Cold Start Problems on a WVO rig

[Adam]

Mitsubc mentioned some of the cold start problems he has seen on some WVO rigs in his thread: http://www.delica.ca/forum/attention-wv ... -5008.html Seeing as that thread got side tracked a bit I thought I'd post my specific symptoms and see what the forum can diagnosis:

• *Incredible rough colds starts on diesel even after purging the engine
  *Even after starting there is hardly any power on diesel, once I warm the engine up a bit and can switch to Veg power improves dramatically, I'm guessing it has something to do with the two Aux fuel pumps I've added to the Veg lines
  *Starts fine on diesel if I plug in the block heater for an hour or 2

I've tried burning most of the diesel in the tank thinking that was too high a mix of WVO in the diesel tanks from the 6-port value, but after a 56L fill up the rough cold starts are just as bad.

My next option is to switch one of the Aux fuel pumps to the just before the IP supply so that it assists both diesel and WVO. The only reason I haven't done this before is because I was worried about hot WVO wrecking the pump.

Does it sound like a glow plug or IP issue? I have to take it up to CC Autos for a tune up this month anyway, but I was hoping to try to figure out the issue first and save Glenn some time.

[PlantDrive]

Hi Adam:
Sorry for helping sidetrack your original thread. I've just slapped my own wrist (it still smarts a bit, too, but I'll be ok).
Hard starting then no power on diesel....
Have you changed the diesel filter?
Glow plugs/Glow Plug Relay been checked?
Checked for air leaks into fuel system on diesel side?
Electric Pumps working? (I do not like them and they are not needed, I'd get rid of them).

[PlantDrive]

Oh, both pumps on Veg side...ok.


---
You can also check the diesel flow (and diesel filter) and the 6-port quite easily, to make sure that it is putting out the proper fuel per each valve setting...

Since you do have the dreaded electric pumps on there and they are still working, you could remove the line at the IP inlet, run it into a bucket, then put the valve on the diesel setting, check to see if you have flow and that it is diesel fuel by pumping the hand primer on the diesel filter ( much easier from driver's seat, get a helper for the line and bucket)

...then if that looks ok, it pumps diesel easily, say, switch to veg side..in that case you should see a change in colour and consistency of fuel, your electric pumps will be pumping it into the bucket in this case.

If you have good flow easily/quickly of both fuels doing this test, starting with a cold van that's been sitting a while, it's maybe glow plugs/relay or worst case a bad compression or pump timing or timing-belt-jumped-a-notch sort of issue...

[Adam]

I have 2 inline glass filters, one before the IP and one after and there doesn't seem to be any air bubbles in either in diesel or on WVO. I hesitate to think it is a diesel flow issue because I can run fine on diesel, once the engine is warm, whihc make me think it might be a glow plug issue, but I don't really have a good idea on how to diagnose that. I guess I could search the forum some, just haven't had a chance to devote much time to it with the kids, house building and job. It is almost easy to ignore when you have a work around like a block heater that you can plug in to solve the issue


What is the potential problem with the electric pumps? I installed them on the recommendation in Sliding Home. It sure made it easy to prime the WVO lines during the install.

[after oil]

a glow plug relay test:
attach the clip end to a ground,
turn the key till you hear the plug relay click on
touch the flat plate that connects the plug to see if there is current

a glow plug test:

remove the flat plate that connects the plugs.
with a 12v test light, attach clamp end to positive terminal on battery and touch each plug where the flat plate usually sits. if the plug works the light will come on

[delicat]

Adam,

To test your glow plugs it's quite easy. Remove them all and put a aligator clip on the tip of your glow plug and connect it to the positive of a battery while touching the side of the glow plug onto the neg. side of the battery post. The tip should glow red within a couple secondes.

If they are all good then it could also be your injectors. I had similar problems and once cleaning the injectors it all worked like a dream again.

I'm not sure why it's happening, that would be typical of the oil not running hot enough but we have the same system so who knows. I cleaned my injectors before leaving for my road trip across Canada and after about 5000km they need to be cleaned again (same symptoms). Kinda annoying!

Good luck!
David

[PlantDrive]

Ok, Adam, I did not catch that you are ok on diesel once it's running, I thought it was low power all the time which made me wonder.....Test plugs and relay.

My issue with electric pusher pumps is they are one more cost, one more thing to install, and you don't need them, and they have a tendency to fail within a year or two, and don't work at all (cheaper ones) if it's too cold and the oil is too thick. For priming a system initially, you can use a suction gun (cheap, looks like a grease gun), a MityVAc, an outboard motor primer, etc. and then after, at filter change time, if you clamp off the inlet line so the fuel does not drain back while you change the filter, you can just toggle the switch a few minutes while driving, bleed off air, and away you go.

[delicat]

Edward,

Does the fuel pick up location in the tank matters for having a aux. fuel pump? In my 1st set up the pick up was at the bottom but on my newer tank it's a more traditional set up where the pick up tube comes from the top and lowers down into the tank so that I avoid picking up dirt... Would that work without the aux. fuel pump?

My return comes just before the aux. pump (towards rear of van). What would improve by having my return between engine and wvo filter?