DIESEL PUMP SEALS LEAKING!!
Moderators: Doone, westonwarrior
DIESEL PUMP SEALS LEAKING!!
hi there,
after smelling diesel coming from my engine i decided to have a good look for the fault. i have traced it to a couple of failed o rings on the diesel pump. one i could get to and replace but the other is more difficult and havnt yet sorted. i decided to have a look on the net to see if other people had had this problem and if it could be fixed without taking the diesel pump off(which is a difficult and costly affair). to my shock ive found out that this is a very common problem. especially on vehicles pre 96 and especially on jap and korean vehicles of this age. its to do with the ultra low sulphur diesel that was introduced around 05. it eats away and basically damages the seals and o rings on these early models. the seals were not designed for this uls diesel. its looking like i may have to take my bongo into the garage and have all the seals replaced on the pump. dred to think what that will cost. just wondering if anyone knows of a diesel additive that i could put in to try and counter this problem. for those of you with similar aged bongos, keep your eye out cuz it could be just a matter of time.
look forward to hearing from anyone who might have some advice,
cheers adam
after smelling diesel coming from my engine i decided to have a good look for the fault. i have traced it to a couple of failed o rings on the diesel pump. one i could get to and replace but the other is more difficult and havnt yet sorted. i decided to have a look on the net to see if other people had had this problem and if it could be fixed without taking the diesel pump off(which is a difficult and costly affair). to my shock ive found out that this is a very common problem. especially on vehicles pre 96 and especially on jap and korean vehicles of this age. its to do with the ultra low sulphur diesel that was introduced around 05. it eats away and basically damages the seals and o rings on these early models. the seals were not designed for this uls diesel. its looking like i may have to take my bongo into the garage and have all the seals replaced on the pump. dred to think what that will cost. just wondering if anyone knows of a diesel additive that i could put in to try and counter this problem. for those of you with similar aged bongos, keep your eye out cuz it could be just a matter of time.
look forward to hearing from anyone who might have some advice,
cheers adam
Re: DIESEL PUMP SEALS LEAKING!!
There is a handy fact sheet in the members area describing how to replace the seals. It does seem to be a common thing, but then any vehicle of a bongo age needs a bit more tlc.
Dom
Dom
Beyond A to B
- mikeonb4c
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Re: DIESEL PUMP SEALS LEAKING!!
Welcome slapndash.
What an extremely interesting post - I didn't know that fact. V. annoying if so
What an extremely interesting post - I didn't know that fact. V. annoying if so

Re: DIESEL PUMP SEALS LEAKING!!
The older natral rubber seals are the problem. New seals should be made of Viton. Make sure they are, usually grey instead of black in Colour.slapndash wrote:hi there,
after smelling diesel coming from my engine i decided to have a good look for the fault. i have traced it to a couple of failed o rings on the diesel pump. one i could get to and replace but the other is more difficult and havnt yet sorted. i decided to have a look on the net to see if other people had had this problem and if it could be fixed without taking the diesel pump off(which is a difficult and costly affair). to my shock ive found out that this is a very common problem. especially on vehicles pre 96 and especially on jap and korean vehicles of this age. its to do with the ultra low sulphur diesel that was introduced around 05. it eats away and basically damages the seals and o rings on these early models. the seals were not designed for this uls diesel. its looking like i may have to take my bongo into the garage and have all the seals replaced on the pump. dred to think what that will cost. just wondering if anyone knows of a diesel additive that i could put in to try and counter this problem. for those of you with similar aged bongos, keep your eye out cuz it could be just a matter of time.
look forward to hearing from anyone who might have some advice,
cheers adam
see the fact sheets for replacing them.
Let us know how you get on.
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Re: DIESEL PUMP SEALS LEAKING!!
I'd meant to ask about that. The replacement O-rings sent to me by Lawson Diesels in Edinburgh (Dandywarhol recommended) are actually green, but as they are cosher Zexel pump ones from a UK supplier I'm hoping they are nonetheless of a suitable replacement material. I've had the o/s one done a year back. the n/s one has a v. slight dribble but - so far - not enough for me to feel action was necessary. But I have employed an interesting simple and effective dodge to avoid diesel on the road. Its a clean rag, left lying on the tray beneath the engine, where any diesel drops onto first. Works a treat - just renew rag from time to timeBiobongo wrote:The older natral rubber seals are the problem. New seals should be made of Viton. Make sure they are, usually grey instead of black in Colour.slapndash wrote:hi there,
after smelling diesel coming from my engine i decided to have a good look for the fault. i have traced it to a couple of failed o rings on the diesel pump. one i could get to and replace but the other is more difficult and havnt yet sorted. i decided to have a look on the net to see if other people had had this problem and if it could be fixed without taking the diesel pump off(which is a difficult and costly affair). to my shock ive found out that this is a very common problem. especially on vehicles pre 96 and especially on jap and korean vehicles of this age. its to do with the ultra low sulphur diesel that was introduced around 05. it eats away and basically damages the seals and o rings on these early models. the seals were not designed for this uls diesel. its looking like i may have to take my bongo into the garage and have all the seals replaced on the pump. dred to think what that will cost. just wondering if anyone knows of a diesel additive that i could put in to try and counter this problem. for those of you with similar aged bongos, keep your eye out cuz it could be just a matter of time.
look forward to hearing from anyone who might have some advice,
cheers adam
see the fact sheets for replacing them.
Let us know how you get on.

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Re: DIESEL PUMP SEALS LEAKING!!
The green ones are supposed to be low sulphur fuel and bio friendly
Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Re: DIESEL PUMP SEALS LEAKING!!
Yeh, stand corrected, Green. Just hooked out the box I keep ready for when replacement required.dandywarhol wrote:The green ones are supposed to be low sulphur fuel and bio friendly
On the Box:
BOSCH:
1 St/Pc
EP/VE/F
1 467 010 520
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Re: DIESEL PUMP SEALS LEAKING!!
Excellent 

Re: DIESEL PUMP SEALS LEAKING!!
Hi all,
thanks for letting me know about the fact sheet. thats just what i need. il let you know how i get on.
cheers again adam
thanks for letting me know about the fact sheet. thats just what i need. il let you know how i get on.
cheers again adam
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Re: DIESEL PUMP SEALS LEAKING!!
To infinity and beyond
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Re: DIESEL PUMP SEALS LEAKING!!
Holy CowThe Great Pretender wrote:You may find this interesting.![]()
http://www.vwdieselparts.com/forum/view ... +stripdown

Interesting isn't the word!
Intricate isn't an adequate word either

Nor is Involved

Ingenious belongs in there somewhere

Intgenvolvtriceresting oughta cover it

....boy we could use something as good as this for the Bongo fuel pump, plus how to get the damn thing back on and timed correctly.
Or then again just stump up £600 and have a reconditioned one fitted

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Re: DIESEL PUMP SEALS LEAKING!!
I don't think the LARGE HADRON COLIDER is as complicated as that.
Last edited by daveblueozzie on Fri Dec 04, 2009 12:12 am, edited 1 time in total.
Lost without my Bongo.
Re: DIESEL PUMP SEALS LEAKING!!
daveblueozzie wrote:I dont think the LARGE HADRON COLIDER is as complicatede as that.
No, but that don't work either.

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Re: DIESEL PUMP SEALS LEAKING!!
Thats a good link TGP
These old pumps are capable of producing pressures of over 150 BAR (the average car tyre pressure is 2 BAR!) Modern diesel HDI etc. are producing nearly 2,000 BAR
purely by better tooling creating ultra tight clearance tolerances - thats why they don't like heavy, viscous veg oil........................


Whale oil beef hooked
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Renault Lunar Telstar
Yamaha TD1C 250, Merc SLK200, KTM Duke 690
Re: DIESEL PUMP SEALS LEAKING!!
Plus, I believe, VO go's solid, as in makes plastic, under those pressures within the common rail.dandywarhol wrote:Thats a good link TGPThese old pumps are capable of producing pressures of over 150 BAR (the average car tyre pressure is 2 BAR!) Modern diesel HDI etc. are producing nearly 2,000 BAR
purely by better tooling creating ultra tight clearance tolerances - thats why they don't like heavy, viscous veg oil........................