1987 Chevy Bus WVO conversion questions

A description and pics of your SVO WVO Vegetable Oil conversion, help the next person who gets that model.

Moderators: SunWizard, coachgeo

1987 Chevy Bus WVO conversion questions

Postby Lighthousebus » Tue Mar 06, 2012 12:21 pm

This was split from 1995 Dodge Cummins 4x4 WVO conversion, FPHE, 3 valves since its off topic to that thread.
hello,
first of all great system. been running wvo for years but i have to say this is the best routing I've seen so far. Anyways, I've done a number of conversions and the last three have been modified versions of your system. The ones I've done have been on school buses and one van. The biggest difference is the size of my coolant loop. reason being is because my systems have an on board cleaning rig in a third tank. Consists of a second FPHE (pre centrifuge), another tank heater and another heated filter. On my veg system its almost identical to yours as far as a coolant loop however its quite a bit longer because its a bus and my tanks are mounted 15' or so from the engine. What I'm getting at here is I'm having heat problems. The engine is an 8.2 detroit and I tapped in out of the top of the water pump going to my front cab heater. Which is exactly the same as another bus I did and it worked fine. On that bus i used cheapo utility water pumps to boost the coolant loop. It worked other than the inevitable failure of the cheap water pumps doing a job they weren't meant to do. On this new bus however I have had heat problems from the start. I first tried using a more sturdy coolant booster pump made by thomas buses. That thing was so weak that I was maybe getting my loop up to 120 on a load. So being on a time crunch for a tour I reverted back to the cheapos that i know best. Long story short I've now installed 5 cheapos in a matter of 4 days. they have either fried or a cheap gasket on the bottom has given way (probably depending on how good the gasket is). I have them under warranty so I've only paid for one of those pumps. ($40 at harbor freight). When the pump is working my heat gets good. One lasted for about 6 hours driving and I ran on veg for that time. The rest haven't lasted at all. As far as I know those outs from the water pump are post thermostat however it always worked on my old bus and the harbor freight pumps would last 6 months or so. My theory is the thermostat on this new bus works differently than my old one and on this one its not allowing my pump to push and pull at certain temperatures and they are overworking themselves. I have a solid booster pump being shipped to me made by groco but im concerned there is a fundamental problem with my coolant loop that a heavy duty pump wont solve. I know I could solve this if I had some time to do tests however I'm on tour with a band and the group has to make certain destinations. As of now we are running on diesel and i'm troubleshooting in parking lots and in front of venues. Any advice or ideas would be greatly appreciated. The two buses I'm comparing are a 1987 chev with an 8.2 rebuilt in 96' (old one that worked) the new one is a 1989 chev with an 8.2 Rebuilt at some point not sure when... Thanks for reading!
Lighthousebus
 
Posts: 7
Joined: Sun Jun 19, 2011 2:12 pm

Re: 1987 Chevy Bus WVO conversion questions

Postby SunWizard » Tue Mar 06, 2012 1:45 pm

If you tapped in where you should: where the cab heater is for both in and out, there is no thermostat to block flow. You could check this by unhooking the hoses, putting them in a large bucket, and cold start the engine. There should be flow, and it should be a good amount of flow even without a booster pump.
YVORMV - Your veg. oil results may vary.
95 Dodge Cummins 4x4 SVO WVO conversion.
81 Mercedes 300D- stock and happy on V80/D20 blend.
Low fossil net zero house- 100% solar power and heat.
SunWizard
Site Admin
 
Posts: 1720
Joined: Mon Dec 11, 2006 2:53 pm
Location: N. Colorado

Re: 1987 Chevy Bus WVO conversion questions

Postby Lighthousebus » Tue Mar 06, 2012 5:39 pm

hmm yeah i'm not sure man, what I do know is that there is a line going to a heater core by the feet of the driver and a line returning. I've done that test with this bus and the last and nothing flows till you hit the gas and you hit maybe 1500 2000 rpms. Ill post some pics later of my pump ports.
Lighthousebus
 
Posts: 7
Joined: Sun Jun 19, 2011 2:12 pm

Re: 1987 Chevy Bus WVO conversion questions

Postby Lighthousebus » Wed Mar 07, 2012 11:43 am

Image the send is the port coming strait out the top on the right. It returns right below that 1 1/2" hose in the bottom right of the pic. This was going to a front cab heater. and from the tests I did it seems it only flows after a certain rpm/temp.
Lighthousebus
 
Posts: 7
Joined: Sun Jun 19, 2011 2:12 pm

Re: 1987 Chevy Bus WVO conversion questions

Postby SunWizard » Wed Mar 07, 2012 12:21 pm

Lighthousebus wrote:It returns right below that 1 1/2" hose in the bottom right of the pic. This was going to a front cab heater. and from the tests I did it seems it only flows after a certain rpm/temp.

Too hard to tell from that pic since the return isn't visible. Normally it comes from the head, returns to the water pump. There is a big difference in whether it flows at certain temp (thermostat is blocking flow = plumbed wrong), or a certain RPM (weak water pump?, restricted someplace?).

Did you put a ball valve on the line so you can control how much goes to the cab heater versus the WVO side like on mine? Did the cab heater work OK before you cut into the lines?
YVORMV - Your veg. oil results may vary.
95 Dodge Cummins 4x4 SVO WVO conversion.
81 Mercedes 300D- stock and happy on V80/D20 blend.
Low fossil net zero house- 100% solar power and heat.
SunWizard
Site Admin
 
Posts: 1720
Joined: Mon Dec 11, 2006 2:53 pm
Location: N. Colorado

Re: 1987 Chevy Bus WVO conversion questions

Postby Lighthousebus » Fri Mar 09, 2012 1:36 pm

SunWizard wrote:
Lighthousebus wrote:It returns right below that 1 1/2" hose in the bottom right of the pic. This was going to a front cab heater. and from the tests I did it seems it only flows after a certain rpm/temp.

Too hard to tell from that pic since the return isn't visible. Normally it comes from the head, returns to the water pump. There is a big difference in whether it flows at certain temp (thermostat is blocking flow = plumbed wrong), or a certain RPM (weak water pump?, restricted someplace?).

Did you put a ball valve on the line so you can control how much goes to the cab heater versus the WVO side like on mine? Did the cab heater work OK before you cut into the lines?

After some more tests and troubleshooting Ive found you were right that it is pre thermostat. It fooled me before because I think the water pump is pretty weak. I checked it on the return side at first and only waited 10 or 15 seconds before revving the engine assuming that I needed to heat it up. I'm not sure if that heater worked... never turned it on. Had the bus for about two days before tearing it out. I've got my heat up now but I'm basically forcing it to do what I want. ive got THREE booster pumps on there. I did pull some old manuel valve that was on the heater loop but it was stuck in the open position. However it was def a flow restrictor. Like I said I've got good heat now but I have to assume my water pump is either failing or incredibly weak to begin with. with no booster my loop is below 100. with 2 of the continuous duty ones that are kinda weak I get up to 130/140 and with the third cheapo harbor freight I'm 175ish... There are valves on the loop, both my buses seem to come stock with valves.
Lighthousebus
 
Posts: 7
Joined: Sun Jun 19, 2011 2:12 pm


Return to Veggie Oil Conversion Vehicle Database

Who is online

Users browsing this forum: No registered users and 0 guests