Jaylee's tech tip of the week!

[jaylee]

As you all probably know, i'm not very technically minded with mechanics...
Electrical gadgetry i'll have a go, but engines i tend to steer clear & leave for the experts...!

My question was to do with this little fellow that sits with his mate... & this was what i found out.
Its a valve solenoid that lifts the revs on idle when the air con is on, & by all accounts the one on the right with the white connector block has a tendency to fail...
Now, i'm assuming they both are controlled by the ECU? Along with the relevant fans..
But don't be fooled into thinking it's just for the revs during AC running.. Oh, no it helps the other one with the revs on the cold start till warm up too!! (Help me out someone in the know?)



Anyway, my point is this.. (& Many thanks to Kirsty & Dandywarhol for taking the time & helping me get my head round this, on this thread http://www.igmaynard.co.uk/bongo/forum/ ... 04&start=0 & another thread which i fail to find! )

Back to my point... If or when you look for a replacement (& apparently this fault is quite common on these solenoids.) If you go for a used unit..? (They are £70 new. ) It seems to be the one with the white block with the white dot that dies??
I was lucky & managed to get the two for gratis!! Thanks Bell hill for posting em to me, i got em this morning! & i got it installed & working... (Though the white dotted one they sent buzzed a little & with a meter test looked like it was on its way out.

The tip?!!

DON'T get the one with the white dot on it!


As Wesley Snipes in the film Passenger 57 said.. "Always bet on black"!!

[helen&tony]

Hi Jay
Nice clean engine....do you want a job???
Cheers
Helen

[missfixit70]

If you've blanked off your egr, you can also use one of those Still haven't sussed the full operation of these, got enough other things to figure main thing is it works (I think)
If I switch the ac on when the engine's warmed up (hour driving) & ticking over, the revs jump up a bit, BUT, if I switch the ac off the revs jump up again to @1000rpm, rather than dropping back down, wierd

[jaylee]

All i know is they both hold the revs up on the cold start, but the one on the right (or should i say the circuit with the white block) holds the revs for longer & lifts the rev to compensate for the drop when the AC is on. There is a 1/2 second delay then you feel it click. There is also a constant 12V coming off the white wire when the engine runs.. When activated the voltage switches off, that's when it routs the vacuum to pull back the thing on part 24-8002 http://www.lushprojects.com/bongopartsmk2/1R29921.gif

You could adjust the screw on 24-173A if it doesn't compensate exactly i suppose..?
Mine seemed pretty spot on!
Even prior to fitting this part the revs on idle never dropped to the point the engine was struggling.. But there was a slight dip.
Now it seem to be kept more constant... But it still begs the question, why did they fit two of these things? Why not just the one?

I mean they both are inline with the vacuum hose which you can just make out running up from underneath the spark plug stuff just under the double solenoid bracket.

If you've blanked off your egr, you can also use one of those Still haven't sussed the full operation of these, got enough other things to figure main thing is it works (I think)
If I switch the ac on when the engine's warmed up (hour driving) & ticking over, the revs jump up a bit, BUT, if I switch the ac off the revs jump up again to @1000rpm, rather than dropping back down, wierd

Kirsty are you saying it jumps to 1000 before settling back to 750?

Don't ask me about the egr.. I only just got my head round this!

[missfixit70]

It had been at @750 to start with, turn on ac, jumped about 100 rpm to 850 rpm, then when ac turned off again, jumps to just under 1000rpm & stays there (for at least 5 minutes, got bored waiting) rather than dropping back to 750rpm. I may investigate further at some point in the future when the round tuit list diminishes & I have the conversion finished, probably some time around 2012 at present rate of progress

[jaylee]

I have just found out with Dandywarhol's pedal tip! That when the solenoid is activated it's accompanied by the fans... It cuts in & out during the use of the AC.. (i suppose depending on engine temp.) & it activates with the other one (as said earlier.) when cold starting but no fan. my tick over a constant 750 & She starts on the button.

Sorry i wouldn't make much of a Scientist.. I'm kind of doing this while i'm doing the house work.!

[Rhinoman]

Given that they are just Vacuum Solenoid Valves and I wouldn't imagine that there is much difference between them I would guess that the real issue is that the one with the white dot is mounted where its hotter or where there is more vibration.

[helen&tony]

Hi
Aha...another job i've been meaning to sort...now that air-con weather is here...when my aircon cuts in on tickover, the revs drop, so...which one is the solenoid valve I want, and as I blanked off the EGR ages ago, where's that one, so I can swap it
Cheers
Helen

[jaylee]

Given that they are just Vacuum Solenoid Valves and I wouldn't imagine that there is much difference between them I would guess that the real issue is that the one with the white dot is mounted where its hotter or where there is more vibration.

I was thinking along similar lines Rhinoman.. It seems to work along the principle of a remote locking actuator, but instead of reverse polarity more like how a relay works?!

I think it's more like 15 years of wear & tare.. I does on the face of it appear to do more work than the solenoid sat next to it..

Hi
Aha...another job i've been meaning to sort...now that air-con weather is here...when my aircon cuts in on tickover, the revs drop, so...which one is the solenoid valve I want, and as I blanked off the EGR ages ago, where's that one, so I can swap it
Cheers
Helen

Helen, I'm hoping Kirsty will put me right on this one...
(Don't quote me on this.)
I think it's the one with (Well, mine has) a red dot to the left of the two solenoids i've been on about..?

Left of the center, that bundle of loom & hose..?

[helen&tony]

Hi Jay
Ta...that'll be the horizontal one then?....i think I'll go and lift the seat and look at mine to see if that makes it better ...That'll be a job for the week after next...So many things to do...a number of Bongo related...PLUS repairs in the garden seating
Cheers
Helen

[missfixit70]

There's 2 at the rear that are associated with the egr, the electrical connectors are different, but I just made up two little m-f connector cables so it just plugged in in place of the one that doesn't work. Be very gentle though, they are very brittle.

[helen&tony]

Hi Kirsty
Which is the one for the aircon?...I didn't like pulling plugs, for just that reason...old plastic....four of the little beggars!...
The one for the EGR....is that right at the very rear?...and can it be removed...on lushprojecte there seems to be one with 3 vac. hose connections instead of 2?...is that the one?
Cheers
Helen

[missfixit70]

Both the rear 2 are for the egr.

[helen&tony]

Hi Kirsty
Thanks...I'll see what I can do with them
cheers
Helen