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Hi all

Has anyone ever changed their vacuum pump with engine still in car?


Have diagnosed, my pump is only making negative 20psi, not enough!

Any info would rock!
 

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Hi all

Has anyone ever changed their vacuum pump with engine still in car?


Have diagnosed, my pump is only making negative 20psi, not enough!

Any info would rock!
It certainly can be changed in situ. There are some guides in the how to's on changing the timing chain, you pretty much have to do all those steps to get the pump on and replaced.

No idea if 20psi is enough, worth double checking as it is a big job.
 

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It certainly can be changed in situ. There are some guides in the how to's on changing the timing chain, you pretty much have to do all those steps to get the pump on and replaced.

No idea if 20psi is enough, worth double checking as it is a big job.

I've just bought this Navara D40 a few weeks ago, it was not running - I installed the duplex timing chain kit and just prayed for the best.

It was running fine when started, but it had no vacuum. I'm running a hose off the back of the vacuum pump to the boost control solenoid as it just has enough vacuum to keep the wastegate closed to make boost and make the car run fine, but the pump is not man enough to control the brake booster. Lucky I don't have far to drive to and from work as it is a little difficult to pull up this car without assisted brakes.

I have found a replacement pump for $150AUD, being delivered tomorrow. I plan on replacing the vacuum pump over the weekend and hoping for the best and restored vacuum to my turbo & brakes!

Looking through this forum and just on google images its hard to see how it bolts in, I just hope that I do not have to remove the fuel pump!

As stated before, I tested the pump, its slow to react and only goes down to -20PSI, I've been told its not enough, should be around -25/-28psi, I believe volume is also an issue with my current pump

Will post results!

Regards,
XCL08
 

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This problem has fixed itself !

So a little about the D40 so I can try and get my head around it also.

It was sitting in a shed for 8 to 12 months. I've bought it on a gamble that it would work. I read around and found out that the YD25 engine is good at breaking timing chains. So in order for this not to happen I replaced the timing chain, did a EGR delete while I was there and a hoy I cranked the engine and away she went.

I had an issue of stuff all vacuum this whole time, only had enough to shut the wastegate so it made power. I've done around 100kms and I thought I'd check the vacuum again this afternoon, plumbed the brake booster back in along with the wastegate and hey presto its all working again!

Could it be possible that the veins in the pump were stuck and this was the reason it was not making good enough vacuum in the beginning?

weird, but wonderful that it is now working!

Happy Dance.

Regards,
XCL08
 

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Good that it sorted itself out, I reckon your theory about sticky vanes was sound, this is not a very nice job to have to undertake.
However if another owner should have a similar problem and read this thread, they will get misled into believing their vacuum pump has indeed failed.
The figures you have tested to, and specified are incorrect.
Atmospheric pressure is approximately 1 bar or 14.7psi (give or take a little, dependent on where in the world measured, and prevailing weather conditions), therefore an absolute vacuum (the highest achievable) can only ever be approximately (for the reasons given above) 14.7psi.
The specification you were given of -25/28psi is approaching DOUBLE absolute vacuum, this can never be achieved.
Is there a possibility you were told these figures in psi, when the actual measurements should have been quoted in 'inches of mercury'?
 

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How would you clean the vanes in the pump ... or is it just luck?


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It is possible that, given the engine was static for a long period time of time, the vanes at the top would fall into their grooves on the centre hub, 'stiction' developing over time would then hold them in place until, heat, fresh oil and centrifugal forces could then break their hold, and fling them outwards to resume sealing against the cylinder walls, the pump would then work again as designed, this would also account for the lack of capacity the OP reported.
Generally speaking vacuum pumps are one of the more reliable, long lived components.
 

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Took my boost solenoid off today and cleaned it, out back on and drove 5 mile as it was before then all of a sudden lost all boost. All pipes as still attached and in correct places as before.

I also tried as landmann said and took the vacuum pipe off and onto the actuator to see if the lever would move at idle but didn’t.
So would you reckon my pump is dead?
going to try my wifi device and dashboard see if any level of boost at tall.


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Boost is back, I'm not sure if it went into limp mode... But there was no turbo but enough power to move unlike the limp mode I've had before.


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Mine is doing the same, going into limp mode and no engine fault

Going to replace the SCV this week and see if that fixes my problem as stated before this Navara has sat for quite a few months and the SCV could be sticky
 

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Hi all

Has anyone ever changed their vacuum pump with engine still in car?


Have diagnosed, my pump is only making negative 20psi, not enough!

Any info would rock!
Hi, did You change the pump? And was it doable without removing the whole engine?
 

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I've just bought this Navara D40 a few weeks ago, it was not running - I installed the duplex timing chain kit and just prayed for the best.

It was running fine when started, but it had no vacuum. I'm running a hose off the back of the vacuum pump to the boost control solenoid as it just has enough vacuum to keep the wastegate closed to make boost and make the car run fine, but the pump is not man enough to control the brake booster. Lucky I don't have far to drive to and from work as it is a little difficult to pull up this car without assisted brakes.

I have found a replacement pump for $150AUD, being delivered tomorrow. I plan on replacing the vacuum pump over the weekend and hoping for the best and restored vacuum to my turbo & brakes!

Looking through this forum and just on google images its hard to see how it bolts in, I just hope that I do not have to remove the fuel pump!

As stated before, I tested the pump, its slow to react and only goes down to -20PSI, I've been told its not enough, should be around -25/-28psi, I believe volume is also an issue with my current pump

Will post results!

Regards,
XCL08
Hi
Just wondering where did you get your replacement vacuum brake from ?

Thanks
Brad
 
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