Back Plate

[wohlmeyer]

Hi all,
 

I have decided to powder coat my cam covers, secondary injector manifold, and plenem chamber.  I also want to powder coat the back plate that the throttle bodies screw into.  It doesnt look like a big deal to take off the back plate (8 screws?)  Lotus warns not to disturb the back plate or the throttle linkage but I have no idea why it would be a big deal to take off the back plate as along as I replace the gaskets....?   

 

 

Any comments, advice, or personal painting stories would be appreciated.

 

Thanks

 

Bill

[dodge1979]

No problem in removing the back plate of the plenum, there is an individual gasket between it and each throttle. Just make sure you use wellseal on all the gaskets for the throttles to backplate, the plenum cover to backplate and the plenum nozzle to plenum chamber. This will ensure a perfect long lasting seal.

[Vulcan Grey]

Have a look at my engine rebuild photos in my link in my sig below. I painted mine. Main issue was that the idle bypass hose was hard as a rock and shattered when I removed it... that hose is over $120...

Take a photo of the throttle adjuster in case it comes apart, so yo can put it back together correctly!

[wohlmeyer]

Thanks for the replies.  I didn't think there was any serious issue with removing it.  Im also replacing my turbo with one of Marcus' turbos.  When I pulled the turbo to chargecooler hose off, the inside of the hose was coated in oil...

[Vulcan Grey]

that's fairly normal for the Esprit, since the crank-case breather vents into the air intake before the turbo.  If there is too much oil in there, then you should do a compression test on the cylinders.

 

Or you can install an oil catch can to keep the oil out of the intake, but it'll have to be sized correctly for a boosted engine, or it'll blow the dipstick out.  It is best to do a good air/oil separator and pipe that back into the intake, so you get the benefit of the suction of the turbo to depressurize the crank (more power, better economy).

[wohlmeyer]

Is there an easy way to seperate that back plate from the throttle bodies?  I do not see any way to reach the screws on the underside without pulling the entire throttle body fuel rail apparatus out of the car... I would  rather not do that I hope there is an easier way to reach those screws...or is that the proceedure?  To pull the entire fuel intake out of the car throttle bodies and all?

Edited May 19, 2014 by wohlmeyer

[Vulcan Grey]

It's these 8 bolts through the throttle bodies and the fragile bypass hose....  difficult to do in the car!

 

This hose will almost certainly break, like it did on my 89SE.  An new one was $120 so I made one from some Aeroquip hose that bends in a tight radius ($9/ft 10 ft min...)

 

 

[wohlmeyer]

It's impossible to do with the intake in the car.  Im crying uncle on this one and im going to try and paint it while it is in the car.  I just dont have access to the lower center screws with it in the car.  Ugh.

[Vulcan Grey]

Forgot to say.  NEVER lean on the intake manifold! Some people have cracked theirs, especially when the support bar to the block is loose or off.

[wohlmeyer]

got it...

 

Edited May 23, 2014 by Vulcan Grey

[wohlmeyer]

So here is my delima now.  In the process of getting the backplate off, I accidently broke the seal between the throttle bodies and the intake manifold.  I didnt damage the gaskets at all, the throttle bodies separated from the intake when I pulled the backplate off.  I have new gaskets for the backplate should i replace the gaskets throttle body to intake?  Or leave it alone.

[Vulcan Grey]

new gaskets! an air leak in the intake will cause drivability issues.

 

Just make sure they aren't a poor fit and get in the flow.