Biodiesel and rubber seals

[Dr Mark Senior Member Find all posts View Profile Close Dr Mark]

I am getting back into bioifuels after a hiatus of several years. I'm, going to run my Merc on bio, as their fuel pumps are all metal, so they are bulletproof, but I have to decide whether to run my Pajero on bio or WVO.

Conventional wisdom has it that bio attacks the rubber in IPs so they need to be rebuilt with Viton as a one off cost. But occasionally I hear whispers from people who say that they've run bio with their standard rubber seals for years with no problems. So my question is this - how many people out there have had this experience? Are you running a car on bio with your standard seals? If so, what type of car is it?

This question is sparked by the fact that there are different types of rubber - it's entirely possible that some types of rubber are bio-compatible and others aren't

cheers

[tillyfromparadise Senior Member Find all posts View Profile Close tillyfromparadise]

Re: Biodiesel and rubber seals

Indeed, some types of rubber are biodiesel compatible and others are not.
I ran my Gemini on biodiesel for over three years without any seal or hose problems. This included the 25 year old fuel lines

[Matt Senior Member Find all posts View Profile Close Matt]

Re: Biodiesel and rubber seals

There are rubber seals and then there are rubber seals, in general they will give up at the most inconvenient time. Seals go sooner rather than later these days on ULSD so be prepared for a rebuild, its inevitable. I saw you mobile number on my phonr yesterday and thought of you when we caught up. Good to see you back.

[Dr Mark Senior Member Find all posts View Profile Close Dr Mark]

Re: Biodiesel and rubber seals

Thanks guys. I guess I'll just try the bio and see how it goes. All you need is one person to have successfully run it with standard seals to make it worth a shot.

The IP in my landcruiser only lasted a couple of months on bio, but I'm not convinced that wasn't just a coincidence, as when it was dismantled there was sign of mechanical wear on some of the components

[Johnnojack Senior Member Find all posts View Profile Close Johnnojack]

Re: Biodiesel and rubber seals

The Paj. IP (VE type) is all metal too. There are some seals of course, only three have moving shafts, the fuel control shaft (throttle) turbo compensator rod and the front seal. All the others are O rings, except the top cover seal, and are static, so will last a long time if not disturbed. In any case, with the possible exception of the top cover seal, all can be replaced with Viton seals which can withstand biodiesel.

[83Patrol Donating Member Find all posts View Profile Close 83Patrol]

Re: Biodiesel and rubber seals

What year model Pajero is it?

[Dr Mark Senior Member Find all posts View Profile Close Dr Mark]

Re: Biodiesel and rubber seals

What year model Pajero is it?

1988. Series 1 I think - very square looking. 2.5 intercooled TD

[geewizztoo Senior Member Find all posts View Profile Close geewizztoo]

Re: Biodiesel and rubber seals

I'm assuming this has the 4D56 engine, which is the same one used in the Triton. My son ran his Triton ute on bio for more than three years without any problems.