I doubt it is cold grease. if the oil is flowable, it will run. The engine won't like it and you may do some damage by coking the cylinders/rings/injectors, but it will run.

Sounds more like you have a bad ground on the valves or still have air in the lines. Intermittent switch contact is also possible. Check valve operation by having someone switch the system with the key on, engine off.

VO-->D both valves click/actuate
D-->VO both valves click
VO-->supply valve only clicks

Pull your filter and see if there is air in it or watch VO tank for bubbles when purging for an extended time.

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sdeck

2003 Jetta TDI, GreaseCar kit, veg-therm std, TDIHeater, >20,000 veggie miles and counting!

"If you make it idiot proof, nature will make a better idiot"

Quote:
Originally posted by: skinnybones
going with the air leak theory: after the first switchover to grease(and subsiquent loss of power and stalling-out), i then restart on diesel(after cranking it for a bit and worrying that i am frying my starter), does it make any sense that once it is running again and at decent temp i am able to switch to grease with no problems(no loss of power, no stalling-out) and run on grease effortlessly? in other words, if there is indeed air leaking in on the grease side of fuel plumbing, why wouldn't this also affect operation when i am switched to grease and the vehicle is running fine?

i will try checking the filter for air, and am assuming you mean take the filter out of housing and dump oil from filter into something clear and looking for bubbles, right? will also try purging for longer than my usuall 60 sec. and look for bubbles in tank.
thanks for the suggestions.
I don't thihnk you need to dump the oil out of the filter, just check the level. it should be full enough to spill when you unscrew it, but looking for bubbles is not a bad idea, especially since you already have it out.

As far as hard to switch but then fine, one possibility is that a very slow leak or a leak on the pressure side of the IP would allow air into the system when the system is off. this causes the oil to drain to the lowest point, the tank. the air in the line makes it hard to run when you switch and when you switch to diesel or purge the air get pushed back to the diesel or VO tank (depending on which mode). since the leak is slow or since it now under pressure, it will either leak or allow very small amounts of air in. i would also check the filter seal since it could cause all these. You did grease it before installing right?

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sdeck

2003 Jetta TDI, GreaseCar kit, veg-therm std, TDIHeater, >20,000 veggie miles and counting!

"If you make it idiot proof, nature will make a better idiot"

Hi,
I've been having a problem for months now and haven't found the solution. I've been scouring the forums and these symptoms appear all the time but with widely varying diagnoses. I feel like I'm having the same problems as skinnybones. Hopefully more people with the same symptoms and all the advice out there might solve our problems better so thanks in advance to any advice.

I believe it's air at this point. I installed a small clear fuel filter in my veg line right before the valves to see if there was air in the line at that point. You can see pictures and a video of it running here: http://www.davauer.com/svo
The problem is, I don't know what it should look like so it doesn't really tell me if it's the problem. I'm assuming that filter should fill up with fuel and there should be no air or bubbles in it. As you can see from the pictures and the video, bubbles are constantly being formed as grease comes into the filter and it never fills to the top. I'm assuming there should be no air in the filter and therefore this test shows that the problem is air. Can anyone confirm this?

My symptoms are as follows: if I put in a brand new filter I get about 200 miles of smooth grease driving as it should be with no power loss. Then I start to get intermittent power loss and slow bucking. If I switch back to diesel it runs fine. If I leave it run for 10 miles on diesel and then switch back to veg I get another 10 miles or so of smooth running. I can do this over and over and get another 200 miles out of the filter.

I thought it was dirty oil/clogged filter at first because when I changed the filter I would get the smooth 200 miles. But it doesn't make sense because if it was clogged, it would stay clogged even if you switched back after ten miles on diesel. Maybe the air bubbles settle or something over the ten miles on diesel?

I also filter my oil through one 5micron filter and then heat it and filter it through the 5 lined with the 1. So 5+5+1 before going in the tank. I know the filters can get 2K plus miles on good filtered grease.

Again, I feel like the pictures of the filter should explain if that air is a problem or not. I just don't know what it should look like.

Thanks everyone for any advice.

Nat

I have a test that needs to be done. When you are ready to switch to grease (the system is hot) instead of switching, purge (which pushes any bubbles back into the tank with the use of diesel, then switch to grease. Of course the amount of miles driven prior to seeing grease in the IP will be after the filter and grease line have been consumed in miles (perhaps as many as 15) then tell me how the car is acting. What I am thinking is that after shut-down, air is pulled into your line as the diesel drains back into the grease tank (diesel because you purged prior to shut-down). When you switch back to grease, an air bubble in the line is making its way back to the IP after about 10 miles. Remember, purgeing does not run diesel into the grease filter, but only back through the line and to the tank.

Check this out and then let me know if anything has changed.