Timer cards and the smell of veg

[lancaster,pa]

I have my purge and run cards set to 11 seconds and 58 seconds respectively. I'm still smelling veg at the tailpipe near the end of the 58 second run time. Could it be that the 7.3 is burning pure diesel at this point but that the exhaust from veg is still in the muffler and other parts of the exhaust system and takes some time to clear?

I don't want to harp on the settings of the timer cards, but especially with colder weather on the horizon, I want to make sure I am starting up on pure diesel the next day (cold starts on veg are bad). - Patrick

[Jack_Toepfer]

Have you guys revved the engine at all after the key is out?

If my timer doesn't work perfectly... I'd have no problem throwing my tuner onto the smoke tune and goosing it for a second. The truck will have no choice but to dump all sorts of #2 into the motor. You know how little fuel these things consume at idle. Thats probably a short term solution though. I'm probably going to do it anyway... throw some french fry smell into the air just before I get out.... fat chicks will love me.

[Marv]

I've been using the "stomp the go-pedal" method ever since I got mine up and running and so far it's working fine.

I occasionally smell a hint of vegi in the mornings, but not that often.

Haven't had any hard starts either, so I guess I'll just keep doing what I'm doing.

[Clay]

Marv, what is your purge timer card set at?

As far as the opriginal posters question, if you are purging 11 seconds, i would think that should be good, do try reving it once before you exit the truck and then see if your still smelling french frys.

[Marv]

Marv, what is your purge timer card set at?

As far as the opriginal posters question, if you are purging 11 seconds, i would think that should be good, do try reving it once before you exit the truck and then see if your still smelling french frys.

Clay, I'll have to check. It's on my to do list for this weekend. I saw James's post on the purge time, so I planned on checking it. I'll let you know what it is.

[Allofus123]

Smelling VO does not mean you're burning it. I would expect to smell it after as much VO exhaust has passed thru. It'd be like taking a drinking glass and drinking 5 beers in it then drink a glass of wine out of it.... there's still going to be a beer smell.

[FastCote]

Smelling VO does not mean you're burning it. I would expect to smell it after as much VO exhaust has passed thru. It'd be like taking a drinking glass and drinking 5 beers in it then drink a glass of wine out of it.... there's still going to be a beer smell.

Beer analogies. FINALLY, someone speaking in a technical jargon I can understand!

[Clay]

Smelling VO does not mean you're burning it. I would expect to smell it after as much VO exhaust has passed thru. It'd be like taking a drinking glass and drinking 5 beers in it then drink a glass of wine out of it.... there's still going to be a beer smell.

thats an interesting analogy...after i drank 5 beers i could'nt tell what i was smelling...

[Jack_Toepfer]

I thought he was going to talk about drinking 5 beers, then a glass of wine... and then smelling 5 beers in the exhaust... thats my wife's primary complaint.

[Marv]

I thought he was going to talk about drinking 5 beers, then a glass of wine... and then smelling 5 beers in the exhaust... thats my wife's primary complaint.

Haha...I was waiting for someone to say that. It's not so much that you smell it then but later!

[lancaster,pa]

Reving the engine seems to work well for people that can do this. However, my 00 won't rev after I turn the key off while still running in auto shutdown (others also reported the inability to rev with the 99 to 02 model years).

The beer analogy makes sense to me. However, I am also experiencing rough idle when starting up the next day. I was running on straight diesel for about a week and didn't experience any hard starts or rough idle.

Seems like there is some veg left in my engine after shutdown. Any thoughts on increasing purge or run times or any other ideas to diagnose the problem? Thanks. - Patrick

[Allofus123]

I was dealing with rough starts and think I've finally got it under control by increasing my purge to around 10-11 seconds. I had my run time over 2 minutes and that didn't take care of the rough starts but as soon as I turned the purge time up (it was at 8 seconds) no rough starts the past 3 days.

BTW, I have a 2002 F250 and I'm able to rev after turning the key off.

[lancaster,pa]

I was dealing with rough starts and think I've finally got it under control by increasing my purge to around 10-11 seconds. I had my run time over 2 minutes and that didn't take care of the rough starts but as soon as I turned the purge time up (it was at 8 seconds) no rough starts the past 3 days.

BTW, I have a 2002 F250 and I'm able to rev after turning the key off.

Allofus123,

Thanks for the info, it was a help. What did you settle on for a run time after adjusting the purge to 10-11 seconds? Also, I should have said the 99 to 01s don't seem to rev after turning the key off (you and others have said that the 02s do rev). - Patrick

[Wilson]

Kind of embarassing, but can someone tell me exactly what the purge does? That is the only piece I don't fully understand. I think it just purges the line of veg?

but electrically I am wondering how it works..

And what would one use the manual purge switch for?

[Elvia]

hear is a quote from Fordnut74, one of the owners. Look under general discussion, please explain the difference between purge and run time. Post # 26. Good info there.

From Fordnut74
Let's see if I can explain this without confusing people. The purge solenoid in the V3 is a "normally closed" 2 port valve. So under ALL conditions except for automatic shut down or manual purge it is in the closed position. Since there is only one fuel line feeding the engine, that means you can only purge diesel if the system is off. With the system on you will only circualte WVO back to the WVO tank. In the V3 there is a paralell path connected to the outlet of the V3. So for example, if you are on Diesel only and you push the purge button, what happens is the purge solenoid opens and creates second path through the V3 back to the return line. This path bypasses evrything else in the V3. And there is an orifice in the manifold built into the return line so that when the purge solenoid activates, there is still a restriction in the flow to prevent the engine from losing all fuel pressure as this could be damaging. So what that amounts to is with a fully warmed up system running WVO with ~70psi of diesel pressure you will get about 1oz per second of bypass. This can vary quite a bit based on grade of oil, temperature of system, length of hoses, etc.

DO NOT attempt to calculate how much time or fuel it takes to get diesel out of the return on the V3. THis process may work with the standard systems but unless doen right will give you completely false readings on the V3. In order to get an automatic purge sequence initiated the system has to be on. Well when the system is on, there is a small amount of constant return to the tank that is part of the air seperation(what allows you to not have to manual purge for new filters). And because the engine is a dedhead design fuel system, even after you switchover to WVO, it takes time for the WVO to work it's way up the fuel line, to the engine and through the rails displacing all of the diesel. So until ALL of the diesel has been displaced, you will get a faulty reading trying to determine the volume of fuel required for a full purge.

To simplify, just because the system has been on for 20 seconds does not mean you have displaced all the diesel in the fuel system yet.

I know all of this may sound complicated, but it really is not. It is just different than the norm and incredibly reliable. How many of you have ever had performance or driving issues? or ever been stuck alongside the road asking WTF? Hope this helps a bit??