coking, poor atomization, cylinder wall wear and premature engine failure. Makes sense to me, if the info on viscosity is legit. Their solution is to use injector line heaters like fattywagon.com sells.

take a look at
http://voconversionbasics.websitetoo...ost?id=1644578

and

http://biodiesel.infopop.cc/eve/foru...51/m/725107971

Thoughts?

That would be too hot. Thier are several factors that can cause coking. Early switching before your engine is up to full operationg temp, VO not up to temp, and too short of purging. I would suggest you get a heat guage and check what the temp is of the Vo before it hits the IP> I have had 2 trucks with Greasecar kits and the first one I did add a Heat therm inline before the IP for additional heat and on my D max non is needed. Between both rigs i have over 190000 miles on VO without any issues.
12-01-2009, 18:06
Kmehr

I have a heat gauge that measures the temp of the fuel right as it comes out of the filter (so pre IP and injectors) and it regularly stays at 135-150 without using my veg therm(electric inline heater). I have the Veg therm right after the fuel pump so it gets additional heat before the IP. I am going to move the temp sensor to right after the fuel pump to get a closer reading on what is going to the injectors. I have been very satisfied with how my truck runs on WVO on all but big hills at highway speeds (starts to miss and chug if I don't lift my foot a little doing 75).

However, the main thing I am asking here is how much heat do we really need? Coking the rings and causing big problems would really suck. Is the difference in viscosity of the WVO at 140 and 240 really significant?
12-01-2009, 18:14
Basshopper

180 to 190 Deg with your veg therm it will get thier. In regards to running your 6.5 under load I had he same issue Need a lift pump to compesate for that and it solved the problem. If you search the greasecar forum on 6.5s you will see lot of info on it including my 99 burb. I would not worry about coking. Sounds like you are doing things correctly. One tip I got a grill cover for the winter from Cabelas and that really helped on faster heat up and higher VO temps. Good luck
12-01-2009, 18:21
Kmehr

thanks, I think I have seen your burb on there quite a bit, I have actually posted on that forums with my various install issues haha. I actually have the Pureflow technologies Raptor pump, which provides tons of flow and I still get the chugging. I put a t valve in my fuel line after the raptor with a ball valve on it to i can purge the air out. No matter what I seal or how long I run the pump (hot wire the raptor and run a clear hose back to the tank) I still have air bubbles. Think thats the issue? any suggesstions on how to fix it?
12-01-2009, 18:31
Basshopper

Quote:

Originally Posted by Kmehr

thanks, I think I have seen your burb on there quite a bit, I have actually posted on that forums with my various install issues haha. I actually have the Pureflow technologies Raptor pump, which provides tons of flow and I still get the chugging. I put a t valve in my fuel line after the raptor with a ball valve on it to i can purge the air out. No matter what I seal or how long I run the pump (hot wire the raptor and run a clear hose back to the tank) I still have air bubbles. Think thats the issue? any suggesstions on how to fix it?

IT could be the issue I would track that down. More likely is unless you have at lease 20lbs of pressure on the HIH greasecare supply line you wont' get enough flow to prevent the stalling. THat is what I discovered on my burb I could run up to 100 towing my boat with no issues. I would also check your tank to make sure you vent is working so you don't starve from not enough air getting into the tank to alow fuel flow. Try taking off the fill cap and check it with it off.