Fluctuating Idle RPM -Diesel P38

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Wazzajnr said:
Would it be possible that the bright links on the chain are one link out?
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This has already been mentioned as a possibility and dismissed by the OP. However in his photo all looked reasonable reference sprocket position and pump position. The timing marks MUST be 12 raised links apart so bright links are not really needed. If engine is locked at TDC and any raised link is placed against the crank mark the twelfth raised link to the right including the one on the crank mark goes against the # 6 marked tooth on pump sprocket. That then places the key way uppermost at about five past the hour. The pump is then set with the key uppermost to making next injection number one and turned on it's slot until sprocket can be engaged. It really is as simple as that. If all that has been done properly and the OP cannot get more than .71 mm lift on DTI with pump fully towards engine and at the end of it's adjustment slot. Either the chain is set wrong with timing marks too many links apart, which from his photo that does not seem to be, or the thrust washer is missing from the pump piston. It cannot be anything else.
 
wammers said:
This has already been mentioned as a possibility and dismissed by the OP. However in his photo all looked reasonable reference sprocket position and pump position. The timing marks MUST be 12 raised links apart so bright links are not really needed. If engine is locked at TDC and any raised link is placed against the crank mark the twelfth raised link to the right including the one on the crank mark goes against the # 6 marked tooth on pump sprocket. That then places the key way uppermost at about five past the hour. The pump is then set with the key uppermost to making next injection number one and turned on it's slot until sprocket can be engaged. It really is as simple as that. If all that has been done properly and the OP cannot get more than .71 mm lift on DTI with pump fully towards engine and at the end of it's adjustment slot. Either the chain is set wrong with timing marks too many links apart, which from his photo that does not seem to be, or the thrust washer is missing from the pump piston. It cannot be anything else.
Click to expand...

Is it possible the chain has the wrong number of links?!
 
Wazzajnr said:
If it's Chinese, anything is possible. I make good money putting Chinese machines right, they can't make 2 things the same!
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No Chinese crap. Chains & other parts, bought from Rimmers of UK, genuine parts.

If by chance the pump shaft washer dropped then would not I face with the hot start problem at this level from that point of time?
As I mentioned, the car started after few turns when hot & at that time the in tank pump too was not in good health. The hot start issue became very serious after mid 2016 or so.
 
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kapilamuni said:
No Chinese crap. Chains & other parts, bought from Rimmers of UK, genuine parts.

If by chance the pump shaft washer dropped then would not I face with the hot start problem at this level from that point of time?
As I mentioned, the car started after few turns when hot & at that time the in tank pump too was not in good health. The hot start issue became very serious after mid 2016 or so.
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Now listen carefully i will say this only once. IF with engine locked solid at number one firing, with chain set with twelve raised links between timing marks on crank and pump sprocket. And with woodruff key on pump placed vertically and pump engaged in pump sprocket, you can only get .71 mm lift on cam with pump fully turned towards engine at the end of it's adjusting slot. Either the cross drive in the pump is flopping about like a whippets dick or the thrust washer has dropped out. There cannot be any other explanation. The high modulation is clearly being caused by a mechanical problem rather than an electrical one. Maybe time for that new pump you were thinking about. But for pity sake get someone who knows what they are doing to fit it for you.
 
That option is expensive & will be the last resort.
To verify its there, I will have to remove the pump mid section n see.
This is going to be messy.:mad::mad::mad::mad::mad::mad::mad::mad::mad:
 
As one of the founding members of misplaced humour may I just take you backstage and reveal Wamms in a light summery dress accidentally on purpose falling into a freezer in Lidl's in an attempt to stock up on pop ices.
For reference well into the future I suggest to any reader to refer to uk temperature stats, pmsl.

Ps. Hey Wamms, pop into Boots for those legs ya monkey, and consider a holiday to Brazil!!
 
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If the thrust washer has dropped out , I guess, getting a lift of 0.95mm is impossible anywhere within the range of pump body rotation. But, I got 0.95mm lift somewhere , more towards the retard range (pump pushed away from the engine) . However, that position is too retarded with a whitish smoke & rough running.
 
kapilamuni said:
If the thrust washer has dropped out , I guess, getting a lift of 0.95mm is impossible anywhere within the range of pump body rotation. But, I got 0.95mm lift somewhere , more towards the retard range (pump pushed away from the engine) . However, that position is too retarded with a whitish smoke & rough running.
Click to expand...

No it is entirely possible. But not if the slot won't allow the pump to rotate far enough up the cam on the stator plate and push the piston far enough to achieve it. Which would happen IF with engine locked solid at TDC the chain had been fitted incorrectly the timing marks were too far apart and the pump sprocket was in the wrong place, positioning the key way towards the engine. Or the thrust washer had fallen out giving essentially a slightly shorter piston. When initial static is set with engine locked at TDC, chain in correct position on timing marks, injection pump piston cam at low null point of cam on stator plate. There should be a bias of available pump movement towards engine to allow for static setting and to also allow for further movement towards engine to take up chain stretch. You obviously do not have this situation. You have done something wrong, the only thing you can now do is revisit what you have done and correct it. From the questions you ask you really don't understand what you are doing. Find someone near you that does.
 
wammers said:
No it is entirely possible. But not if the slot won't allow the pump to rotate far enough up the cam on the stator plate and push the piston far enough to achieve it. Which would happen IF with engine locked solid at TDC the chain had been fitted incorrectly the timing marks were too far apart and the pump sprocket was in the wrong place, positioning the key way towards the engine. Or the thrust washer had fallen out giving essentially a slightly shorter piston. When initial static is set with engine locked at TDC, chain in correct position on timing marks, injection pump piston cam at low null point of cam on stator plate. There should be a bias of available pump movement towards engine to allow for static setting and to also allow for further movement towards engine to take up chain stretch. You obviously do not have this situation. You have done something wrong, the only thing you can now do is revisit what you have done and correct it. From the questions you ask you really don't understand what you are doing. Find someone near you that does.
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I don't think there is anyone near him who is competent. That's why he is trying himself. He's in Sri Lanka, isn't he?
 
Check maximum DTI reading when rotating engine by hand - it should read something over 2mm at the highest point.
 
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