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Jussi

Flap valve actuator

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Can we take the flap valve actuator away? And what it really do anyway?? ;)

There is vacuum pipe from it, this pipe is going nowhere in my car! And we tested that if you suck from this pipe it will close the flap in air pipe. When we took the whole pipe away this flap was half closed, that will affect flow.

Here are some photos that you know what I'm talking about. We have removed the air pump from the car and now we are considering to get rid of this flap valve actuator but is it safe???

Here you can see that short vacuum pipe, which is going nowhere.

valve1.jpg

valve2.jpg

Here you can see the flap in the pipe, now it's open (we opened it).

Edited by Jussi

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Just look photos of your car Jimmybondi.

In your car there isn't this flap valve actuator-thing. So it's got to be involved with emission stuff, cause USA-models only have this ;)

...hmm. wait Wayne is on the forum...soon we know all about this ;)

Edited by Jussi

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Jussi ,the flap valve actuator is to stop heat from the turbo from travelling up to the carbs when the engine has been shut off (making it difficult to restart in extreem hot conditions like Arizona) I just took the butterfly out of the valve and left the rest. If you take the lot off you will have to get the spindle hole welded up(or risk just filling it with JB Weld (liquid metal) ;) Mind you with the heatwave you are having in Finland you might want to leave it on ;)

Edited by WayneB

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As you European Esprit owners can see the inlet tract on the Federal cars is quite different (no fins, Turbo written the other way round and the flap valve) ;) Shame they didnt put a Charge Cooler in there ;)

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As you European Esprit owners can see the inlet tract on the Federal cars is quite different (no fins,  Turbo written the other way round and the flap valve) ;)  Shame they didnt put a Charge Cooler in there ;)

<{POST_SNAPBACK}>

Question:

If it's so damn hot in Arizona, why have they deleted the fins?? ;)

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Jimmi, Dont need the fins because we have a large ducted Electric fan in the engine cover to suck the heat out ( thermostatically controlled) I have mine on a swich also (poor mans Charge Cooler) ;)

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Just in curious what this small vacuum pipe do and where it was connected?? Or is it a vacuum pipe at all?

<{POST_SNAPBACK}>

Yes it was connected to a vacuum source to open the valve when the water temp goes over 90 degrees C (boost pressure blows it open anyway) ;)

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Flap valve actuator is now history on my car ;)

We filled the screwholes with liquid metal just like you advised Wayne B)

Engine area seems now a lot clearer when we got rid of those emission stuff. Project continues tomorrow B) we will see if it starts anymore ;)

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Jimmi, Dont need the  fins ...

<{POST_SNAPBACK}>

Would you dare to repeat that face to face with Jussi or Kimi R. ;)

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There is a expression (older people might know this).

Take a Finn if you want to win ;) It's from time when finnish always won the rally championships (names like Ari Vatanen, Hannu Mikkola and so on).

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There is a hose from plenum chamber can we take it away? (and plugged the hole)

Here is a picture, hose leaves from the right side (where the turbo-text is).

case.jpg

This hose goes to plenum valve according to sticker on the hood.

So project continues and now we have problems again ;)

We check the timing and it wasn't right. We had to take the timing belt away. And now we couldn't put it back ;) In my car (like all USA models I think) there is an automatic belt tension pulley. We tried to adjust it but we couldn't find the 4mm. locking pin it should have ;) Tomorrow we have to take the whole belt tension pulley away to check it. This pin might be broken...and if it is what then?

Car actually started today but running was bad because of timing. Timing was wrong many tooths and sparking leads were connected wrongly to distributor. I wonder who was making last service for the car :o Now all the timing marks are like they should be but camshaft timing belt isn't where it should be ;)

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Hi Jussi

You don't need to lock the timing belt tensioner with the pin. Just back out the tension bolt 1.5 cm, if that much. That should give you enough slack in the belt to slide it over the pullies. If you feel like you need to lock the tensioner in place just use an appropriate sized drill bit.

Check the flywheel on the tranny to make sure you are at TDC along with your marks on the pullies. Make sure the pullies don't move while installing the belt.

Before you install the belt check the distributor to see if the rotor is pointing at #1 cylinder on the cap.

The distributor is spring loaded so make sure it is seated correctly by pushing in as you loosen the locking collar to adjust the timing then tighten down on the collar to keep it from popping back out.

Sorry for going of over stuff you've done and or already know. I just start writing as I remember steps in my head.

A remark on the valve actuator on the diffuser from the turbo --- the valve is there to maintain pressure in the plenum during shifts if I remember correctly. The valve opens as RPM and vacuum increase. The turbo kicks in around 3500rpm. During shifts the rpm drops along with boost pressure. The valve closes to maintain pressure in the plenum. I could be totally wrong on this one but something that I heard or read sometime ago.

louis

'83 Turbo

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The flap valve is for keeping boost in the inlet tract? Then why does the U.K./ R.O.W. not have this amazing device? Also why then have a blow off valve, boost pressure actually RISES as you shift, the throttle butterflys are closed, but ,the turbo is still spinning causing a boost spike that the blow off valve vents. The flap valve is part of the U.S. Federal spec. Emissions stuff, to stop heat traveling up the tract to the carbs when the motor is shut off, boiling the fuel and causing a crappy hot start condition. I dont know where you got the previous idea , but its a load of bollocks. ;)

Edited by WayneB

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The flap valve is part of the U.S. Federal spec. Emissions stuff, to stop heat traveling up the tract to the carbs when the motor is shut off, boiling the fuel and causing a crappy hot start condition.

<{POST_SNAPBACK}>

This makes sense, we "studied" this flap valve-thing and Wayne's explanation is very reasonable B)

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Here is a picture from this morning's work ;)

tension.jpg

No wonder we couldn't fint the pin hole, as you can see from this picture it was behind one of the bolt ;)

According to service notes this pin hole supposed to be in different place, definitely not behind the bolt. We will change new bolt with narrower heel, so in the future we will find this pin hole.

And project continues today B)

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I have the same 'bolt in the way' problem on my tensioner. Nothing is ever simple. Now just push the plunger back and hold it in place with a drill bit.

When I change the timing belt I just loosen the bolt out about 1.5 cm. It gives me just enough slack to slip the belt over the timing pulleys.

Thanks to you and Wayne for clarifying the flap valve on the diffuser.

Have a good one,

louis

'83 Turbo'

Here is a picture from this morning's work  :)

tension.jpg

No wonder we couldn't fint the pin hole, as you can see from this picture it was behind one of the bolt  :D

According to service notes this pin hole supposed to be in different place, definitely not behind the bolt. We will change new bolt with narrower heel, so in the future we will find this pin hole.

And project continues today  B)

<{POST_SNAPBACK}>

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Tensioner is now back where it should be, with new bolts and drill bit on the hole B)

Today was a "lazy" day but project continues tomorrow morning :)

And big thanks to Wayne, Louis and Jimmy :) stay in touch...there might be more questions tomorrow :D

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And more questions come.

We were thinking how easy it would be to change now the timing belt. But we can't get Lotus timing belt in a day, then I remembered that Nissan Maxima's timing belt would fit on Esprit Turbo (pre-88). Here is a link http://www.gglotus.org/ggpart/espritxref.htm

Is it true, cause we could get Nissan's belt tomorrow :D

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Jussi, Lotus changed the belt design in 1987 on the HC and HCI Esprits. I dont know weather the Maxima belt would work or not on your car. I have a NAPA no. for the belt on your car, but I dont know weather it will be of use to you in Finland. NAPA 250104. I would order the genuine Lotus belt if I were you, the valve springs on the 910 are stiff and I woulnt trust the longevity of the Nissan belt even if it happened to fit (sewing machine engine) :D

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More problems came :)

How to take the crankshaft pulley away??? It's bolt came easily out but that's it.

Car is USA-model so there are some differences. Pulley is stuck, is there somekind of special puller to take the pulley out?

What's the technique to take timing belt away with motor in place :D

We just ordered Nissan Maxima's timing belt it's exactly like Esprit's :) (cost 14euros). According to sparestores book (and importer's) Lotus use same timing belt as Maxima.

New belt arrives later today but how the h*** to change it :) I want to go drive with my car...

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