W124 300D Multivalve - fuel blockage.

[wastedisposal]

Just two weeks ago I have purchased the car of my dreams a W124 300D Multivalve, estate.
It ran on diesel without any problems, than I've filled it up with 70 litres of WVO and 5 litres of unleaded. The car behaved very well and I was enjoying the smell of Chinese food coming out of the exhaust. Unfortunately the next morning it refused to start. So far I have replaced most of my fuel plumbing, new pre filter and fuel filter and I am in process of removing the fuel strainer. Yesterday I've spent all afternoon removing the taw bar which was obstructing access to the strainer.
This morning I've ordered a new fuel strainer’s O ring and the 22mm Allen key from Ebay. I am hoping that after draining the tank and cleaning the fuel strainer I will be able to start the engine and run it on pure diesel until all the fuel leaks are dealt with.
Just yesterday a friendly car mechanic has suggested installing a Mercedes / MAN truck fuel filter on my car. Apparently standard Merc fuel filters can't cope with SVO / WVO. :fail
Any advice would be greatly appreciated!

 

[trapperjohn]

I'm sure our vegie pilots will be along soon.

 

[91dm]

I've never had a problem with standard Mercedes filters using veg oil so not sure about that advice.

 

[wastedisposal]

I am really hoping to run my car on 100% WVO during warmer months and 60%WVO + 40% diesel mixture in the winter. I am just concern that the engine will keep clogging up.

 

[trapperjohn]

SilverSaloon on here runs two 124 24v Estates on WVO. This thread may give you an insight to what you may need. Look up his other threads too. Note this thread is from 2010.

http://www.mbclub.co.uk/forums/ot-off-topic-forums/100297-w124-finally-rescued.html

 

[wastedisposal]

Thank you trapperjohn, I've come across SilverSaloon recently on another forum, vegetableoildiesel. He is a very helpful chap.

 

[trapperjohn]

He certainly knows his stuff about the veggie burners.

The system is not for me but each to their own and Good Luck in your pursuit of cheaper motoring.

 

[wastedisposal]

Finally the 22mm Allen key have arrived this morning. So I've managed to remove the fuel strainer. To my disappointment it was completely clear. I am quite puzzled where the fuel blockage is located. I will fill the tank with diesel and try to start it tomorrow. So far I've change the fuel filter and pre filter and the clear fuel lines. Is there anything else I should do?

 

[wastedisposal]

This morning I have filed the car with diesel and the fuel filter. Removed the glow plug relay, which is located on the passenger side of the engine bay, inside a black fuse box. Tried to crank the engine but unfortunately the battery was flat. I could see diesel in the clear fuel lines. My other car, 1.6 Civic, could not generate enough power to start the old beast. So I had to make a trip to Halfords and purchase a battery charger for £29.99

 

[bolide]

To start one of these with air in the lines, charge the battery completely & refit it. Then hook it up with BIG jump leads to a car with a big battery, fire that up and let it idle. Then try the 300 Diesel.

Once the 300D starts to kick, cycle the glow plugs three or four times and try again with your foot on the floor

Nick Froome

 

[wastedisposal]

Finally this morning I've managed to start it. With a fully charged battery and after few attempts the engine started. I was so relieved; my lovely car has been off road for over three weeks now! Unfortunately the engine has now developed a new fuel leak. I left the engine running for 30 minutes and when I returned, I’ve noticed a big wet stain underneath the engine bay. As far I can tell diesel fuel is dripping from the manifold. The fuel filters and clear fuel linen seems to be dry. I am wondering where else it might be coming from. There is a possibility that I have connected the clear fuel line incorrectly. I can see a lot of air trapped in there.

 

[SilverSaloon]

hi

things to check;

- black rubber pipes that connect to the metal lines that run under the car on both the tank side and the engine end can go brittle/crack and let air in, especially with thick veg
- v cold at the moment - not the best time to be starting on WVO
- the fuel heater can let in air. take it off, add some "instant gasket" to help it seal nice and tight
- take a look at what clear pipe shows bubbles 1st - the connection(s) before this will be at fault.
- Guttman fuel filters from Eurocarparts are my prefferred filter. nonsense about the mann truck filter, the standard filter will be fine.
- check for wetness around the delivery valve seals as these will probably need doing at some point and their condition depends on how quickly the veg finishes them off
- it takes a few miles for bubbles to dissapear when air has got into the system
- are you adding petrol to the WVO to think it? too much and this can vaporise creating bubbles too. 10% max is a good value to keep to.

 

[wastedisposal]

It is good to hear from you SilverSaloon. I am aware the weather is a problem. At present the car is running on 100% diesel. I will check the air bubbles and the fuel heater. Delivery valve seals are on my check list. As recommended I bought the fuel filters from Eurocarparts. Previously I've added 5 litres of unleaded to 70 litres of WVO.

 

[SilverSaloon]

Previously I've added 5 litres of unleaded to 70 litres of WVO.

yeah i tend to keep to approx 10%, which is rough - i either add about 1 litre to every 20 litres from jerry cans as i fill it or if they are empty i fill the car from empty and put 7 litres of petrol in at the tax station along with filling the jerry cans.

Seen your post after another W124 running on veg. if this is to replace the above car which you have problems with then its not worth it - any veg car will encounter these sorts of problems everyso often whether its currently running on veg or not. I'd just stick with it and sort the car you have out. It will be a very simple and cheap issue but just hard to pinpoint. Once you've done all that you'll have good knowlege of the fuel system and willl be able to sort any future issues out really quickly.