Injector pump moise, 300tdi, LR90

Are you sure it's not compression escaping from a blown head gasket?

On or around Mon, 03 Dec 2007 17:55:19 +1300, EMB enlightened us thusly:

the bosch pump on the TDi seems generally to be reliable, and not to need attention. AIUI, transesterification is exactly what you do to the oil so it DOESN'T gunge up the pump.

Worth a check indeed! I just wondered if it was connected with my recent use of TE'd veg oil.

Cheers

Neil

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Update....

Sadly, it is the injector pump :o(

Whether this is directly a result of my use of vegie diesel is unlikely to be certain. But it's damned coincidental if it isn't!

Ho hum Neil

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How long have you used veggie? I ran straight veg, 100%, for something like 3 months or so covering perhaps 7,000--8,000 miles, that was 40,000 miles ago and the engine's never missed a beat. That's in a Defender 300TDi, 1994 vintage (a good year, plenty of body and a nice red colour, exceptional aroma).

Hmm, might have been more like 2,000--3,000 miles now I think about it.

"since July this year, I've been running a mix of transesterified veg oil at between 40 and 60% mixed with DERV? Or was the pump on it's way out anyway? I've had the vehicle since 2000 and had no fuel related problems so far."

In terms of miles it probably less than 1500, I'll check later.

The blend is slightly thicker than DERV, a dark green colour, strong distinctive aroma(almost sickly), but the usual smell from exhaust.

Anyway, the injector pump is slightly buggered, but the odd thing is the diesel engineer doing the repair says he thinks the mix is too THIN - I'm puzzled to say the least! Further investigation is called for here.

Neil

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Update 2

I checked the mileage since I first started using this fuel, and it's just a few miles over 1000.

There are several damaged parts inside the pump which the diesel specialist is fairly certain is attributable to lack of lubricity in the fuel. Both he and my service guy were puzzled by the thinness of what was present in the pump and the fuel filter, and also puzzled by the smell of it. So I made enquiries and learned that mix is RME(?? methyl ester) blended with Dipentene to obtain the correct viscosity.

Coincidentally, a Bosch engineer was around while my pump was being repaired. He had a look at the damage and said he had seen this before recently with people using various oils as diesel fuel, without there being sufficient lubricity and cushioning effect of the internals of the pump.

My service guy is interested in seeing the stuff I've been using in it's raw state, so he's getting a sample when I pick up the motor.

Incidentally, my service guy had correctly diagnosed the cause of the loud clicking coming from the pump - it was one of the internal valves

I hope this is of use to others here.

Neil

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