Author Topic: Different Pump part number requiring more advance?  (Read 2171 times)

July 28, 2016, 10:48:34 am

BananaDiesel

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Different Pump part number requiring more advance?
« on: July 28, 2016, 10:48:34 am »
I am just setting my timing after a rebuild and noticing that my pump seems to require a lot of advance to start nicely. Originally had it set at 1.05mm and could not start at all. With the cold start pulled it did eventually start and ran quite well.

When I did get it started using the cold start lever and then pushing the lever back off (engine still cold air temp at 25C 72F) it idled horrendously with timing at 1.05mm. Seems like the pump will need advance somewhere in the 1.15-1.2mm range for decent starting. I also noticed the cold start lever advances time around .20mm which seems a bit high.

I don't know to much about the history of the pump; It was purchased off a shop who had it rebuilt using Viton seals, put it in a new build, and then pulled the engine when the car was wrecked after a 1000km or so. Pump ran quite good on a tired engine but always had pretty bad cold starting. The part number on the LDA cover is 1 465 530 724 which is not a standard part number. The pump is 0 460 494 182. I assume the LDA cover should not effect operation in any way? Can some pumps just require significantly more advance?

Compression seems fine. Car runs and pulls hard when timing is advanced. Glow plugs are new and pulling full current, and there is a 4psi primer pump insuring there is always fuel at the injection pump. Also just to clarify the timing belt is bang on; it was set when the camshaft sprocket was reattached.

Cheers.

Reply #1July 28, 2016, 11:48:20 am

srgtlord

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Re: Different Pump part number requiring more advance?
« Reply #1 on: July 28, 2016, 11:48:20 am »
The few pumps I have played with have always been set to 1.00 . A bit more advanced is not going to hurt anything.

Reply #2July 28, 2016, 12:41:58 pm

RabbitJockey

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Re: Different Pump part number requiring more advance?
« Reply #2 on: July 28, 2016, 12:41:58 pm »
maybe there is something wrong with the pump?  the only ones i have seen which got set more advanced were yellow dot pumps from a 1.5d which are na
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Reply #3July 29, 2016, 06:10:15 am

theman53

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Re: Different Pump part number requiring more advance?
« Reply #3 on: July 29, 2016, 06:10:15 am »
Too much advance increases peak cylinder pressure and can start to destroy your precups. If you need more than 1.05mm start looking for a problem

Reply #4July 30, 2016, 10:03:33 am

libbydiesel

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Re: Different Pump part number requiring more advance?
« Reply #4 on: July 30, 2016, 10:03:33 am »
There was an early 'Yellow Dot' pump for the 1.5? that required a much higher static timing plunger lift setting.  None of them had an LDA.  What place did the seals?  If it was Hans, then odds are it was screwed up.